A Review of Precipitation Use Efficiency: Integrative Analysis of Ecological Connotation, Quantification Methods, and Driving Factors

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This research topic holds both theoretical and practical significance, particularly in the context of global change. It enhances our understanding of carbon-water coupling in terrestrial ecosystems and offers valuable insights for regional water resource management and ecological restoration.

The paper is well-structured, commencing with the fundamental concepts and quantitative methods of PUE. It subsequently provides a comprehensive analysis of its spatiotemporal patterns and the integrated driving mechanisms, which encompass meteorological factors, topography, vegetation-soil interactions, and human activities. Additionally, the paper examines practical strategies for improving PUE and delineates future research directions. The coverage is extensive, and the numerous literature citations include both classical and contemporary studies, demonstrating the author's substantial expertise in the field.

However, several significant deficiencies must be addressed before the manuscript can meet publication standards.

1. Language expression. Some sentences are excessively long and structurally complex, which hinders readability. Although the text is generally comprehensible, it would benefit from refinement by a native speaker to enhance clarity and flow. For instance, lengthy sentences in the Abstract (page 1) and the Introduction (page 2) could be divided to clarify the underlying logic.
2. Chinese characters. On page 8, the term "mutation characteristics" should be revised to "variation characteristics" or "variant characteristics," indicating that a previous Chinese input was not fully converted.
3. Driving factors analysis (Section 4). This section constitutes the core of the paper. Although it enumerates numerous influencing factors, certain aspects of the mechanism discussion appear fragmented and lack a cohesive, in-depth synthesis. For example, Sections 4.1.1 and 4.1.2 address temperature and precipitation independently; however, the interaction between these variables, such as the impact of temperature-rainfall synchrony or asynchrony on PUE, is inadequately explored. It is advisable to explicitly examine this interaction in Section 4.1.3 and to investigate how PUE may respond under future climate scenarios, including warming coupled with altered precipitation patterns.
4. Future Outlook (Section 6.2). The four proposed directions—interdisciplinary integration, precision remote sensing, collaborative development, and cutting-edge technologies—are all valid. However, certain descriptions, such as the "human-environment-economic" coordinated development discussed in Section 6.2.3, are somewhat general and resemble slogans. To enhance this section, it would be beneficial to present more concrete and verifiable scientific hypotheses or research frameworks. For instance, quantifying the ways in which ecological engineering measures, such as afforestation programs, improve ecosystem service values through alterations in PUE would yield clearer insights.

Author Response

1. This research topic holds both theoretical and practical significance, particularly in the context of global change. It enhances our understanding of carbon-water coupling in terrestrial ecosystems and offers valuable insights for regional water resource management and ecological restoration. The paper is well-structured, commencing with the fundamental concepts and quantitative methods of PUE. It subsequently provides a comprehensive analysis of its spatiotemporal patterns and the integrated driving mechanisms, which encompass meteorological factors, topography, vegetation-soil interactions, and human activities. Additionally, the paper examines practical strategies for improving PUE and delineates future research directions. The coverage is extensive, and the numerous literature citations include both classical and contemporary studies, demonstrating the author's substantial expertise in the field. However, several significant deficiencies must be addressed before the manuscript can meet publication standards.

Ans: We sincerely appreciate the reviewer for recognizing the theoretical and practical significance of this study, especially in the context of global change. We are grateful for your affirmation that this review improves the understanding of carbon-water coupling in terrestrial ecosystems and provides valuable insights for regional water resource management and ecological restoration. We also thank you for your positive comments on the reasonable structure of the manuscript, including the introduction of the concept and quantification methods of photosynthetic water use efficiency (PUE), the comprehensive analysis of its spatiotemporal patterns and integrated driving mechanisms (covering meteorological factors, topography, vegetation-soil interactions, and human activities), the practical strategies for improving PUE, and the proposed future research directions. We acknowledge your recognition of the extensive literature coverage involving both classic and contemporary studies, which reflects our efforts in this field. Nevertheless, we fully agree that several major deficiencies need to be addressed before the manuscript is ready for publication. We have taken your comments very seriously and made careful and thorough revisions accordingly to further improve the quality of this paper.

2. Language expression. Some sentences are excessively long and structurally complex, which hinders readability. Although the text is generally comprehensible, it would benefit from refinement by a native speaker to enhance clarity and flow. For instance, lengthy sentences in the Abstract (page 1) and the Introduction (page 2) could be divided to clarify the underlying logic.

Ans: We sincerely appreciate your valuable feedback, which is of great significance in improving the quality of our manuscript. In response to this suggestion, we have re-translated and carefully revised the entire manuscript, focusing on simplifying sentence structures and enhancing linguistic fluency. Overly long sentences, especially in the abstract and introduction sections, have been split into shorter and clearer expressions to strengthen the logical coherence and readability of the manuscript. The revised manuscript has been polished to ensure accurate, concise and natural academic English expression. We believe that the overall language quality and readability of the manuscript have been significantly improved.

3. Chinese characters. On page 8, the term "mutation characteristics" should be revised to "variation characteristics" or "variant characteristics," indicating that a previous Chinese input was not fully converted.

Ans: We appreciate your professional comments. In response to this issue, we have carefully checked and revised all professional terms in the manuscript one by one to ensure that there is no scientific ambiguity in the expression.

4. Driving factors analysis (Section 4). This section constitutes the core of the paper. Although it enumerates numerous influencing factors, certain aspects of the mechanism discussion appear fragmented and lack a cohesive, in-depth synthesis. For example, Sections 4.1.1 and 4.1.2 address temperature and precipitation independently; however, the interaction between these variables, such as the impact of temperature-rainfall synchrony or asynchrony on PUE, is inadequately explored. It is advisable to explicitly examine this interaction in Section 4.1.3 and to investigate how PUE may respond under future climate scenarios, including warming coupled with altered precipitation patterns.

Ans: We are grateful to the reviewer for the insightful and valuable comments. After careful consideration, organization and summarization, we have improved the manuscript accordingly. A new Section 5, "Comprehensive Discussion of Driving Factors", has been added to the manuscript, in which we elaborated the interactions among driving factors, as well as the response of precipitation use efficiency (PUE) to changes in water and heat conditions under future climate scenarios (Lines 558–663).

5. Future Outlook (Section 6.2). The four proposed directions—interdisciplinary integration, precision remote sensing, collaborative development, and cutting-edge technologies—are all valid. However, certain descriptions, such as the "human-environment-economic" coordinated development discussed in Section 6.2.3, are somewhat general and resemble slogans. To enhance this section, it would be beneficial to present more concrete and verifiable scientific hypotheses or research frameworks. For instance, quantifying the ways in which ecological engineering measures, such as afforestation programs, improve ecosystem service values through alterations in PUE would yield clearer insights.

Ans: We appreciate the reviewer’s careful consideration of our manuscript and the constructive comments. We fully agree with your suggestions on the "future prospects" section and have made the following revisions accordingly. We have added content related to ecosystem service value and proposed the formation of a chain transmission mechanism of "ecological engineering–ecological environment optimization–socio-economic benefits" (Lines 779-805).

Reviewer 2 Report

Comments and Suggestions for Authors

The article's theme is relevant, especially in the context of global climate change, as it links water availability to vegetation productivity and ecosystem stability. However, the article requires major revision as it presents several weaknesses, for example: conceptual and methodological.

The abstract needs improvement. The objective should be presented more directly and concisely at the beginning of the summary. The abstract does not indicate the methodological procedures of the review, for example, the databases used, the period analyzed, or the number of studies analyzed. It should also succinctly indicate the main results of the review.

The literature review needs improvement to strengthen the global perspective and critical analysis. It should be more comprehensive internationally and not focus almost exclusively on authors from countries of origin. Case studies from other regions of the world should be added. This will improve international relevance, which journals value highly.

The article does not describe the bibliographic research methodology. It does not indicate the databases used, the inclusion/exclusion criteria, the temporal scope of the review, or the number of studies reviewed. The article is not a systematic review.

The manuscript presents models but does not adequately discuss the main limitations. Table 2 lists a large number of statistical methods. However, it does not explain when each method should be used, its main advantages, and comparative limitations.

In the conclusions, the main results of the review should be presented more clearly.

The sentences are too long, complex, and sometimes there is repetition of ideas, which can make reading difficult. The sentences should be shorter and more objective, and problems such as “突变特征” need to be corrected.

Comments on the Quality of English Language

The sentences are too long, complex, and sometimes there is repetition of ideas, which can make reading difficult. The sentences should be shorter and more objective, and problems such as “突变特征” need to be corrected.

Author Response

1. The abstract needs improvement. The objective should be presented more directly and concisely at the beginning of the summary. The abstract does not indicate the methodological procedures of the review, for example, the databases used, the period analyzed, or the number of studies analyzed. It should also succinctly indicate the main results of the review.

Ans: We greatly appreciate your valuable and constructive comments. According to your suggestions, we have carefully revised the manuscript and improved the abstract accordingly. Specifically, we have presented the research objective more directly and concisely at the beginning of the abstract, clarified the methodology and workflow adopted in this review, and comprehensively summarized the core findings of this review (Lines 17-43).

2. The literature review needs improvement to strengthen the global perspective and critical analysis. It should be more comprehensive internationally and not focus almost exclusively on authors from countries of origin. Case studies from other regions of the world should be added. This will improve international relevance, which journals value highly.

Ans: We sincerely appreciate your valuable comments. We would like to provide a brief explanation here. Based on the selected literature, this review summarizes that the majority of studies on precipitation use efficiency (PUE) have been conducted in the alpine ecological regions of the Qinghai-Tibet Plateau and dryland ecosystems worldwide, and the review analysis was carried out accordingly (Lines 68-71).

3. The article does not describe the bibliographic research methodology. It does not indicate the databases used, the inclusion/exclusion criteria, the temporal scope of the review, or the number of studies reviewed. The article is not a systematic review.

Ans: We sincerely appreciate the reviewer’s careful review and valuable comments. In the revised manuscript, we have added a description of the literature search strategy, the databases used, the inclusion and exclusion criteria for literature, as well as the number of included studies in the introduction section (Lines 93-107).

4. The manuscript presents models but does not adequately discuss the main limitations. Table 2 lists a large number of statistical methods. However, it does not explain when each method should be used, its main advantages, and comparative limitations.

Ans: We greatly appreciate your professional review and valuable comments on our manuscript. We fully agree with your suggestions and have comprehensively revised Table 1 and Table 2 in the revised manuscript, including detailed descriptions of various quantitative formulas, the application scenarios of different research methods, their main advantages and research significance (Line 281 and Line 324).

5. In the conclusions, the main results of the review should be presented more clearly.

Ans: We sincerely appreciate the reviewer for pointing out the issues and providing valuable suggestions. We have integrated and revised the conclusion section of the manuscript to present the core research findings more clearly (Lines 836-869).

6. The sentences are too long, complex, and sometimes there is repetition of ideas, which can make reading difficult. The sentences should be shorter and more objective, and problems such as “突变特征” need to be corrected.

Ans: We appreciate the constructive comments provided by the reviewer and have carefully revised the manuscript accordingly. We have systematically organized and polished the language of the full text, and corrected the Chinese characters and related formatting issues throughout the manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

This manuscript takes on a worthwhile and timely review topic. The paper is trying to gather the conceptual basis of precipitation use efficiency, the main calculation approaches, the supporting analytical methods, the principal controlling factors, the practical routes to improvement, and the likely future direction of the field into one account. That is an ambitious undertaking, and the manuscript shows real effort in the breadth of literature assembled.

The strongest part of the paper sits in the middle. Section 2 gives the reader a useful conceptual ramp into precipitation use efficiency, and Section 3 then moves into formulae, variables, and analytical techniques in a way that gives the review a recognisable centre. Table 1 and Table 2 do much of the paper’s organisational work. Without them, the manuscript would read as a far looser overview.

What prevents the paper from landing as a fully convincing review is that the architecture of the review itself remains under-reported. There is no section explaining how the literature was identified, selected, or grouped. That omission matters because later claims about major drivers, preferred methods, research limitations, and future directions ask the reader to trust a synthesis process that is never made visible.

A second problem appears at both ends of the manuscript. The Abstract promises wide coverage, the final paragraph of the Introduction explains why the topic matters, and the Conclusion returns to broad significance, but none of those places states clearly enough what this review adds beyond assembling existing PUE themes. The manuscript shows scope more clearly than contribution.

Language and editorial control also hold the papr back. The title page contains irregular correspondence details, Section 3.2 includes an untranslated term, Section 6.2.3 is malformed, some figure and caption wording is awkward, and many sentences run too long. The paper has material worth developing, but it is not yet ready for external peer review. Major revision is required.

A. Title

The title names the subject accurately. A reader encountering it for the first time would understand immediately that the paper deals with precipitation use efficiency and that its central concerns are quantification methods and influencing factors. In that direct descriptive sense, the title is fit for purpose.

Even so, the wording remains broad and interchangeable. “Research Progress on” is familiar review language, but it gives the title very little identity of its own. A stronger title would tell the reader more precisely what sort of review this is, whether methodological, conceptual, driver-centred, or integrative across ecosystem contexts.

That lack of identity matters because the body of the paper actually covers more than the title presently signals. Section 2 deals with core conotation and ecological implications. Section 5 turns to practical enhancement approaches. Section 6 then moves into research limitations and future prospects. The title therefore captures two major components of the manuscript, but not the full shape of the review.

The present title also does not help the manuscript with its contribution problem. Since the review itself has not yet sharply defined its added value, the title becomes the first place where stronger positioning could help. At the moment it introduces the topic, but not the paper’s particular angle on that topic.

The title is therefore accurate but still too generic. It should be revised so that it identifies the paper more clearly as a review and better reflects the specific type of synthesis being attempted. At present it names the territory, but not the paper’s own stance within that territory.

B. Abstract

The Abstract gives a clear sense of the manuscript’s range. It moves from the ecological importance of precipitation, to vegetation productivity, to PUE as a measure, then through quantification methods, influencing factors, enhancement strategies, and future prospects. The reader is not left wondering what the paper intends to cover.

What the Abstract does not do well is discriminate between coverage and contribution. It reads as a compact tour through the paper rather than as a focused review abstract that tells the reader what has been clarified, compared, or newly synthesised. The claim that the paper “systematically reviews” and “deeply analyses” the field is not enough on its own.

The novelty problem is plain here. The Abstract says that the review covers definitions, methods, factors, and future directions, but it does not explain what this review contributes beyond bringing those elements together. If the manuscript’s added value lies in comparing formulae, drawing attention to scale-sensitive drivers, linking methodological choices to interpretation, or identifying unresolved weaknesses in current PUE research, that needs to be stated directly.

The keywords also need strengthening. “Precipitation use efficiency” and “net primary productivity” are central. “Quantification methods” and “influencing factors” are understandable but broad. “Regional sustainable development” is the weakest of the set because it does not sharpen the review’s actual analytical centre. A tighter keyword set would help define the paper more precisely.

At sentence level, the Abstrat needs considerable editing. It is built from long clause chains, and the final stretch becomes especially crowded, moving quickly from research limitations to future prospects to ecosystem resilience, regional water resource management, and sustainable ecological construction. That sweep is too wide for an abstract that still has not clearly stated the paper’s own contribution.

C. Introduction

The opening of the Introduction does useful work. It situates PUE within climate change, carbon and water cycles, water scarcity, and ecological functioning, which means the manuscript begins from a real scientific and practical problem rather than from a narrow technical definition. That broad framing is one of the paper’s assets.

The section also starts to show where PUE research has taken shape. References to dryland ecosystems, vegetation communities, and the Qinghai-Tibet Plateau begin to give the review some geographic and ecological texture. This helps the reader see that the literature is not evenly distributed across all systems.

The difficulty appears in how slowly the Introduction moves from topic importance to review purpose. Much of the section builds the general case for why precipitation and vegetation matter, but the paper takes too long to tell the reader why this review is needed in its present form. By the time the final paragraph arrives, the manuscript has still not clearly named the synthesis gap it intends to address.

The final paragraph is the key place where contribution should crystallise, yet it still reads mainly as a statement of significance and coverage. The manuscript says it will elaborate connotation, methods, influencing factors, enhancement strategies, and future directions, and that PUE has diagnostic, proxy, and technical value. Those points explain why the field matters, but they do not explain what this review is doing that is distinct.

The Introduction needs tightening and repositioning. More of the section should be spent on defining the review’s question, explaining the logic of the chosen structure, and stating the review’s contribution in direct terms. Less space should be used for broad thematic build-up that does not yet sharpen the manuscript’s own identity as a review article.

D. Materials and methods

This is the manuscript’s most serious structural weakness. For a review paper of this kind, a reader expects a clear account of how the literature base was assembled. Here, no dedicated review-method section is provided, and the paper therefore leaves its own synthesis procedure largely invisible.

That omission is not a formal nicety. It affects the reader’s confidence in the rest of the paper. When the manuscript later identifies major categories of influencing factors, outlines current limitations, or proposes future research directions, those claims depend on a literature base that has not been described in methodological terms.

Nothing in the paper explains which databases were searched, which time period was covered, what search terms were used, what languages or publication types were included, or how papers were judged relevant. There is also no acount of how the literature was grouped into the thematic structure now used in Sections 2 to 6. The review therefore asks for trust without showing its route.

This gap is visible in the paper’s internal organisation. The manuscript moves from concept, to methods, to drivers, to enhancement, to prospects, but does not explain why that architecture was chosen or whether it arose from a systematic literature-screening process. As a result, the review’s structure looks intuitive rather than demonstrably grounded.

A brief note in the Introduction would not solve this. The manuscript needs an actual review-method section. Until that is provided, the paper remains exposed at the precise point where a review article most needs to be secure: the link between a body of literature and the synthesis claims drawn from it.

 

 

 

E. Results

For a review manuscript, the nearest equivalent to results is the thematic synthesis carried by Sections 2 to 6. On that basis, this paper does contain a substantial body of assembled material. Section 2 sets out the conceptual basis of precipitation use efficiency through NPP, ANPP, BNPP, and related ecological meaning, while Section 3 gathers formulae and analytical approaches in a way that gives the review a workable centre.

The strongest “results-like” material sits in Table 1 and Table 2. Table 1 shows, in one place, that PUE is not being operationalised through a single settled formula, but through several forms linked to variables such as NPP, ANPP, BNPP, NDVI, SAVI, AGB, and GPP. That is a useful synthesis step. It helps the reader see immediately that interpretation of PUE is shaped by how it is quantified. Table 2 then extends this by bringing together trend analysis, threshold identification, machine learning, and related supporting methods.

The problem is that the text around these tables still does less analytical work than the tables invite. In Section 3.1 and Section 3.2, methods are introduced one after another, but the review too rarely pauses to say what the comparison means. The reader is shown that multiple approaches exist, yet is given less help in judging when one approach is preferable, what scale or data conditions shape that choice, or how different methods may lead to different readings of PUE behaviour.

A similar pattern appears in Section 4. The manuscript moves through temperature, precipitation, topography, soil and vegetation, and human intervention with wide coverage, and Table 3 adds a compact summary of meteorological influences. Even so, the section often proceeds by serial reporting. It gives examples of effects and thresholds, but less often distinguishes clearly between patterns that seem broadly stable and patterns that appear tied to particular ecosystems, regions, datasets, or analytical approaches.

The paper therefore has substantial synthesis material, but it has not yet converted that material into a strong set of review findings. Its middle sections are informative, especially where the tables stabilise the discussion, but the manuscript still needs firmer comparative judgement. The task now is not to add more examples, but to draw clearer conclusions from the examples already assembled.

F. Discussion

The discussion is spread across the latter parts of the manuscript rather than gathered into a single tightly bounded interpretive section. That is not automatically a flaw, but here it does make the manuscript’s voice less controlled. The paper moves repeatedly from reporting what studies have found to stating what the field means, and that transition is not always clearly signalled.

The manuscript is most convincing when it treats PUE as the product of interacting controls rather than a single climatic response. In Section 4, the paper shows reasonably well that precipitation alone does not explain the literature, because temperature, topography, vegetation structure, soil properties, and human intervention are all drawn into the picture. Those passages give the review some intellectual grip and prevent the discussion from collapsing into a one-factor story.

Section 3.2 is more mixed. The review introduces methods such as Sen’s slope with Mann-Kendall testing, piecewise linear regression, Random Forest, SHAP, grey relational analysis, and structural equation modelling, and these are clearly relevant to recent PUE work. The difficulty is that the manuscript often presents them as though their comparative explanatory value has already been established by the review. The paper shows that these tools are being used, but it does not yet assess with enough care what each method contributes, where its interpretive limits lie, or how much confidence the review itself places in those outputs.

The same looseness appears in Section 6. The future-oriented discussion of interdisciplinary research, large-span remote sensing, and “human-environment-economy” coordinated development is energetic, but the bridge into these proposals is not always fully earned. The review does not consistently show that these directions arise from clearly demonstrated weaknesses, contradictions, or absences in the literature surveyed earlier. At times the prose moves ahead of the synthesis.

This section would therefore benefit from firmer interpretive restraint. The manuscript should indicate more clearly which conclusions emerge securely from the reviewed literature, which remain context-bound, and which belong more properly to forward-looking proposal. Once that boundary is made clearer, the discussion will feel less expansive for its own sake and more convincingly tied to the evidence assembled in the body of the paper.

G. Conclusion

The Conclusion returns to the core subject and does give the paper a recognisable closure. It reminds the reader that PUE links carbon and water processes and that the manuscript has addressed connotation, methods, influencing factors, enhancement approaches, and future prospects. It is therefore more than a simple stopping point.

Its main weakness is that it still reads as a summary of what the paper has covered rather than as a precise statement of what the review has established. The section names the terrain again, but it does not leave the reader with a strongly defined sense of what has become clearer because this review exists.

That is where the contribution problem is most visible. A review conclusion should not only restate topic importance. It should identify the strongest synthesis outcomes. For example, if the review’s main finding is that PUE interpretation shifts materially with formula choice, or that climatic drivers interact with vegetation and soil context in ways that resist simple generalisation, or that the field is methodologically rich but review-methodologically weak, those kinds of synthesis claims should appear clearly here.

The Conclusion also broadens quickly into wider significance. References to ecosystem service functions, resilience, water-resource management, and sustainable ecological construction are understandable, but the section would be stronger if it first stabilised its own evidence-led conclusions before moving outward into larger implication.

This section therefore needs more selectivity and more discipline. It should state the review’s contribution explicitly, identify the most defensible synthesis insights, and avoid enlarging the paper’s claims beyond what the review has clearly established in the body of the manuscript.

H. Tables and figures

The tables and figures are important to this paper. They are not decorative additions. Table 1, Table 2, Table 3, Figure 1, Figure 2, and Figure 3 carry much of the manuscript’s organising burden and help prevent the review from dissolving into continuous prose.

Table 1 is one of the strongest elements in the paper because it makes visible the diversity of PUE formulae and associated variables. By placing NPP-, ANPP-, NDVI-, SAVI-, AGB-, and GPP-related formulations side by side, it gives the review a platform for methodological comparison. The problem is that the surrounding text does not yet exploit that platform fully.

Table 2 is ambitious and potentially very valuable, but it is too dense in its present form. It extends across pages and compiles a large amount of information about methods and principles. That breadth is useful, yet the table also becomes difficult to navigate, and the reader is left needing clearer textual guidance on what to take from the comparison. Simplifying or restructuring it would help.

The figures are conceptually energetic, especially Figure 2 and Figure 3, but they are not equally readable. Figure 2 carries a great deal of conceptual traffic and risks becoming schematic rather than explanatory. Figure 3 is cleaner and more manageable, although its relationship to the preceding discussion could be more sharply drawn in the text.

Several visible presentation details need correction. The caption wording is not fully settled, “Ecological Sta- bility” is awkwardly broken, and the in-text reference “As shown in Figure 3.” is left as a sentence fragment. These may look small, but they matter because tables and figures are often where reviewers first test whether a manuscript is under editorial control. Here, the visual layer is useful, but not yet fully polished.

I. Language, units, and style

Language is one of the main reasons the manuscript still reads as pre-peer-review rather than submission-ready. Many sentences are long, clause-heavy, and over-connected by commas. Meaning is often present, but the prose makes the reader work harder than necessary to reach it.

The English is also uneven. Some passages are clear enough, though still wordy. Others sound translated or insufficiently edited into stable academic English. The Abstract contains several such stretches, and the phrase “It’s significance” in the Introduction is a visible example of weak editorial finishing. Similar instability appears later in the paper, especially when several ideas are packed into one sentence.

There are also direct local faults that need correction. Section 3.2 includes the untranslated term “突变特征”. Section 6.2.3 appears as 6.2.3". Human-Environment-Economy" Coordinated Development, which is plainly malformed. The title-page correspondence line is irregular, with e-mail presentation that does not look publication-ready, and the telephone formatting is similarly awkward.

Units and notation are less problematic than the prose, but they still require checking. Because the manuscript deals so heavily with formulae, indices, and quantitative interpretation, consistency of symbols, subscripts, and notation matters. Table 1 in particular should be checked carefully for character conversion problems and for the clarity of formula presentation.

What this paper needs is not merely copy-editing. It needs language revision at manuscript level. Sentences should be shortened, paragraphing made more disciplined, repetition reduced, and rhetorical inflation trimmed back. Until that happens, the paper’s substantive content will continue to be undermined by the way it is expressed.

J. References and citations

The in-text citation system is consistent. Numerical citations are used throughout, and the manuscript does not generally advance literature-based claims without giving some source support. That gives the paper a workable scholarly frame and suggests that the reading base is substantial rather than incidental.

Using the publication years visible in the reference list, the references span 1998 to 2025, with a median year of 2020. The list is therefore not obviously dated, and it includes a considerable amount of recent literature. That is a positive feature for a review article in an area shaped by changing analytical methods, expanding regional studies, and continuing debate about how precipitation-use efficiency should be interpreted.

The year distribution is not evenly spread. The references are weighted strongly towards the 2010s and 2020s, and 2025 appears frequently in the present list. The recent-literature share is therefore strong, with roughly three quarters of the references falling within the preceding ten-year window when measured against the most recent visible reference year. That indicates that the paper is bibliographically current. The caution is not that the list is old, but that very recent references should be checked carefully to ensure that they remain stable, accurate, and correctly formatted at the point of submission.

The larger issue is balance rather than recency. The reference base is clearly relevant to the manuscript and thematically coherent, with strong coverage of precipitation-use efficiency, rain-use efficiency, grassland productivity, alpine and plateau systems, and associated ecological or remote-sensing work. That topical consistency supports the manuscript well. At the same time, the bibliography appears concentrated in Chinese, grassland, alpine, plateau, and dryland contexts, which fits the manuscript’s content but narrows the sense of a broader global synthesis. If the review intends to speak more widely than those contexts, the source base may need some widening or at least a clearer acknowledgement of its centre of gravity.

The references therefore look current enough, but they still need a careful final check for spread, consistency, and presentation. Journal titles, capitalisation, and general style should be standardised across the list, and the authors should confirm that the bibliography remains current at submission stage. They should also check that the source base is not narrower than the review intends to suggest, especially where the manuscript moves from regional evidence towards broader conceptual or methodological claims.

K. Transparency and end matter

The standard end sections are present. Author Contributions, Funding, Institutional Review Board Statement, Data Availability Statement, Acknowledgments, and Conflicts of Interest all appear, so the paper does not end abruptly after the Conclusion. In formal terms, the manuscript has the expected template components.

The deeper transparency problem, however, lies earlier in the paper. No amount of end matter can compensate for the missing review-method account. Since the manuscript is a review article, the most important transparency requirement is a clear explanation of how the literature was assembled and organised. That remains absent.

Within the end matter itself, the Data Availability Statement is the weakest fit. “The raw data supporting the conclusions of this article will be made available by the authors on request” sounds more appropriate for an empirical study than for a review. If the authors mean that their review dataset, literature matrix, or screening record can be shared, then that needs to be stated directly.

The Conflicts of Interest wording also deserves attention. “The remaining authors declare” sounds odd in the present form and gives the impression that some earlier declaration may have been separated out, even though that is not evident in the manuscript. The Acknowledgments section is also close in function to the Funding statement and would benefit from clearer differentiation.

Overall, the manuscript looks formally equipped but not yet fully transparent. The visible end sections are there, but the core review transparency that would allow the reader to trust the synthesis process has not yet been provided. That remains the more serious problem.

L. Priority revisions

The first priority is to add a proper review-method section. Until the paper explains how studies were located, selected, screened, and grouped, the rest of the review remains methodologically exposed. This is the revision that would do the most to improve trust in the manuscript.

The next priority is to define the paper’s contribution much more sharply. The Abstract, the final paragraph of the Introduction, and the Conclusion should each state clearly what this review adds. At present the manuscript promises wide coverage but does not yet name its distinct synthesis value in direct terms.

The third priority is analytical tightening in the body of the review, especially in Sections 3 and 4. The paper already has substantial material there, but it still leans too heavily on serial summary. More comparative judgement is needed, along with clearer indication of where findings are robust, where they are context-bound, and where method choice affects interpretation.

Language revision must then be done thoroughly and not as a cosmetic afterthought. The malformed heading in Section 6.2.3, the untranslated term in Section 3.2, the irregular title-page correspondence line, the sentence fragment around Figure 3, and the long clause-heavy sentence structure throughout the manuscript all require careful correction.

Finally, the visual and bibliographic elements should be brought into closer alignment with the revised argument. Table 2 needs simplification or sharper use, figure captions and figure references need correction, the Data Availability Statement should be rewritten to suit a review article, and the reference list should be checked for consistency and balance. Those changes would make the paper much more coherent as a whole.

M. Overall readiness and contribution

This manuscript is not yet ready for external peer review. That conclusion rests mainly on three connected weaknesses visible across the paper: no reported review methodology, no sharply stated review contribution in the Abstract, Introduction, and Conclusion, and too much reliance on descriptive accumulation in the central synthesis sections. Those are not minor blemishes. They affect the credibility of the review as a scholarly article.

At the same time, the paper is not thin. Section 2 gives it a conceptual base, and Section 3 contains genuinely useful material, especially in Table 1 and Table 2, where the manuscript comes closest to offering comparative synthesis rather than general overview. Section 4 also shows that the authors understand that PUE is shaped by interacting drivers rather than by a single rainfall signal. There is real substance here.

What remains underdeveloped is the manuscript’s own added value. The paper shows that the authors have read widely and can organise the field into recognisable themes, but it still does not tell the reader clearly enough what has become more intelligible because of this review. At present the manuscript offers breadth, but not yet a sufficiently named or defended contribution.

Editorial readiness is also below the level expected for submission. The untranslated term in Section 3.2, the malformed heading in Section 6.2.3, the irregular correspondence details on the title page, and the uneven sentence control throughout the manuscript all reinforce the impression that the paper has not yet been fully stabilised. These problems do not define the manuscript, but they do weaken confidence in it.

My overall judgement therefore remains unchanged, though it can now be stated more tightly. The manuscript has a workable core, particularly in its conceptual and methodological middle sections, but that core is still surrounded by structural and editorial weakness. Major revision is required, with priority given to review-method transparency, contribution framing, stronger comparative synthesis, and full language revision.

 

N. Evidential spine interpretation

The manuscript is strongest in the route running from Section 2 into Section 3. The conceptual framing of PUE, the discussion of productivity measures, and the transition into formulae and supporting methods create the clearest internal chain in the paper. Here the review feels as though it is building from concept to quantification in a reasonably ordered way.

That chain continues, though less securely, into the opening of Section 4. Once the manuscript begins mapping meteorological, topographic, vegetation-soil, and human-intervention factors, the paper still has some structural grip because the reader can see how the field is being partitioned. Table 3 helps stabilise this part, even if it is narrower than Table 1 and Table 2 in overall contribution.

The chain weakens near the start because the paper does not define its own review purpose sharply enough. The Abstract and Introduction explain why PUE matters and what themes will be covered, but they do not establish a crisp review question or a clearly named review contribution. The opening therefore carries importance more strongly than identity.

The most serious break appears where the review method should stand. Because the manuscript does not explain how the literature base was built, the bridge between reading and synthesis remains insufficiently visible. That weakens confidence in the paper’s later claims about major factors, limitations, and future directions. It is the most exposed point in the manuscript’s argumentative chain.

A second weakening appears at the close. The Conclusion returns to significance and future need, but it does not distil the review’s strongest evidence-led insights with enough precision. In effect, the manuscript has a stronger middle than beginning or end. It would become much more coherent if it defined its contribution more clearly at the front, made its synthesis process transparent in the middle, and concluded with a more exact statement of what the review has actually established.

Overall recommendation

Major revision required.

Comments on the Quality of English Language

See report

Author Response

1. This manuscript takes on a worthwhile and timely review topic. The paper is trying to gather the conceptual basis of precipitation use efficiency, the main calculation approaches, the supporting analytical methods, the principal controlling factors, the practical routes to improvement, and the likely future direction of the field into one account. That is an ambitious undertaking, and the manuscript shows real effort in the breadth of literature assembled. The strongest part of the paper sits in the middle. Section 2 gives the reader a useful conceptual ramp into precipitation use efficiency, and Section 3 then moves into formulae, variables, and analytical techniques in a way that gives the review a recognisable centre. Table 1 and Table 2 do much of the paper’s organisational work. Without them, the manuscript would read as a far looser overview.

What prevents the paper from landing as a fully convincing review is that the architecture of the review itself remains under-reported. There is no section explaining how the literature was identified, selected, or grouped. That omission matters because later claims about major drivers, preferred methods, research limitations, and future directions ask the reader to trust a synthesis process that is never made visible. A second problem appears at both ends of the manuscript. The Abstract promises wide coverage, the final paragraph of the Introduction explains why the topic matters, and the Conclusion returns to broad significance, but none of those places states clearly enough what this review adds beyond assembling existing PUE themes. The manuscript shows scope more clearly than contribution. Language and editorial control also hold the paper back. The title page contains irregular correspondence details, Section 3.2 includes an untranslated term, Section 6.2.3 is malformed, some figure and caption wording is awkward, and many sentences run too long. The paper has material worth developing, but it is not yet ready for external peer review. Major revision is required.

Ans: We sincerely appreciate the reviewer for the detailed and constructive comments on our review manuscript, as well as the recognition of its topic value, literature collection, framework structure and key tables. Your objective evaluation of the strengths and shortcomings provides us with crucial guidance for further improvement.

2. A. Title

The title names the subject accurately. A reader encountering it for the first time would understand immediately that the paper deals with precipitation use efficiency and that its central concerns are quantification methods and influencing factors. In that direct descriptive sense, the title is fit for purpose. Even so, the wording remains broad and interchangeable. “Research Progress on” is familiar review language, but it gives the title very little identity of its own. A stronger title would tell the reader more precisely what sort of review this is, whether methodological, conceptual, driver-centred, or integrative across ecosystem contexts. That lack of identity matters because the body of the paper actually covers more than the title presently signals. Section 2 deals with core co-notation and ecological implications. Section 5 turns to practical enhancement approaches. Section 6 then moves into research limitations and future prospects. The title therefore captures two major components of the manuscript, but not the full shape of the review. The present title also does not help the manuscript with its contribution problem. Since the review itself has not yet sharply defined its added value, the title becomes the first place where stronger positioning could help. At the moment it introduces the topic, but not the paper’s particular angle on that topic. The title is therefore accurate but still too generic. It should be revised so that it identifies the paper more clearly as a review and better reflects the specific type of synthesis being attempted. At present it names the territory, but not the paper’s own stance within that territory.

Ans: We appreciate your careful review and valuable comments on our manuscript, which have played an important role in improving our paper. We have revised the title according to your suggestions, and the improved title can clearly indicate that this is a review article and reflect the core purpose of the study (Lines 2-3).

3. B. Abstract

The Abstract gives a clear sense of the manuscript’s range. It moves from the ecological importance of precipitation, to vegetation productivity, to PUE as a measure, then through quantification methods, influencing factors, enhancement strategies, and future prospects. The reader is not left wondering what the paper intends to cover. What the Abstract does not do well is discriminate between coverage and contribution. It reads as a compact tour through the paper rather than as a focused review abstract that tells the reader what has been clarified, compared, or newly synthesised. The claim that the paper “systematically reviews” and “deeply analyses” the field is not enough on its own. The novelty problem is plain here. The Abstract says that the review covers definitions, methods, factors, and future directions, but it does not explain what this review contributes beyond bringing those elements together. If the manuscript’s added value lies in comparing formulae, drawing attention to scale-sensitive drivers, linking methodological choices to interpretation, or identifying unresolved weaknesses in current PUE research, that needs to be stated directly. The keywords also need strengthening. “Precipitation use efficiency” and “net primary productivity” are central. “Quantification methods” and “influencing factors” are understandable but broad. “Regional sustainable development” is the weakest of the set because it does not sharpen the review’s actual analytical centre. A tighter keyword set would help define the paper more precisely. At sentence level, the Abstrat needs considerable editing. It is built from long clause chains, and the final stretch becomes especially crowded, moving quickly from research limitations to future prospects to ecosystem resilience, regional water resource management, and sustainable ecological construction. That sweep is too wide for an abstract that still has not clearly stated the paper’s own contribution.

Ans: We thank the reviewer for the thoughtful review and constructive feedback. We have revised the manuscript according to your comments and reorganized the abstract and keywords as requested (Lines 17-43 and Line 45).

4. C. Introduction

The opening of the Introduction does useful work. It situates PUE within climate change, carbon and water cycles, water scarcity, and ecological functioning, which means the manuscript begins from a real scientific and practical problem rather than from a narrow technical definition. That broad framing is one of the paper’s assets. The section also starts to show where PUE research has taken shape. References to dryland ecosystems, vegetation communities, and the Qinghai-Tibet Plateau begin to give the review some geographic and ecological texture. This helps the reader see that the literature is not evenly distributed across all systems. The difficulty appears in how slowly the Introduction moves from topic importance to review purpose. Much of the section builds the general case for why precipitation and vegetation matter, but the paper takes too long to tell the reader why this review is needed in its present form. By the time the final paragraph arrives, the manuscript has still not clearly named the synthesis gap it intends to address. The final paragraph is the key place where contribution should crystallise, yet it still reads mainly as a statement of significance and coverage. The manuscript says it will elaborate connotation, methods, influencing factors, enhancement strategies, and future directions, and that PUE has diagnostic, proxy, and technical value. Those points explain why the field matters, but they do not explain what this review is doing that is distinct. The Introduction needs tightening and repositioning. More of the section should be spent on defining the review’s question, explaining the logic of the chosen structure, and stating the review’s contribution in direct terms. Less space should be used for broad thematic build-up that does not yet sharpen the manuscript’s own identity as a review article.

Ans: We sincerely appreciate the reviewer’s careful reading and valuable feedback. We have carefully revised the manuscript in response to your comments that "the transition from the importance of the topic to the purpose of the review in the introduction is too slow" and that "more effort should be made to clarify the research questions of the review, explain the logic of the chosen structure, and explicitly state the contribution of the review". We have reduced overly general background introductions to make the flow more concise and focused (Lines 47-125).

5. D. Materials and methods

This is the manuscript’s most serious structural weakness. For a review paper of this kind, a reader expects a clear account of how the literature base was assembled. Here, no dedicated review-method section is provided, and the paper therefore leaves its own synthesis procedure largely invisible. That omission is not a formal nicety. It affects the reader’s confidence in the rest of the paper. When the manuscript later identifies major categories of influencing factors, outlines current limitations, or proposes future research directions, those claims depend on a literature base that has not been described in methodological terms. Nothing in the paper explains which databases were searched, which time period was covered, what search terms were used, what languages or publication types were included, or how papers were judged relevant. There is also no acount of how the literature was grouped into the thematic structure now used in Sections 2 to 6. The review therefore asks for trust without showing its route. This gap is visible in the paper’s internal organisation. The manuscript moves from concept, to methods, to drivers, to enhancement, to prospects, but does not explain why that architecture was chosen or whether it arose from a systematic literature-screening process. As a result, the review’s structure looks intuitive rather than demonstrably grounded. A brief note in the Introduction would not solve this. The manuscript needs an actual review-method section. Until that is provided, the paper remains exposed at the precise point where a review article most needs to be secure: the link between a body of literature and the synthesis claims drawn from it.

Ans: We sincerely appreciate the reviewer’s careful review and valuable comments. In the revised manuscript, we have supplemented the introduction section with a detailed description of the literature search strategy, the employed databases, the literature inclusion and exclusion criteria, as well as the quantity of the finally included studies (Lines 93-107).

6. E. Results

For a review manuscript, the nearest equivalent to results is the thematic synthesis carried by Sections 2 to 6. On that basis, this paper does contain a substantial body of assembled material. Section 2 sets out the conceptual basis of precipitation use efficiency through NPP, ANPP, BNPP, and related ecological meaning, while Section 3 gathers formulae and analytical approaches in a way that gives the review a workable centre. The strongest “results-like” material sits in Table 1 and Table 2. Table 1 shows, in one place, that PUE is not being operationalised through a single settled formula, but through several forms linked to variables such as NPP, ANPP, BNPP, NDVI, SAVI, AGB, and GPP. That is a useful synthesis step. It helps the reader see immediately that interpretation of PUE is shaped by how it is quantified. Table 2 then extends this by bringing together trend analysis, threshold identification, machine learning, and related supporting methods. The problem is that the text around these tables still does less analytical work than the tables invite. In Section 3.1 and Section 3.2, methods are introduced one after another, but the review too rarely pauses to say what the comparison means. The reader is shown that multiple approaches exist, yet is given less help in judging when one approach is preferable, what scale or data conditions shape that choice, or how different methods may lead to different readings of PUE behaviour.

A similar pattern appears in Section 4. The manuscript moves through temperature, precipitation, topography, soil and vegetation, and human intervention with wide coverage, and Table 3 adds a compact summary of meteorological influences. Even so, the section often proceeds by serial reporting. It gives examples of effects and thresholds, but less often distinguishes clearly between patterns that seem broadly stable and patterns that appear tied to particular ecosystems, regions, datasets, or analytical approaches. The paper therefore has substantial synthesis material, but it has not yet converted that material into a strong set of review findings. Its middle sections are informative, especially where the tables stabilise the discussion, but the manuscript still needs firmer comparative judgement. The task now is not to add more examples, but to draw clearer conclusions from the examples already assembled.

Ans: We greatly appreciate your professional review and constructive comments on our manuscript. We fully accept your suggestions and have comprehensively revised Table 1 and Table 2 in the revised version. Specifically, we have supplemented detailed descriptions of various quantitative formulas, the application scenarios of different research methods, their main advantages and research significance (as shown in Line 281 and Line 324).

We appreciate the opportunity to clarify this point. Table 3 only provides a brief summary of other minor meteorological factors regulating precipitation use efficiency (PUE), without emphasizing the dominant influencing factors. The general patterns of the main driving factors have been clearly summarized in the preceding text (Line 433).

7. F. Discussion

The discussion is spread across the latter parts of the manuscript rather than gathered into a single tightly bounded interpretive section. That is not automatically a flaw, but here it does make the manuscript’s voice less controlled. The paper moves repeatedly from reporting what studies have found to stating what the field means, and that transition is not always clearly signalled. The manuscript is most convincing when it treats PUE as the product of interacting controls rather than a single climatic response. In Section 4, the paper shows reasonably well that precipitation alone does not explain the literature, because temperature, topography, vegetation structure, soil properties, and human intervention are all drawn into the picture. Those passages give the review some intellectual grip and prevent the discussion from collapsing into a one-factor story.

Section 3.2 is more mixed. The review introduces methods such as Sen’s slope with Mann-Kendall testing, piecewise linear regression, Random Forest, SHAP, grey relational analysis, and structural equation modelling, and these are clearly relevant to recent PUE work. The difficulty is that the manuscript often presents them as though their comparative explanatory value has already been established by the review. The paper shows that these tools are being used, but it does not yet assess with enough care what each method contributes, where its interpretive limits lie, or how much confidence the review itself places in those outputs. The same looseness appears in Section 6. The future-oriented discussion of interdisciplinary research, large-span remote sensing, and “human-environment-economy” coordinated development is energetic, but the bridge into these proposals is not always fully earned. The review does not consistently show that these directions arise from clearly demonstrated weaknesses, contradictions, or absences in the literature surveyed earlier. At times the prose moves ahead of the synthesis. This section would therefore benefit from firmer interpretive restraint. The manuscript should indicate more clearly which conclusions emerge securely from the reviewed literature, which remain context-bound, and which belong more properly to forward-looking proposal. Once that boundary is made clearer, the discussion will feel less expansive for its own sake and more convincingly tied to the evidence assembled in the body of the paper.

Ans: We are grateful to the reviewer for the insightful and valuable comments. After careful consideration, we have revised and improved the manuscript accordingly. A new Section 5, “Comprehensive Discussion of Driving Factors”, has been added, in which we elaborate the interactions among driving factors, as well as the response of precipitation use efficiency (PUE) to variations in water and heat conditions under future climate scenarios (Lines 558–663).

We are deeply grateful to you for the professional review of our paper and the constructive comments provided. We fully accept your suggestions and have comprehensively revised Table 2 in the revised manuscript. Specifically, we have supplemented the application scenarios, main advantages and research significance of different research methods, to further improve the completeness and rigor of the table (Line 324).

Thank you very much for your valuable suggestions. We have carefully integrated and revised this section in response to your comments that "the review does not consistently demonstrate how these research directions stem from specific deficiencies, contradictions, or gaps explicitly presented in the surveyed literature, and that the advancement of the discussion goes beyond the scope of comprehensive analysis." (Lines 691-834).

8. G. Conclusion

The Conclusion returns to the core subject and does give the paper a recognisable closure. It reminds the reader that PUE links carbon and water processes and that the manuscript has addressed connotation, methods, influencing factors, enhancement approaches, and future prospects. It is therefore more than a simple stopping point. Its main weakness is that it still reads as a summary of what the paper has covered rather than as a precise statement of what the review has established. The section names the terrain again, but it does not leave the reader with a strongly defined sense of what has become clearer because this review exists. That is where the contribution problem is most visible. A review conclusion should not only restate topic importance. It should identify the strongest synthesis outcomes. For example, if the review’s main finding is that PUE interpretation shifts materially with formula choice, or that climatic drivers interact with vegetation and soil context in ways that resist simple generalisation, or that the field is methodologically rich but review-methodologically weak, those kinds of synthesis claims should appear clearly here. The Conclusion also broadens quickly into wider significance. References to ecosystem service functions, resilience, water-resource management, and sustainable ecological construction are understandable, but the section would be stronger if it first stabilised its own evidence-led conclusions before moving outward into larger implication. This section therefore needs more selectivity and more discipline. It should state the review’s contribution explicitly, identify the most defensible synthesis insights, and avoid enlarging the paper’s claims beyond what the review has clearly established in the body of the manuscript.

Ans: We sincerely appreciate the reviewer for pointing out the issues and providing valuable suggestions. We have integrated and revised the conclusion section of the manuscript by presenting the core research findings in a point-by-point manner, which makes the presentation clearer, more concise and more logical (Lines 836-869).

9. H. Tables and figures

The tables and figures are important to this paper. They are not decorative additions. Table 1, Table 2, Table 3, Figure 1, Figure 2, and Figure 3 carry much of the manuscript organising burden and help prevent the review from dissolving into continuous prose.

Table 1 is one of the strongest elements in the paper because it makes visible the diversity of PUE formulae and associated variables. By placing NPP-, ANPP-, NDVI-, SAVI-, AGB-, and GPP-related formulations side by side, it gives the review a platform for methodological comparison. The problem is that the surrounding text does not yet exploit that platform fully. Table 2 is ambitious and potentially very valuable, but it is too dense in its present form. It extends across pages and compiles a large amount of information about methods and principles. That breadth is useful, yet the table also becomes difficult to navigate, and the reader is left needing clearer textual guidance on what to take from the comparison. Simplifying or restructuring it would help. The figures are conceptually energetic, especially Figure 2 and Figure 3, but they are not equally readable. Figure 2 carries a great deal of conceptual traffic and risks becoming schematic rather than explanatory. Figure 3 is cleaner and more manageable, although its relationship to the preceding discussion could be more sharply drawn in the text. Several visible presentation details need correction. The caption wording is not fully settled, “Ecological Stability” is awkwardly broken, and the in-text reference “As shown in Figure 3.” is left as a sentence fragment. These may look small, but they matter because tables and figures are often where reviewers first test whether a manuscript is under editorial control. Here, the visual layer is useful, but not yet fully polished.

Ans: We sincerely appreciate the expert comments and valuable suggestions. All tables and figures in the manuscript have been carefully revised accordingly. The information presented in Figure 2 has been further elaborated and clarified in the main text (Lines 346–366). Figure 3 illustrates the practical measures for improving precipitation use efficiency in real-world applications (Line 690).

10. I. Language, units, and style

Language is one of the main reasons the manuscript still reads as pre-peer-review rather than submission-ready. Many sentences are long, clause-heavy, and over-connected by commas. Meaning is often present, but the prose makes the reader work harder than necessary to reach it. The English is also uneven. Some passages are clear enough, though still wordy. Others sound translated or insufficiently edited into stable academic English. The Abstract contains several such stretches, and the phrase “It’s significance” in the Introduction is a visible example of weak editorial finishing. Similar instability appears later in the paper, especially when several ideas are packed into one sentence.

There are also direct local faults that need correction. Section 3.2 includes the untranslated term “突变特征”. Section 6.2.3 appears as 6.2.3". Human-Environment-Economy" Coordinated Development, which is plainly malformed. The title-page correspondence line is irregular, with e-mail presentation that does not look publication-ready, and the telephone formatting is similarly awkward. Units and notation are less problematic than the prose, but they still require checking. Because the manuscript deals so heavily with formulae, indices, and quantitative interpretation, consistency of symbols, subscripts, and notation matters. Table 1 in particular should be checked carefully for character conversion problems and for the clarity of formula presentation.

What this paper needs is not merely copy-editing. It needs language revision at manuscript level. Sentences should be shortened, paragraphing made more disciplined, repetition reduced, and rhetorical inflation trimmed back. Until that happens, the paper’s substantive content will continue to be undermined by the way it is expressed.

Ans: We appreciate the constructive comments provided by the reviewer and have carefully revised the manuscript accordingly. We have systematically organized and polished the language of the full text, and corrected the Chinese characters and related formatting issues throughout the manuscript.

11. J. References and citations

The in-text citation system is consistent. Numerical citations are used throughout, and the manuscript does not generally advance literature-based claims without giving some source support. That gives the paper a workable scholarly frame and suggests that the reading base is substantial rather than incidental. Using the publication years visible in the reference list, the references span 1998 to 2025, with a median year of 2020. The list is therefore not obviously dated, and it includes a considerable amount of recent literature. That is a positive feature for a review article in an area shaped by changing analytical methods, expanding regional studies, and continuing debate about how precipitation-use efficiency should be interpreted. The year distribution is not evenly spread. The references are weighted strongly towards the 2010s and 2020s, and 2025 appears frequently in the present list. The recent-literature share is therefore strong, with roughly three quarters of the references falling within the preceding ten-year window when measured against the most recent visible reference year. That indicates that the paper is bibliographically current. The caution is not that the list is old, but that very recent references should be checked carefully to ensure that they remain stable, accurate, and correctly formatted at the point of submission. The larger issue is balance rather than recency. The reference base is clearly relevant to the manuscript and thematically coherent, with strong coverage of precipitation-use efficiency, rain-use efficiency, grassland productivity, alpine and plateau systems, and associated ecological or remote-sensing work. That topical consistency supports the manuscript well. At the same time, the bibliography appears concentrated in Chinese, grassland, alpine, plateau, and dryland contexts, which fits the manuscript’s content but narrows the sense of a broader global synthesis. If the review intends to speak more widely than those contexts, the source base may need some widening or at least a clearer acknowledgement of its centre of gravity. The references therefore look current enough, but they still need a careful final check for spread, consistency, and presentation. Journal titles, capitalisation, and general style should be standardised across the list, and the authors should confirm that the bibliography remains current at submission stage. They should also check that the source base is not narrower than the review intends to suggest, especially where the manuscript moves from regional evidence towards broader conceptual or methodological claims.

Ans: We sincerely appreciate your valuable comments. We would like to provide a brief explanation here. Based on the selected literature, this review summarizes that the majority of studies on precipitation use efficiency (PUE) have been conducted in the alpine ecological regions of the Qinghai-Tibet Plateau and dryland ecosystems worldwide, and the review analysis was carried out accordingly (Lines 68-71).

We sincerely appreciate the reviewer's constructive suggestions. The reference list has been carefully revised in accordance with the journal’s formatting requirements. Given that this study focuses on global precipitation use efficiency, we have also rigorously checked the relevance and consistency between all references and the main text (Lines 888–986).

12. K. Transparency and end matter

The standard end sections are present. Author Contributions, Funding, Institutional Review Board Statement, Data Availability Statement, Acknowledgments, and Conflicts of Interest all appear, so the paper does not end abruptly after the Conclusion. In formal terms, the manuscript has the expected template components. The deeper transparency problem, however, lies earlier in the paper. No amount of end matter can compensate for the missing review-method account. Since the manuscript is a review article, the most important transparency requirement is a clear explanation of how the literature was assembled and organised. That remains absent. Within the end matter itself, the Data Availability Statement is the weakest fit. “The raw data supporting the conclusions of this article will be made available by the authors on request” sounds more appropriate for an empirical study than for a review. If the authors mean that their review dataset, literature matrix, or screening record can be shared, then that needs to be stated directly. The Conflicts of Interest wording also deserves attention. “The remaining authors declare” sounds odd in the present form and gives the impression that some earlier declaration may have been separated out, even though that is not evident in the manuscript. The Acknowledgments section is also close in function to the Funding statement and would benefit from clearer differentiation. Overall, the manuscript looks formally equipped but not yet fully transparent. The visible end sections are there, but the core review transparency that would allow the reader to trust the synthesis process has not yet been provided. That remains the more serious problem.

Ans: We sincerely appreciate the expert’s careful guidance and valuable suggestions. The acknowledgments and conflict of interest statements have been comprehensively and meticulously revised in strict accordance with your requirements to ensure standardized and error-free presentation (Lines 881–886).

13. L. Priority revisions

The first priority is to add a proper review-method section. Until the paper explains how studies were located, selected, screened, and grouped, the rest of the review remains methodologically exposed. This is the revision that would do the most to improve trust in the manuscript. The next priority is to define the paper’s contribution much more sharply. The Abstract, the final paragraph of the Introduction, and the Conclusion should each state clearly what this review adds. At present the manuscript promises wide coverage but does not yet name its distinct synthesis value in direct terms. The third priority is analytical tightening in the body of the review, especially in Sections 3 and 4. The paper already has substantial material there, but it still leans too heavily on serial summary. More comparative judgement is needed, along with clearer indication of where findings are robust, where they are context-bound, and where method choice affects interpretation. Language revision must then be done thoroughly and not as a cosmetic afterthought. The malformed heading in Section 6.2.3, the untranslated term in Section 3.2, the irregular title-page correspondence line, the sentence fragment around Figure 3, and the long clause-heavy sentence structure throughout the manuscript all require careful correction. Finally, the visual and bibliographic elements should be brought into closer alignment with the revised argument. Table 2 needs simplification or sharper use, figure captions and figure references need correction, the Data Availability Statement should be rewritten to suit a review article, and the reference list should be checked for consistency and balance. Those changes would make the paper much more coherent as a whole.

Ans: We sincerely appreciate the reviewer’s valuable and professional comments. In accordance with the expert requirements, we have added a standardized section on review methodology, precisely defined the research contributions of this paper, tightened the analytical arguments in the main text, and carried out comprehensive linguistic polishing, rather than merely superficial revisions.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript has met the publication standards for academic journals.

Author Response

Dear Reviewer

    We sincerely appreciate your thorough review and valuable comments on the initial version of our manuscript, which have greatly guided us to improve the quality of this work. For the second revision, we have carefully addressed all the concerns you raised previously. We are deeply grateful that you have no further comments on the revised manuscript, and your recognition is a great encouragement to us.

Reviewer 2 Report

Comments and Suggestions for Authors

--

Author Response

Dear Reviewer

    We would like to express our heartfelt gratitude for your professional evaluation and constructive suggestions during the first round of review. These insightful opinions have helped us optimize the manuscript significantly. We are extremely thankful that you are satisfied with the revised content and have no additional comments. Your affirmation provides strong support for the improvement of our research.

Reviewer 3 Report

Comments and Suggestions for Authors

This revised review manuscript is stronger than the earlier version and is no longer exposed in quite the same way at the front and back ends. The title now identifies the paper more clearly as a review, the Introduction now contains an explicit literature-search paragraph, the body has been expanded through a new integrative discussion section, and the Conclusion is more structured than before. These are real improvements and they matter.

The principal structural break, however, still lies in the bridge between source base and synthesis judgement. The paper now states that 150 publications were retrieved in the Abstract, but the Introduction states that 80 valid papers were finally included after screening. That is exactly the sort of point at which a review article must become more precise, because later synthesis claims depend on the reader being able to trust the route from search to inclusion to judgement. As revised, that route is more visible than before, but it is still not fully secure.

The main secondary weakening lies in contribution control and concluding enlargement. The manuscript is better than before at saying what it covers, and it now signals methodological comparison, multi-dimensional drivers, and future directions more clearly. Yet it still tends to move from review findings into larger claims about ecosystem resilience, water-resource optimisation, ecological security, and even carbon-neutrality support faster than the review body fully earns. The paper is therefore improved, but still somewhat stronger in organised coverage than in tightly bounded synthesis.

The manuscript’s strongest zone remains the middle. The quantification section, especially Table 1 and Table 2, gives the review a recognisable centre, and the new Section 5 does useful work in trying to move beyond serial listing towards interaction and coupling. The revised manuscript therefore no longer reads as a loose thematic sweep in the way the earlier version did. It now has a stronger internal frame.

My overall judgement is that the manuscript has moved materially forward, but it is still not fully settled as a high-confidence review article. It now looks closer to external peer-review readiness than the earlier version, but some important tightening is still needed around review-method precision, contribution control, synthesis discipline, and proportionality of final claims.

A. Title

The revised title is clearly better than the earlier one. It now names the manuscript as “A Review” and narrows the focus to quantitative methods and driving factors, which gives the paper a firmer article identity than the earlier, broader “Research Progress on” formulation. That is a worthwhile improvement because it better matches the actual centre of gravity of the manuscript.

The title is also more aligned with the strongest material in the body. The manuscript’s real centre lies in the comparison of quantification approaches and in the multi-factor account of PUE variation, especially through Table 1, Table 2, and the later driver sections. The new title reflects that centre better than the earlier one.

Even so, the title still stops slightly short of the manuscript’s full shape. The paper does not only review quantitative methods and driving factors. It also contains a substantial conceptual section on the ecological connotation of PUE, a practical section on enhancement approaches, and a future-oriented section on limitations and prospects. The present title is therefore stronger than before, but still somewhat narrower than the manuscript it names.

There is also a subtle contribution issue here. The title tells the reader the review’s topic and angle, but not yet its distinctive synthesis value. That is not always necessary in a review title, but in this case it matters because the manuscript still works hard to establish what it adds beyond organised coverage. A more explicit integrative or comparative signal could still help.

Overall, the title is now serviceable and substantially improved. It is no longer a weakness in the same way it was before. But it is best understood as a corrected title rather than a maximally incisive one.

Actions — A

1. Keep the review identity in the title.

2. Consider whether “integrative review” or “comparative review” would better capture the manuscript’s actual scope.

3. Check that the title and keywords now pull in the same direction.

4. Avoid letting the title become narrower than the real manuscript architecture.

5. Ensure the title’s final wording supports the contribution statement in the Abstract and Introduction.

B. Abstract

The Abstract is improved in one crucial respect. It now includes explicit review-method language, stating that the study systematically retrieved literature from Web of Science and CNKI, applied secondary screening, and extracted key information for integration and discussion. That is a material advance over the earlier version, which asked the reader to trust the review architecture without seeing enough of the route into it.

However, the Abstract also contains the sharpest visible inconsistency in the revised manuscript. It states that 150 publications were retrieved and then screened, whereas the Introduction states that 80 valid papers were finally included. A review article can of course report both retrieval and inclusion counts, but here the relationship between those numbers is not yet expressed cleanly enough in the front matter. That weakens confidence precisely where the review is trying to strengthen it.

The Abstract is clearer than before in explaining what the paper does: it elaborates connotation, compares quantification methods, analyses spatiotemporal differentiation and drivers, summarises enhancement approaches, and proposes future directions. That is good coverage. The problem is that coverage still comes through more strongly than the paper’s narrower, defensible contribution. The manuscript appears to contribute a comparative organisation of methods, a structured integration of driver classes, and a summary of major current limitations. That narrower contribution should be stated more crisply.

The final sentences remain ambitious. They move from the review body towards broad aims involving climate-change response mechanisms, ecosystem resilience, water-resource optimisation, and sustainable ecological construction. Those aims are understandable, but the Abstract still enlarges slightly faster than the review evidence justifies. The tone is more controlled than before, yet still somewhat expansive.

The keywords are also improved in some respects, but they still look more like topical labels than a sharpened signal of review identity. “Precipitation Use Efficiency” and “Quantification Methods” are central. “Ecological Connotation” and “Driving Factors” are understandable. But the set still does not quite capture the comparative and synthesis burden that the paper is trying to assume.

Actions — B

1. Resolve the 150 versus 80 literature-count presentation so the review route reads cleanly.

2. State the manuscript’s narrowest defensible contribution more directly in one sentence.

3. Reduce broad claims about resilience, optimisation, and sustainability unless tied more closely to the review’s demonstrated synthesis.

4. Make sure the Abstract distinguishes retrieval, screening, and inclusion more transparently.

5. Re-check the keyword set for alignment with review identity and comparative synthesis.

C. Introduction

The Introduction is stronger than before because it now contains an explicit literature-search paragraph and a clearer forward frame for the review. That is a real response to the earlier structural criticism, and it improves trust in the manuscript. The paper no longer moves straight from broad topic importance into thematic body without showing at least some review-method scaffolding.

The opening still does useful scene-setting work. It places PUE within climate change, water scarcity, precipitation variability, and ecosystem functioning, and it distinguishes the two recurrent ecological settings in the literature, namely Qinghai-Tibet Plateau systems and dryland ecosystems. That gives the review some geographic and ecological centre of gravity rather than presenting the field as evenly distributed.

The literature-search paragraph is an improvement, but it is still too compressed for the weight later placed on the synthesis. The databases are named, the keywords are given, and screening is mentioned, yet the inclusion and exclusion logic remains thinly specified, and the route from search to final selection to thematic structuring is not yet laid out with full confidence. The reader can now see the bridge, but it is still only partly built.

The final orienting paragraph is also improved, because it now makes the manuscript’s intended structure more explicit and states the kinds of issues to be discussed. Even so, the contribution chain remains somewhat mixed. The paragraph still leans heavily on significance and application language, especially around diagnosis, early warning, water management, and decision support. The review’s distinctive synthesis value is present, but still not stated with full economy.

Overall, the Introduction has moved from a major weakness to a moderate one. It now does more of the work a review introduction should do. But because this is a review manuscript, “more visible” is not yet the same as “fully secured”. The paper still needs a cleaner and more explicit source-base-to-synthesis bridge.

Actions — C

1. Strengthen the screening logic so the route from retrieval to inclusion is more explicit.

2. State the review’s distinct synthesis value more sharply in the final orienting paragraph.

3. Keep the geographic and ecological centre of gravity, but avoid letting it substitute for a formal review rationale.

4. Reduce application-heavy language where it outruns what the review itself directly establishes.

5. Ensure the Introduction and Abstract present the same source-base logic and contribution scale.

D. Materials and methods

For a review manuscript, this remains the most exposed structural zone, even after revision. The revised paper has clearly tried to address the earlier problem by adding a literature-search description in the Introduction and by reporting databases, keywords, screening, and extracted fields. That is a substantive improvement.

But the problem has not fully disappeared, because the method remains embedded as a short front-matter paragraph rather than standing with the clarity of a fully secure review-method account. The manuscript says there were unified inclusion and exclusion criteria, yet these criteria are not actually spelled out with enough specificity for a review carrying strong later synthesis claims. The method is therefore present, but still somewhat under-specified.

The most serious local problem is the mismatch between the 150 publications reported in the Abstract and the 80 valid papers reported in the Introduction. A review article can validly distinguish between retrieved and included records, but the manuscript must make that distinction explicit and stable. At present the reader has to infer too much. That weakens methodological confidence at exactly the point where it should be strongest.

There is also a structural issue in where the method sits. Because the literature-search logic is folded into the Introduction rather than given a more visible review-method identity, the paper still feels slightly intuitive in its later thematic movement. The review may well have been conducted systematically, but its methodology is not yet given enough architectural prominence relative to the interpretive work the paper wants to do.

So this section is improved, but it remains the principal break. The manuscript has moved from “method absent” to “method visible but not fully secured”. For a review article, that distinction matters a great deal.

Actions — D

1. Make retrieval, screening, and final inclusion counts internally consistent and explicitly related.

2. State the inclusion and exclusion criteria in clearer operational terms.

3. Consider giving the review-method account a more visible structural identity than a compressed introductory paragraph.

4. Clarify how the selected papers were grouped into the present thematic architecture.

5. Ensure that later synthesis claims do not outrun what this review-method account can currently carry.

E. Results and synthesis body

The revised manuscript’s strongest zone remains the middle. The connotation section, the quantification-method section, and the driver-analysis section now give the paper a recognisable and reasonably stable body. Table 1 and Table 2 in particular do much of the paper’s organising work, and the revisions have made their function clearer than before.

Table 1 is especially useful because it shows that PUE is not operationalised through one settled formula but through several related formulations involving NPP, GPP, ANPP, NDVI, SAVI, and AGB. That is exactly the kind of organised comparison a review article should provide. The surrounding text is also somewhat better than before at explaining why those differences matter.

Table 2 is also stronger than before because it now provides not only methods and names but also advantages, significance, and application scenarios. That is a real gain. Even so, the review still leans at times towards structured listing rather than decisive comparison. The reader is shown that many methods exist, but is still given less help than ideal in judging which method families are stronger for which inferential purposes.

Section 4 is broad and information-rich, and the new Section 5 does useful integrative work by trying to move beyond single-factor description towards coupling and interaction. That said, the synthesis remains stronger in organisation than in discriminating judgement. The paper often says what studies report, but less often says which patterns are robust, which are context-bound, and which arise partly from differences in method or scale.

So the results-like body is now informative and materially improved. It no longer lacks centre. But it still stops just short of the strongest review standard because synthesis is not yet consistently converted into sharper comparative judgement. In CPR-GF terms, the load-bearing middle is stronger than the edges, but still not fully concentrated.

Actions — E

1. Push the method-comparison sections further from organised listing towards ranked comparative judgement.

2. Indicate more clearly where patterns appear robust and where they remain scale- or context-dependent.

3. Use Table 1 and Table 2 more actively as argumentative platforms, not only as repositories.

4. In Section 5, sharpen the difference between general coupling logic and evidence that remains region-specific.

5. Reduce descriptive repetition where the tables already carry the necessary informational burden.

F. Discussion

The revised manuscript improves markedly here through the addition of Section 5, “Comprehensive Discussion of Driving Factors”. That section is the clearest sign that the authors responded seriously to the earlier criticism that the paper needed firmer interpretive integration rather than continued serial reporting.

Section 5 is useful because it frames PUE as arising from hierarchical interaction rather than from a single dominant factor. The hydrothermal discussion, the attention to topography-vegetation-soil interactions, and the attempt to discuss directed coupling under future climate all help give the paper more interpretive grip than before.

Even so, the Discussion remains somewhat uneven in the relation between evidence and forward reach. Some passages still move quickly from the reviewed literature into rather broad statements about full-chain ecosystem logic, ecological stability, or future quantitative needs. These moves are not wholly unjustified, but they are sometimes expressed with more confidence than the manuscript’s review-method exposure and comparative synthesis fully warrant.

The strongest part of the Discussion is where it stays close to interaction and heterogeneity. The weaker part is where it edges into high-level framing language that sounds more settled than the body has quite shown. In other words, the review is better at identifying the field’s complexity than at deciding the exact strength of some of its own summarising claims.

Overall, this section has improved enough to change the manuscript’s balance. The paper now has a genuine discussion layer rather than a loose future-facing tail. But interpretive restraint still matters here, because this is the part of the paper most likely to outrun what the bridge from source base to synthesis can securely support.

Actions — F

1. Keep Section 5, because it materially improves the manuscript’s centre of gravity.

2. Tighten places where discussion language sounds more settled than the demonstrated synthesis base allows.

3. Distinguish more clearly between robust synthesis, plausible interpretation, and forward-looking proposal.

4. Reduce high-level ecosystem-significance language unless it is directly tied back to reviewed evidence.

5. Make the discussion less cumulative and more evaluative where competing drivers or scales are involved.

G. Conclusion

The revised conclusion is better than the earlier one. It is now more structured and more explicit about the manuscript’s main findings, and the numbered sequence helps stabilise the final section. That is a clear improvement over the earlier more diffuse closing.

The conclusion is strongest where it states that PUE differentiation is jointly driven by four broad factor classes and where it points to shortcomings in multi-scale coupling, interaction analysis, extreme-climate response, and long-term monitoring. Those are plausible synthesis outcomes from the body as revised.

The section is weaker where it continues to widen into large external significance. Phrases about direct support for ecological degradation diagnosis, restoration evaluation, efficient precipitation-resource use, ecosystem resilience, water security, sustainable ecological construction, and carbon peaking and carbon neutrality still enlarge the conclusion beyond the most securely demonstrated scale of the review.

There is also still a contribution issue here. The conclusion now says more clearly what the paper has covered and what it has integrated, but it still does not state quite sharply enough what this review adds that a broad thematic survey would not. The narrowest defensible contribution appears to be a structured comparative synthesis of quantification approaches, interacting drivers, practical enhancement routes, and recurrent research gaps. That narrower wording would serve the conclusion better.

So the conclusion has moved from a serious weakness to a partly corrected one. It now closes the review more recognisably, but it still needs firmer distillation and less enlargement. In CPR-GF terms, the edge is improved but still softer than the middle.

Actions — G

1. Keep the numbered conclusion structure, because it improves clarity.

2. Recast the contribution more narrowly and more explicitly.

3. Remove or soften large downstream claims that the review itself does not directly establish.

4. Distil the strongest evidence-led insights before moving to wider implication.

5. Ensure the final paragraph closes the review rather than reopening a broad agenda.

H. Tables and figures

The tables and figures carry real argumentative weight in this manuscript, and the review should say so more directly. Table 1 and Table 2 are not supplementary conveniences. They are the main platforms through which the paper tries to turn a large, uneven literature into something comparatively intelligible. That is why this section deserves firmer pressure than it received previously. The visual layer is one of the manuscript’s strongest assets, but it is also one of the places where organised presentation risks being mistaken for completed synthesis.

Table 1 is the clearest success in the visual architecture. It gathers multiple PUE formulations, defines variables, indicates computational significance, and gives application scenarios. That allows the reader to see immediately that PUE is not quantified through one settled formula but through several related routes with different emphases and different levels of ecological directness. The review should therefore press the authors to use Table 1 more decisively as an argumentative platform. At present the table is stronger than some of the prose that surrounds it.

Table 2 is improved relative to the earlier manuscript because it now includes advantages, significance, and application scenarios for the method families listed. That is a real gain. But it is still dense, and density itself is not synthesis. The problem is not that the table is too full to exist. The problem is that the paper still does not consistently convert this density into comparative judgement. The review should therefore push harder on the question of which methods are mainly exploratory, which are stronger for threshold detection, which are stronger for contribution partitioning, and which remain interpretively weaker despite technical sophistication.

Figure 2 remains the most exposed visual object in the manuscript. The accompanying text says that it presents a full-chain logic from driving factors through hydrological processes to PUE response and ecological stability, and it links PUE to soil and water conservation, irrigation security, productivity improvement, and broader ecological functions. That is a very large inferential burden for one figure. The figure is useful as a conceptual organiser, but the review should state more sharply that it is schematic and integrative, not demonstrative proof of those broader downstream relationships. Figure 3 is less exposed because it is practical and more modest in what it tries to do.

There are still also small but telling presentation-control issues. The manuscript continues to use forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading remains awkwardly worded as “Provide support for research methodologies and technical approaches”. These are not trivial because they sit exactly where a reviewer checks whether the paper is under editorial control. So this section should push not only on interpretive load, but also on visual and presentational discipline.

Actions — H

Use Table 1 more explicitly as the main comparative platform for formula choice and interpretive consequence.

Rework the prose around Table 2 so that it ranks method families more decisively instead of mainly restating them.

Recast Figure 2 in the text as a schematic integrative model, not as evidence that all downstream stability claims are already secured.

Keep Figure 3 in a modest practical role and avoid giving it explanatory weight beyond applied illustration.

Correct remaining visual-control issues such as “Figure.1”, “Table.1”, “Table.2”, “Figure.2”, and the Section 3.2 heading.

I. Language, units, and style

The manuscript is improved at sentence level relative to the earlier version, but this remains one of the areas where revision is still visible on the page. The more obvious earlier faults have largely been corrected, and the paper now reads as more publication-facing than before. Even so, the prose is still often clause-heavy, densely packed, and more effortful than a review article ideally should be. This matters because a review depends on comparative clarity, and when sentences carry too many linked ideas at once, the synthesis loses sharpness. The Abstract is a clear example, because it compresses review method, scope, driver classes, practical approaches, limitations, future directions, and broad significance into one heavily loaded front-end statement.

The Introduction shows the same tendency. The opening pages contain relevant material, but the prose frequently carries too many ideas in a single syntactic movement. That gives the paper an earnest rather than settled tone. The problem is not basic grammatical failure. The problem is that the writing often does not release or separate ideas clearly enough. In a review article, this can blur the difference between established synthesis, contextual framing, and broader application language. The result is that some passages sound more expansive and more confident than the sentence control fully supports.

There are also still visible local editorial-control problems. The manuscript continues to use forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading remains awkwardly phrased as “Provide support for research methodologies and technical approaches”. These are small matters in themselves, but they are still important because they signal that the manuscript has not yet reached full surface-level polish, especially in sections carrying substantial methodological and interpretive weight.

The manuscript also continues to rely at times on enlarged significance language. Expressions around ecological health diagnosis, land degradation early warning, water-resource optimisation, ecosystem resilience, sustainable ecological construction, and related broad outcomes recur in ways that are not always matched by equally restrained phrasing. This is partly a matter of content and partly a matter of style. The writing sometimes moves into large external significance before the review has fully consolidated its own narrower synthesis. That makes the paper sound broader than it yet needs to be.

Units are not the central weakness here, but presentational consistncy still deserves a final sweep because tables, formulas, and labels are doing so much of the paper’s work. The revised manuscript is substantially better than before, yet it still needs one last language-and-presentation tightening before it will read as fully settled rather than thoroughly revised. The remaining issue is therefore not whether the manuscript is understandable. It is whether it sounds precise, controlled, and editorially complete at every point where it is asking the reader to trust its synthesis.

Actions — I

1. Shorten clause-heavy sentences, especially in the Abstract, Introduction, Discussion, and Conclusion.

2. Correct all residual label and punctuation forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”.

3. Rewrite the Section 3.2 heading into clear academic English.

4. Reduce significance-heavy phrasing where the manuscript moves beyond its most clearly supported synthesis.

5. Do one final consistency sweep across labels, formulas, captions, punctuation, and overall presentation style.

J. References and citations

The reference list is now strong enough that the issue is not currency but evidential positioning. Using the visible years in the revised manuscript, the references span 1998 to 2025, with a median year of 2019. The most frequent visible years are 2020 and 2023, and the recent-literature share remains high at roughly 70% within the ten-year window up to the most recent visible reference year. In simple bibliographic terms, the manuscript is not dated. That is a strength.

The more important question is what kind of literature this is. The Introduction itself states that the field has long been concentrated in two main ecological settings, the Qinghai-Tibet Plateau and dryland ecosystems, and that many studies focus on specific vegetation types such as grasslands and deserts. The reference list reflects exactly that centre of gravity. This is not a mismatch betwen manuscript and bibliography. It is a genuine fit. But the review should make the consequence explicit: when the manuscript speaks in broad ecological language, it is still speaking from a literature base with a clear regional and ecosystem concentration.

That point becomes sharper when one looks at the visible reference sequence. The bibliography includes plateau, alpine-grassland, Inner Mongolia, northern Tibet, Loess Plateau, Heilongjiang, and broader grassland-gradient work, with a strong Chinese and dryland weighting. This does not weaken the manuscript’s relevance. It does, however, limit how confidently the review can move from that body of literature to wider statements about ecosystem health diagnosis, ecological resilience, restoration evaluation, and sustainable ecological construction in a more general sense. The review should therefore tie bibliographic spread more directly to claim scale than it did before.

There is also still a presentation issue. The list is improved, but final-list control is not yet fully settled. Capitalisation across titles remains uneven, regional journals and transliterated titles still need careful standardisation, and the final submission version will need a close style sweep. This is not the main bibliographic problem, but it remains visible enough to matter.

So this section should be made more pointed than before. The references are current and broadly fit for purpose. The real issue is not age or obvious relevance. It is whether the manuscript’s broadest claims are scaled appropriately to the actual centre of gravity of the source base. That is the real bibliographic pressure point.

Actions — J

Keep the current source base, because it is current and thematically coherent.

State more explicitly, in the review and ideally in the manuscript, that the literature base is concentrated in alpine, dryland, grassland, and especially Chinese or plateau-centred contexts.

Tighten broad ecological and practical claims where they appear to generalise beyond that source-base centre of gravity.

Do a final consistency sweep across capitalisation, journal style, and transliterated or region-specific titles.

Re-check that the scale of fnal claims matches the scale of the bibliography actually assembled.

K1. Scientific defensibility

The manuscript is now more defensible than the earlier version because it has reduced some obvious front-end and back-end weaknesses and added a visible review-method paragraph plus an integrative discussion layer. Those changes materially improve the paper’s scientific posture.

However, scientific defensibility is still limited by the source-base-to-synthesis bridge. A review article that wants to make strong integrative claims must show exactly how the literature base was assembled and what kind of synthesis discipline governs its conclusions. Here the method is visible, but still under-specified, and the 150-versus-80 discrepancy weakens confidence at the very point where the manuscript asks for trust.

The review’s middle sections are scientifically useful, especially where they compare formulas, methods, and driver classes. The paper is less secure where it uses that body to justify broader statements about ecological diagnosis, resilience, restoration evaluation, or practical decision support. Those statements are plausible, but some are expressed at a higher level of certainty or reach than the review-method architecture fully secures.

So the scientific defensibility is moderate to good, not weak. The manuscript is not collapsing under its own claims. But it still overstates slightly at the edges, and because this is a review article, that matters. The scientific problem is not fabrication. It is proportionality.

In CPR-GF terms, the manuscript is now scientifically more stable than before, but still not fully stable. The main remaining instability lies in the bridge and in the scale of some closing claims.

Actions — K1

1. Resolve the review-method inconsistency and under-specification first, because this is the main defensibility issue.

2. Keep broad significance claims proportionate to what the review body directly demonstrates.

3. Distinguish more carefully between synthesis outcomes and downstream practical implications.

4. Avoid letting confident tone substitute for methodological security.

5. Strengthen the link between source-base transparency and final review claims.

K2. Structural coherence

The manuscript is now structurally coherent in broad sequence, and that is an important strength. The reader can follow the line of movement from review framing and literature-search description into conceptual clarification, quantification methods, driving factors, practical improvement approaches, future research directions, and conclusion. This is no longer a loose or wandering review. The manuscript has a recognisable path through its material.

The front of the paper is stronger than before, but it is still the least settled part of the structure. The title, Abstract, and Introduction now point more clearly to a review article, and the added search paragraph improves the paper’s opening architecture. The difficulty is that the opening still has to do too much work at once. It establishes significance, introduces the literature base, signals the review route, and begins to announce broad practical relevance. That means the front of the manuscript is improved, but still slightly overburdened.

The middle of the paper is the most coherent part. The sequence from conceptual connotation to quantification methods and then to driver analysis is logical and well aligned with the manuscript’s central subject. The addition of the new discussion section strengthens that coherence further because it gives the review a more recognisable integrative centre rather than leaving the paper as a chain of adjacent thematic blocks. This middle is the part of the manuscript that most clearly justifies the review’s existence.

The coherence weakens somewhat again near the end, though not because the later sections are misplaced. The practical approaches, future directions, and conclusion all follow logically from the earlier sections. The problem is that the scale of the language begins to widen more quickly than the structural sequence itself requires. In other words, the manuscript remains orderly, but the later interpretive reach is slightly broader than the earlier methodological and comparative grounding fully secures. That is not a failure of sequence. It is a softening of structural discipline at the edges.

So the structural judgement here should be stated carefully. The manuscript is no longer weak because its parts do not fit together. Its parts do fit together. The remaining issue is that the opening is still carrying a little too much, the middle is stronger than the edges, and the closing sections widen in scope faster than the review’s most secure structural base fully supports. The paper is therefore coherent in organisation, but not yet equally strong in all parts of its architecture.

Actions - K2

1. Keep the present middle architecture, because the manuscript now has a clear and workable centre.

2. Lighten the opening burden by separating significance, review method, and contribution more cleanly.

3. Preserve the new discussion section, because it improves the structural continuity of the paper.

4. Tighten the later sections so that practical and future-oriented language grows from the review body more proportionately.

5. Aim for a structure in which the opening promise, middle synthesis, and final claim scale feel equally strong rather than middle-strong and edge-softened.

K3. Interpretive restraint

This remains one of the manuscript’s more sensitive zones. The paper has clearly improved, and the new Section 5 helps it interpret the literature in a more integrated way. But the review still tends at times to move from organised synthesis into higher-level implication too readily.

The problem is not that the manuscript says unreasonable things. The problem is that it sometimes says reasonable things at a slightly larger scale than the review’s methodological exposure and comparative discrimination have fully earned. This is especially visible in the Abstract, parts of the Discussion, and the concluding final paragraph.

Interpretive restraint is strongest where the paper stays close to differences among formulas, methods, ecological settings, and interacting driver classes. It is weaker where it moves into language about direct support for diagnosis, restoration evaluation, water security, sustainable ecological construction, and carbon-neutrality goals. Those formulations could be softened or better bounded without weakening the paper’s real contribution.

The future directions section is also ambitious. Some of that ambition is justified, because identifying limitations and prospects is part of a review article’s role. But the section still edges close to becoming a programme statement in places, especially where new technological and interdisciplinary pathways are described with strong normative forward momentum.

So interpretive restraint is improved, but still not complete. The manuscript is not wildly overstated. It is simply not yet fully disciplined at the boundary between what the review shows and what the authors would like the field to do next.

Actions — K3

1. Soften high-level implication language where it outruns the demonstrated synthesis.

2. Keep future directions clearly marked as proposals rather than as evidence-led findings.

3. Distinguish field significance from review-specific contribution more consistently.

4. Trim phrases suggesting direct practical applicability unless the review has clearly established that level of support.

5. Let the manuscript finish on a distilled review judgement rather than a widened agenda.

K4. Evidential spine and overall readiness

This manuscript is now best described as middle-strong with softened edges and a still partly exposed bridge. The opening is improved because review identity and literature-search language are more visible than before, but the bridge from retrieval to inclusion to thematic synthesis remains only partly secured. The middle carries the manuscript well. The ending is more structured, but still enlarges somewhat.

The load-bearing middle is the clearest strength. Sections 2 to 5 now give the paper a coherent thematic and analytical centre, especially through Table 1, Table 2, the driver sections, and the new integrative discussion. This is where the manuscript is most persuasive.

The bridge integrity remains the main problem. The paper now says more about how literature was gathered and screened, but the source-base logic still does not feel fully robust enough for the scale of synthesis later attempted, particularly in light of the front-end count inconsistency. This is why the principal break remains methodological-synthetic rather than merely linguistic.

The closing distillation is improved but not yet fully disciplined. The numbered conclusion gives the paper better form, yet the manuscript still uses its integrated review body to support some broader practical and policy-facing language that exceeds the narrowest defensible contribution. The evidential spine therefore holds, but not yet at maximum tension.

My final readiness judgement is that the manuscript has moved substantially closer to peer-review readiness, but still needs further revision before it is fully secure as a review article. The revisions have been serious and meaningful. The paper is no longer exposed in the same way as the earlier version. But because the principal break remains active, I would still place it in the stronger end of major revision rather than in clean peer-review readiness.

Actions — K4

1. Fix the bridge first: make the review-method route internally consistent and more explicit.

2. Keep the strengthened middle sections, because they now carry the manuscript well.

3. Narrow the final contribution to what the review most securely establishes.

4. Reduce closing enlargement so the edge matches the strength of the middle.

5. After those changes, do one final language and presentation sweep to bring the manuscript into a more settled review form.

Overall recommendation

Major revision, but materially improved and now closer to external peer-review readiness than the earlier version. The manuscript’s trajectory is positive. The remaining work is concentrated rather than diffuse: secure the review-method bridge, tighten the contribution chain, convert organised coverage into slightly sharper synthesis judgement, and restrain the enlarged closing claims.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Comments on the Quality of English Language

See report

Author Response

Reviewer 1:

1.This revised review manuscript is stronger than the earlier version and is no longer exposed in quite the same way at the front and back ends. The title now identifies the paper more clearly as a review, the Introduction now contains an explicit literature-search paragraph, the body has been expanded through a new integrative discussion section, and the Conclusion is more structured than before. These are real improvements and they matter. he principal structural break, however, still lies in the bridge between source base and synthesis judgement. The paper now states that 150 publications were retrieved in the Abstract, but the Introduction states that 80 valid papers were finally included after screening. That is exactly the sort of point at which a review article must become more precise, because later synthesis claims depend on the reader being able to trust the route from search to inclusion to judgement. As revised, that route is more visible than before, but it is still not fully secure. he main secondary weakening lies in contribution control and concluding enlargement. The manuscript is better than before at saying what it covers, and it now signals methodological comparison, multi-dimensional drivers, and future directions more clearly. Yet it still tends to move from review findings into larger claims about ecosystem resilience, water-resource optimisation, ecological security, and even carbon-neutrality support faster than the review body fully earns. The paper is therefore improved, but still somewhat stronger in organised coverage than in tightly bounded synthesis. The manuscript’s strongest zone remains the middle. The quantification section, especially Table 1 and Table 2, gives the review a recognisable centre, and the new Section 5 does useful work in trying to move beyond serial listing towards interaction and coupling. The revised manuscript therefore no longer reads as a loose thematic sweep in the way the earlier version did. It now has a stronger internal frame. My overall judgement is that the manuscript has moved materially forward, but it is still not fully settled as a high-confidence review article. It now looks closer to external peer-review readiness than the earlier version, but some important tightening is still needed around review-method precision, contribution control, synthesis discipline, and proportionality of final claims.

Ans: We sincerely appreciate the reviewer for conducting a comprehensive, rigorous, and highly constructive review of the entire review manuscript. The insightful and professional comments you provided have pointed out the key directions for us to further improve the paper. We fully acknowledge that the overall quality of the manuscript has been significantly enhanced after this round of revisions, but there is still room for optimization in terms of the connection between the literature base and synthetic judgment, the definition of research contributions, and the scope of concluding discussions. Regarding the inconsistency between the 150 retrieved publications mentioned in the Abstract and the 80 finally included papers stated in the Introduction, we have uniformly sorted out and clearly presented this information throughout the manuscript, detailing the complete process from literature retrieval and screening to final inclusion. This further enhances the rigor and credibility of the methodology. Meanwhile, we have streamlined the overly broad statements related to ecosystem stability, water resource optimization, ecological security, and carbon neutrality as much as possible, ensuring that these discussions are highly consistent with the core scope of the review. We have retained and strengthened the core advantages of the middle sections, including quantitative analysis, Table 1, Table 2, and the newly added integrative discussion chapter, reducing simple enumeration and emphasizing the analysis of interactions and coupling mechanisms. Through the aforementioned revisions, the manuscript has achieved further improvements in methodological precision, definition of research contributions, standardization of synthetic analysis, and rationality of conclusions, with a more robust overall structure and rigorous argumentation. We sincerely thank the reviewer again for your careful guidance and valuable comments, which have helped the manuscript continuously move toward meeting high-quality review standards.

2. A. Title

The revised title is clearly better than the earlier one. It now names the manuscript as “A Review” and narrows the focus to quantitative methods and driving factors, which gives the paper a firmer article identity than the earlier, broader “Research Progress on” formulation. That is a worthwhile improvement because it better matches the actual centre of gravity of the manuscript. The title is also more aligned with the strongest material in the body. The manuscript’s real centre lies in the comparison of quantification approaches and in the multi-factor account of PUE variation, especially through Table 1, Table 2, and the later driver sections. The new title reflects that centre better than the earlier one. Even so, the title still stops slightly short of the manuscripts full shape. The paper does not only review quantitative methods and driving factors. It also contains a substantial conceptual section on the ecological connotation of PUE, a practical section on enhancement approaches, and a future-oriented section on limitations and prospects. The present title is therefore stronger than before, but still somewhat narrower than the manuscript it names. There is also a subtle contribution issue here. The title tells the reader the review’s topic and angle, but not yet its distinctive synthesis value. That is not always necessary in a review title, but in this case it matters because the manuscript still works hard to establish what it adds beyond organised coverage. A more explicit integrative or comparative signal could still help.

Overall, the title is now serviceable and substantially improved. It is no longer a weakness in the same way it was before. But it is best understood as a corrected title rather than a maximally incisive one. Actions-A:1. Keep the review identity in the title.

2. Consider whether “integrative review” or “comparative review” would better capture the manuscript’s actual scope. 3. Check that the title and keywords now pull in the same direction. 4. Avoid letting the title become narrower than the real manuscript architecture. 5. Ensure the title’s final wording supports the contribution statement in the Abstract and Introduction.

Ans: We sincerely appreciate the reviewer for the professional and detailed comments on the title. We fully agree that the revised title has been significantly improved—it clearly identifies the manuscript as “A Review” and focuses on quantitative methods and driving factors, which is highly consistent with the core content and central focus of the manuscript. At the same time, we also recognize that the current title still has room for optimization: it fails to fully cover the entire scope of the manuscript, including the ecological connotation of PUE, enhancement approaches, and future prospects, and does not fully reflect the unique synthetic value of the research. Based on this, in the subsequent revision, we will retain the “review” identity in the title, appropriately adjust the title scope to fully cover all core content of the manuscript, and avoid the title being narrower than the actual research framework. We will also consider adding terms such as “integrative” or “comparative” to clearly reflect the synthetic and comparative characteristics of the study, so that the title can not only reflect the core scope of the review but also highlight the unique value of this research. In addition, we will check and align the consistency between the title and keywords, ensuring that they move in the same direction, and that the title can support the expression of research contributions in the abstract and introduction. We sincerely thank the reviewer for the valuable guidance, which helps us further improve the title and the overall quality of the manuscript (Lines 2-4).

3. B. Abstract

The Abstract is improved in one crucial respect. It now includes explicit review-method language, stating that the study systematically retrieved literature from Web of Science and CNKI, applied secondary screening, and extracted key information for integration and discussion. That is a material advance over the earlier version, which asked the reader to trust the review architecture without seeing enough of the route into it. However, the Abstract also contains the sharpest visible inconsistency in the revised manuscript. It states that 150 publications were retrieved and then screened, whereas the Introduction states that 80 valid papers were finally included. A review article can of course report both retrieval and inclusion counts, but here the relationship between those numbers is not yet expressed cleanly enough in the front matter. That weakens confidence precisely where the review is trying to strengthen it. The Abstract is clearer than before in explaining what the paper does: it elaborates connotation, compares quantification methods, analyses spatiotemporal differentiation and drivers, summarises enhancement approaches, and proposes future directions. That is good coverage. The problem is that coverage still comes through more strongly than the paper’s narrower, defensible contribution. The manuscript appears to contribute a comparative organisation of methods, a structured integration of driver classes, and a summary of major current limitations. That narrower contribution should be stated more crisply. The final sentences remain ambitious. They move from the review body towards broad aims involving climate-change response mechanisms, ecosystem resilience, water-resource optimisation, and sustainable ecological construction. Those aims are understandable, but the Abstract still enlarges slightly faster than the review evidence justifies. The tone is more controlled than before, yet still somewhat expansive.

The keywords are also improved in some respects, but they still look more like topical labels than a sharpened signal of review identity. “Precipitation Use Efficiency” and “Quantification Methods” are central. “Ecological Connotation” and “Driving Factors” are understandable. But the set still does not quite capture the comparative and synthesis burden that the paper is trying to assume. Actions-B:1. Resolve the 150 versus 80 literature-count presentation so the review route reads cleanly. 2. State the manuscript’s narrowest defensible contribution more directly in one sentence. 3. Reduce broad claims about resilience, optimisation, and sustainability unless tied more closely to the review’s demonstrated synthesis. 4. Make sure the Abstract distinguishes retrieval, screening, and inclusion more transparently. 5. Re-check the keyword set for alignment with review identity and comparative synthesis.

Ans: We sincerely appreciate the reviewer’s professional, detailed and insightful comments on the abstract and keywords. We fully agree with the reviewer’s observations that the abstract has been improved in terms of methodological transparency but still has room for optimization in terms of literature count consistency, contribution clarification, and scope control, and that the keywords need to be more closely aligned with the review’s comparative and synthetic characteristics. In response to the review comments, we will focus on the following improvements: First, we will clarify the relationship between the 150 retrieved publications and 80 finally included papers, clearly elaborate the complete process of literature retrieval, screening and inclusion, and resolve the inconsistency in the presentation of literature counts to enhance the transparency and credibility of the research method. Second, we will refine the statement of the manuscript’s core contribution, using a concise sentence to clearly present the unique value of this review—including the comparative analysis of PUE quantification methods, the integrated analysis of driving factors, and the summary of research limitations—to make the contribution more direct and clear. Third, we will moderate the overly broad statements in the final part of the abstract, removing or softening claims about climate-change response mechanisms, ecosystem resilience, water-resource optimization and sustainable construction that are not fully supported by the review’s evidence, ensuring the content is consistent with the scope of the review. Fourth, we will further clarify the distinction between literature retrieval, screening and inclusion in the abstract, providing sufficient details to strengthen reader trust. Fifth, we will re-examine and optimize the keyword set, retaining core terms such as “Precipitation Use Efficiency” and “Quantification Methods”, adding terms that reflect the comparative and synthetic nature of the study, and ensuring the keywords are fully aligned with the review’s identity and research focus. We will strictly implement the above revisions to improve the accuracy, rigor and relevance of the abstract and keywords, and sincerely thank the reviewer for the valuable guidance, which helps us further enhance the quality of the manuscript (Lines 18-41).

4. C. Introduction

The Introduction is stronger than before because it now contains an explicit literature-search paragraph and a clearer forward frame for the review. That is a real response to the earlier structural criticism, and it improves trust in the manuscript. The paper no longer moves straight from broad topic importance into thematic body without showing at least some review-method scaffolding. The opening still does useful scene-setting work. It places PUE within climate change, water scarcity, precipitation variability, and ecosystem functioning, and it distinguishes the two recurrent ecological settings in the literature, namely Qinghai-Tibet Plateau systems and dryland ecosystems. That gives the review some geographic and ecological centre of gravity rather than presenting the field as evenly distributed. The literature-search paragraph is an improvement, but it is still too compressed for the weight later placed on the synthesis. The databases are named, the keywords are given, and screening is mentioned, yet the inclusion and exclusion logic remains thinly specified, and the route from search to final selection to thematic structuring is not yet laid out with full confidence. The reader can now see the bridge, but it is still only partly built. The final orienting paragraph is also improved, because it now makes the manuscript’s intended structure more explicit and states the kinds of issues to be discussed. Even so, the contribution chain remains somewhat mixed. The paragraph still leans heavily on significance and application language, especially around diagnosis, early warning, water management, and decision support. The review’s distinctive synthesis value is present, but still not stated with full economy.

Overall, the Introduction has moved from a major weakness to a moderate one. It now does more of the work a review introduction should do. But because this is a review manuscript, “more visible” is not yet the same as “fully secured”. The paper still needs a cleaner and more explicit source-base-to-synthesis bridge. Actions-C: 1. Strengthen the screening logic so the route from retrieval to inclusion is more explicit. 2. State the review’s distinct synthesis value more sharply in the final orienting paragraph. 3. Keep the geographic and ecological centre of gravity, but avoid letting it substitute for a formal review rationale. 4. Reduce application-heavy language where it outruns what the review itself directly establishes. 5. Ensure the Introduction and Abstract present the same source-base logic and contribution scale.

Ans: We sincerely appreciate the reviewer’s professional and in-depth comments on the Introduction section. We fully agree with the evaluation that the Introduction has been improved with explicit literature-search content and a clearer framework, while also acknowledging the remaining gaps in the literature retrieval-screening logic and contribution expression. In this revision, we will focus on addressing the key issues pointed out in the review: First, we will strengthen the screening logic by adding specific inclusion and exclusion criteria, clearly elaborating the complete process from literature retrieval (150 publications) to final inclusion (80 valid papers), and clarifying the logical link between retrieval, screening and thematic structuring, so as to build a more robust “source base-synthesis” bridge and enhance the credibility of the review. Second, we will retain the clear geographic and ecological focus of the Introduction, including the emphasis on Qinghai-Tibet Plateau and dryland ecosystems, while avoiding substituting this focus for a formal review rationale. Third, we will reduce application-heavy language that exceeds the support of the review’s evidence, especially statements related to diagnosis, early warning, water management and decision support that are not directly supported by the reviewed literature. Fourth, we will refine the final orienting paragraph of the Introduction, clearly stating the review’s distinct synthetic value in a concise way, rather than over-relying on significance and application language. Finally, we will ensure that the source-base logic, contribution scale and core content of the Introduction are fully consistent with the Abstract, avoiding any contradictions or inconsistencies. We will strictly follow the revision suggestions to optimize the Introduction, enhance its rigor and completeness, and further narrow the gap between the current version and the standard of a high-quality review. We sincerely thank the reviewer for the valuable guidance, which helps us better improve the manuscript and meet the requirements of academic norms (Lines 44-117).

5. D. Materials and methods

For a review manuscript, this remains the most exposed structural zone, even after revision. The revised paper has clearly tried to address the earlier problem by adding a literature-search description in the Introduction and by reporting databases, keywords, screening, and extracted fields. That is a substantive improvement. But the problem has not fully disappeared, because the method remains embedded as a short front-matter paragraph rather than standing with the clarity of a fully secure review-method account. The manuscript says there were unified inclusion and exclusion criteria, yet these criteria are not actually spelled out with enough specificity for a review carrying strong later synthesis claims. The method is therefore present, but still somewhat under-specified. The most serious local problem is the mismatch between the 150 publications reported in the Abstract and the 80 valid papers reported in the Introduction. A review article can validly distinguish between retrieved and included records, but the manuscript must make that distinction explicit and stable. At present the reader has to infer too much. That weakens methodological confidence at exactly the point where it should be strongest. There is also a structural issue in where the method sits. Because the literature-search logic is folded into the Introduction rather than given a more visible review-method identity, the paper still feels slightly intuitive in its later thematic movement. The review may well have been conducted systematically, but its methodology is not yet given enough architectural prominence relative to the interpretive work the paper wants to do. So this section is improved, but it remains the principal break. The manuscript has moved from “method absent” to “method visible but not fully secured”. For a review article, that distinction matters a great deal. Actions -D: 1. Make retrieval, screening, and final inclusion counts internally consistent and explicitly related. 2. State the inclusion and exclusion criteria in clearer operational terms. 3. Consider giving the review-method account a more visible structural identity than a compressed introductory paragraph. 4. Clarify how the selected papers were grouped into the present thematic architecture. 5. Ensure that later synthesis claims do not outrun what this review-method account can currently carry.

Ans: We sincerely appreciate the reviewer’s professional and insightful comments on the Materials and Methods section. We fully agree with the evaluation that this section, while improved, still has room for optimization to enhance its rigor and clarity, which is crucial for the overall credibility of the review. In response to the comments, we will make targeted revisions to address the key issues: First, we will clarify and align the counts of retrieved and included papers, explicitly stating the relationship between the 150 retrieved publications and 80 valid included papers to eliminate ambiguity and avoid reader confusion. Second, we will supplement specific, operational inclusion and exclusion criteria (e.g., relevance to PUE research, completeness of data, and reasonable publication time frame) to make the screening process more transparent and rigorous. Third, we will separate the review method content from the Introduction and establish an independent “Review Methodology” section to give it more structural prominence, rather than embedding it as a compressed paragraph. Fourth, we will clearly explain the grouping logic of the 80 included papers, elaborating on how they are categorized based on research themes and method types to support the thematic architecture of the review. Finally, we will ensure that all synthetic claims are strictly based on the reviewed literature and the established review method, avoiding overreach beyond the supporting evidence. We will earnestly implement all the above revisions to strengthen the methodological foundation of the manuscript, ensuring that the Materials and Methods section is sufficiently detailed, consistent, and robust to support the subsequent synthesis and analysis (Lines 119-145).

6. E. Results and synthesis body

The revised manuscript’s strongest zone remains the middle. The connotation section, the quantification-method section, and the driver-analysis section now give the paper a recognisable and reasonably stable body. Table 1 and Table 2 in particular do much of the paper’s organising work, and the revisions have made their function clearer than before. Table 1 is especially useful because it shows that PUE is not operationalized through one settled formula but through several related formulations involving NPP, GPP, ANPP, NDVI, SAVI, and AGB. That is exactly the kind of organised comparison a review article should provide. The surrounding text is also somewhat better than before at explaining why those differences matter. Table 2 is also stronger than before because it now provides not only methods and names but also advantages, significance, and application scenarios. That is a real gain. Even so, the review still leans at times towards structured listing rather than decisive comparison. The reader is shown that many methods exist, but is still given less help than ideal in judging which method families are stronger for which inferential purposes. Section 4 is broad and information-rich, and the new Section 5 does useful integrative work by trying to move beyond single-factor description towards coupling and interaction. That said, the synthesis remains stronger in organisation than in discriminating judgement. The paper often says what studies report, but less often says which patterns are robust, which are context-bound, and which arise partly from differences in method or scale. So the results-like body is now informative and materially improved. It no longer lacks centre. But it still stops just short of the strongest review standard because synthesis is not yet consistently converted into sharper comparative judgement. In CPR-GF terms, the load-bearing middle is stronger than the edges, but still not fully concentrated. Actions-E: 1. Push the method-comparison sections further from organised listing towards ranked comparative judgement. 2. Indicate more clearly where patterns appear robust and where they remain scale- or context-dependent. 3. Use Table 1 and Table 2 more actively as argumentative platforms, not only as repositories. 4. In Section 5, sharpen the difference between general coupling logic and evidence that remains region-specific. 5. Reduce descriptive repetition where the tables already carry the necessary informational burden.

Ans: We sincerely appreciate the reviewer for the detailed, professional, and highly constructive comments on the results and synthesis section. These suggestions have provided important guidance for us to further optimize the argument quality and strengthen the core content of the manuscript. In this revision, we have further emphasized the core argumentative role of Table 1 and Table 2, treating them as important carriers supporting the overall analysis rather than simple information lists. We have also further elaborated on the importance and prominent role of the table information in the main text, giving full play to their core function of integrating literature and assisting argumentation. In Section 5 (now Section 6 in the revised manuscript), we have further clarified the boundary between the theoretical framework of coupling logic and region-specific empirical evidence, making the argument logic clearer and the boundary more distinct. It should be noted that, limited by the content of the authoritative literature included in this review, further refined classification, in-depth comparison for Table 2, as well as more detailed deduction and demonstration for the newly added Section 5, are not feasible. Nevertheless, we have systematically sorted out the research application scenarios of various methods in Table 2, and optimized the comprehensive analysis content to the greatest extent within the support of existing literature, ensuring the rigor and completeness of the argumentation. With these adjustments, the integrative analysis and comparative judgment in the middle part of the manuscript have become more distinct, and the concentration of argumentation has been significantly improved. We sincerely thank the reviewer again for the valuable guidance and insights (Line 300, Line 370, Lines 275-276, Lines 303-368 and Lines and Lines 608-715)

7. F. Discussion

The revised manuscript improves markedly here through the addition of Section 5, “Comprehensive Discussion of Driving Factors”. That section is the clearest sign that the authors responded seriously to the earlier criticism that the paper needed firmer interpretive integration rather than continued serial reporting. Section 5 is useful because it frames PUE as arising from hierarchical interaction rather than from a single dominant factor. The hydrothermal discussion, the attention to topography-vegetation-soil interactions, and the attempt to discuss directed coupling under future climate all help give the paper more interpretive grip than before. Even so, the Discussion remains somewhat uneven in the relation between evidence and forward reach. Some passages still move quickly from the reviewed literature into rather broad statements about full-chain ecosystem logic, ecological stability, or future quantitative needs. These moves are not wholly unjustified, but they are sometimes expressed with more confidence than the manuscript’s review-method exposure and comparative synthesis fully warrant. The strongest part of the Discussion is where it stays close to interaction and heterogeneity. The weaker part is where it edges into high-level framing language that sounds more settled than the body has quite shown. In other words, the review is better at identifying the field’s complexity than at deciding the exact strength of some of its own summarising claims. Overall, this section has improved enough to change the manuscript’s balance. The paper now has a genuine discussion layer rather than a loose future-facing tail. But interpretive restraint still matters here, because this is the part of the paper most likely to outrun what the bridge from source base to synthesis can securely support. Actions-F: 1. Keep Section 5, because it materially improves the manuscript’s centre of gravity. 2. Tighten places where discussion language sounds more settled than the demonstrated synthesis base allows. 3. Distinguish more clearly between robust synthesis, plausible interpretation, and forward-looking proposal.4. Reduce high-level ecosystem-significance language unless it is directly tied back to reviewed evidence. 5. Make the discussion less cumulative and more evaluative where competing drivers or scales are involved.

Ans: We sincerely appreciate the reviewer for the detailed, professional, and highly constructive comments on the discussion section. We fully agree that the newly added Section 5 (now Section 6 in the revised manuscript) on the comprehensive discussion of driving factors has significantly improved the integration of the manuscript, and we have carefully adopted the suggestions regarding the scope of discussion and interpretive restraint. In this revision, we have retained the core content of Section 5 (now Section 6 in the revised manuscript), continuing to highlight its advantages in integrative analysis of hierarchical interactions, hydrothermal conditions, and topography-vegetation-soil coupling. Meanwhile, we have tightened and weakened some overly affirmative macro-ecological statements that exceed direct support from the literature. It should be noted that, limited by the results of existing research literature, we are temporarily unable to more clearly distinguish between robust synthetic conclusions, plausible interpretations, and forward-looking proposals in the text. To adhere to the principle of scientificity and avoid violating the empirical basis of the literature by forcing revisions, we have not made excessive adjustments to this part. However, we have streamlined high-level ecological significance statements that are weakly associated with the review evidence and reduced simple descriptive accumulation, maximizing the rigor of the discussion. With these adjustments, the argumentation in the discussion section has become more restrained and rigorous, and the intensity of the discussion is highly consistent with the literature basis of the review. We sincerely thank the reviewer again for the valuable guidance and insights (Lines 608-715).

9. G. Conclusion

The revised conclusion is better than the earlier one. It is now more structured and more explicit about the manuscript’s main findings, and the numbered sequence helps stabilise the final section. That is a clear improvement over the earlier more diffuse closing. The conclusion is strongest where it states that PUE differentiation is jointly driven by four broad factor classes and where it points to shortcomings in multi-scale coupling, interaction analysis, extreme-climate response, and long-term monitoring. Those are plausible synthesis outcomes from the body as revised. The section is weaker where it continues to widen into large external significance. Phrases about direct support for ecological degradation diagnosis, restoration evaluation, efficient precipitation-resource use, ecosystem resilience, water security, sustainable ecological construction, and carbon peaking and carbon neutrality still enlarge the conclusion beyond the most securely demonstrated scale of the review. There is also still a contribution issue here. The conclusion now says more clearly what the paper has covered and what it has integrated, but it still does not state quite sharply enough what this review adds that a broad thematic survey would not. The narrowest defensible contribution appears to be a structured comparative synthesis of quantification approaches, interacting drivers, practical enhancement routes, and recurrent research gaps. That narrower wording would serve the conclusion better. So the conclusion has moved from a serious weakness to a partly corrected one. It now closes the review more recognisably, but it still needs firmer distillation and less enlargement. In CPR-GF terms, the edge is improved but still softer than the middle. Actions-G: 1. Keep the numbered conclusion structure, because it improves clarity. 2. Recast the contribution more narrowly and more explicitly. 3. Remove or soften large downstream claims that there view itself does not directly establish. 4. Distil the strongest evidence-led insights before moving to wider implication. 5. Ensure the final paragraph closes the review rather than reopening a broad agenda.

Ans: We sincerely appreciate the reviewer for the detailed and professional comments on the conclusion section. Following your suggestions, we have retained the numbered structure to maintain clarity and organization. We have further distilled the core insights based on the strongest evidence from the review before extending to broader implications, and revised the statement of contribution to be narrower and more explicit, highlighting the unique value of this review beyond a general thematic survey. We have removed or moderated overly broad claims concerning ecological degradation diagnosis, ecosystem resilience, water security, sustainable construction, carbon peaking and neutrality that are not directly validated by the review content. The final paragraph has been adjusted to properly close the review instead of reopening an overly broad agenda. These revisions have greatly improved the rigor and focus of the conclusion, ensuring its claims are well proportioned to the evidence and the distinctive contribution is clearly emphasized. We are truly grateful for the reviewer’s valuable guidance (Lines 888-914).

10. H. Tables and figures

The tables and figures carry real argumentative weight in this manuscript, and the review should say so more directly. Table 1 and Table 2 are not supplementary conveniences. They are the main platforms through which the paper tries to turn a large, uneven literature into something comparatively intelligible. That is why this section deserves firmer pressure than it received previously. The visual layer is one of the manuscript’s strongest assets, but it is also one of the places where organised presentation risks being mistaken for completed synthesis. Table 1 is the clearest success in the visual architecture. It gathers multiple PUE formulations, defines variables, indicates computational significance, and gives application scenarios. That allows the reader to see immediately that PUE is not quantified through one settled formula but through several related routes with different emphases and different levels of ecological directness. The review should therefore press the authors to use Table 1 more decisively as an argumentative platform. At present the table is stronger than some of the prose that surrounds it. Table 2 is improved relative to the earlier manuscript because it now includes advantages, significance, and application scenarios for the method families listed. That is a real gain. But it is still dense, and density itself is not synthesis. The problem is not that the table is too full to exist. The problem is that the paper still does not consistently convert this density into comparative judgement. The review should therefore push harder on the question of which methods are mainly exploratory, which are stronger for threshold detection, which are stronger for contribution partitioning, and which remain interpretively weaker despite technical sophistication. Figure 2 remains the most exposed visual object in the manuscript. The accompanying text says that it presents a full-chain logic from driving factors through hydrological processes to PUE response and ecological stability, and it links PUE to soil and water conservation, irrigation security, productivity improvement, and broader ecological functions. That is a very large inferential burden for one figure. The figure is useful as a conceptual organiser, but the review should state more sharply that it is schematic and integrative, not demonstrative proof of those broader downstream relationships. Figure 3 is less exposed because it is practical and more modest in what it tries to do. There are still also small but telling presentation-control issues. The manuscript continues to use forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading remains awkwardly worded as “Provide support for research methodologies and technical approaches”. These are not trivial because they sit exactly where a reviewer checks whether the paper is under editorial control. So this section should push not only on interpretive load, but also on visual and presentational discipline. Actions-H: Use Table 1 more explicitly as the main comparative platform for formula choice and interpretive consequence. Rework the prose around Table 2 so that it ranks method families more decisively instead of mainly restating them. Recast Figure 2 in the text as a schematic integrative model, not as evidence that all downstream stability claims are already secured. Keep Figure 3 in a modest practical role and avoid giving it explanatory weight beyond applied illustration. Correct remaining visual-control issues such as “Figure.1”, “Table.1”, “Table.2”, “Figure.2”, and the Section 3.2 heading.

Ans: We sincerely appreciate the reviewer for the detailed and professional comments on the figures, tables, discussion scale, and formatting of this manuscript. These valuable suggestions have provided important guidance for further improving the rigor and standardization of the paper. We fully agree with the directions for revision proposed by the reviewer and have carefully optimized the manuscript accordingly. In the revision, we have emphasized the core argumentative role of the tables and figures, clarifying that Table 1 and Table 2 are not supplementary materials but key carriers that transform extensive literature into comparable knowledge, representing one of the strengths of this study. We have also adjusted the narrative to avoid misunderstanding that the systematic presentation constitutes a full comprehensive analysis. For Table 1, we have further strengthened its function as a core basis for selecting and interpreting calculation formulas, and improved the supporting textual description to match the high quality of the table. Regarding Table 2, although it has been greatly improved compared with the original version, further classification and evaluation of methods (such as exploratory methods, threshold identification methods, contribution partitioning methods, etc.) is not feasible, because the authoritative literature included in this review does not provide such systematic categorization or evaluation. To maintain academic rigor, we have refined the presentation as much as possible within the support of existing literature to avoid simple enumeration. For Figure 2, we have explicitly stated in the text that it is a schematic integrated model for logical framework illustration, rather than empirical evidence for ecological stability conclusions, so as to reduce its excessive argumentative burden. Figure 3 remains focused on practical applications with an appropriate scale, and we have maintained its illustrative role without overinterpreting its significance. In addition, we have corrected all nonstandard formatting issues, including figure and table labels and the awkward expression of the section title, to enhance the overall standardization of the manuscript. We are truly grateful for the reviewer’s valuable comments and careful guidance (Lines 275-276, Line 300, Lines 303-368, Line 370 and Lines 392-415).

11. I. Language, units, and style

The manuscript is improved at sentence level relative to the earlier version, but this remains one of the areas where revision is still visible on the page. The more obvious earlier faults have largely been corrected, and the paper now reads as more publication-facing than before. Even so, the prose is still often clause-heavy, densely packed, and more effortful than a review article ideally should be. This matters because a review depends on comparative clarity, and when sentences carry too many linked ideas at once, the synthesis loses sharpness. The Abstract is a clear example, because it compresses review method, scope, driver classes, practical approaches, limitations, future directions, and broad significance into one heavily loaded front-end statement. he Introduction shows the same tendency. The opening pages contain relevant material, but the prose frequently carries too many ideas in a single syntactic movement. That gives the paper an earnest rather than settled tone. The problem is not basic grammatical failure. The problem is that the writing often does not release or separate ideas clearly enough. In a review article, this can blur the difference between established synthesis, contextual framing, and broader application language. The result is that some passages sound more expansive and more confident than the sentence control fully supports. here are also still visible local editorial-control problems. The manuscript continues to use forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading remains awkwardly phrased as “Provide support for research methodologies and technical approaches”. These are small matters in themselves, but they are still important because they signal that the manuscript has not yet reached full surface-level polish, especially in sections carrying substantial methodological and interpretive weight. he manuscript also continues to rely at times on enlarged significance language. Expressions around ecological health diagnosis, land degradation early warning, water-resource optimisation, ecosystem resilience, sustainable ecological construction, and related broad outcomes recur in ways that are not always matched by equally restrained phrasing. This is partly a matter of content and partly a matter of style. The writing sometimes moves into large external significance before the review has fully consolidated its own narrower synthesis. That makes the paper sound broader than it yet needs to be. nits are not the central weakness here, but presentational consistncy still deserves a final sweep because tables, formulas, and labels are doing so much of the paper’s work. The revised manuscript is substantially better than before, yet it still needs one last language-and-presentation tightening before it will read as fully settled rather than thoroughly revised. The remaining issue is therefore not whether the manuscript is understandable. It is whether it sounds precise, controlled, and editorially complete at every point where it is asking the reader to trust its synthesis. Actions-I: 1. Shorten clause-heavy sentences, especially in the Abstract, Introduction, Discussion, and Conclusion. 2. Correct all residual label and punctuation forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”. 3. Rewrite the Section 3.2 heading into clear academic English. 4. Reduce significance-heavy phrasing where the manuscript moves beyond its most clearly supported synthesis. 5. Do one final consistency sweep across labels, formulas, captions, punctuation, and overall presentation style.

Ans: We sincerely appreciate the reviewer for the detailed and professional comments on the language, units, formatting, and writing style of the manuscript. These valuable suggestions have provided crucial guidance for further improving the clarity, academic standardization, and rigor of the paper. We fully agree with the issues identified by the reviewer, including overly clause‑heavy sentences, nonstandard label formatting, awkward section headings, and occasionally overextended significance statements, and have carefully revised the manuscript in full accordance with the proposed actions. Regarding linguistic expression, we have systematically revised the Abstract, Introduction, Discussion, and Conclusion by shortening and splitting long, dense sentences to separate ideas more clearly, thus enhancing readability and sharpening the synthesis. For formatting consistency, all nonstandard labels such as “Figure.1” and “Table.1” have been corrected, and the awkward heading of Section 3.2 has been rewritten into concise, natural academic English. We have also reduced overly broad and significance‑heavy expressions related to ecological diagnosis, early warning, ecosystem resilience, and sustainable construction to ensure claims remain proportionate to the supported synthesis. Finally, we have conducted a thorough final check of units, formulas, captions, punctuation, and presentation style to achieve full consistency across the manuscript. These revisions have greatly refined the precision, control, and editorial completeness of the writing, strengthening the reliability of the review’s synthesis. We are truly grateful for the reviewer’s careful guidance and valuable comments.

12. J. References and citations

The reference list is now strong enough that the issue is not currency but evidential positioning. Using the visible years in the revised manuscript, the references span 1998 to 2025, with a median year of 2019. The most frequent visible years are 2020 and 2023, and the recent-literature share remains high at roughly 70% within the ten-year window up to the most recent visible reference year. In simple bibliographic terms, the manuscript is not dated. That is a strength. The more important question is what kind of literature this is. The Introduction itself states that the field has long been concentrated in two main ecological settings, the Qinghai-Tibet Plateau and dryland ecosystems, and that many studies focus on specific vegetation types such as grasslands and deserts. The reference list reflects exactly that centre of gravity. This is not a mismatch betwen manuscript and bibliography. It is a genuine fit. But the review should make the consequence explicit: when the manuscript speaks in broad ecological language, it is still speaking from a literature base with a clear regional and ecosystem concentration. That point becomes sharper when one looks at the visible reference sequence. The bibliography includes plateau, alpine-grassland, Inner Mongolia, northern Tibet, Loess Plateau, Heilongjiang, and broader grassland-gradient work, with a strong Chinese and dryland weighting. This does not weaken the manuscript’s relevance. It does, however, limit how confidently the review can move from that body of literature to wider statements about ecosystem health diagnosis, ecological resilience, restoration evaluation, and sustainable ecological construction in a more general sense. The review should therefore tie bibliographic spread more directly to claim scale than it did before. There is also still a presentation issue. The list is improved, but final-list control is not yet fully settled. Capitalisation across titles remains uneven, regional journals and transliterated titles still need careful standardisation, and the final submission version will need a close style sweep. This is not the main bibliographic problem, but it remains visible enough to matter. So this section should be made more pointed than before. The references are current and broadly fit for purpose. The real issue is not age or obvious relevance. It is whether the manuscript’s broadest claims are scaled appropriately to the actual centre of gravity of the source base. That is the real bibliographic pressure point. Actions-J: Keep the current source base, because it is current and thematically coherent. State more explicitly, in the review and ideally in the manuscript, that the literature base is concentrated in alpine, dryland, grassland, and especially Chinese or plateau-centred contexts. Tighten broad ecological and practical claims where they appear to generalise beyond that source-base centre of gravity. Do a final consistency sweep across capitalisation, journal style, and transliterated or region-specific titles. Re-check that the scale of final claims matches the scale of the bibliography actually assembled.

Ans: We sincerely appreciate the reviewer for the professional and detailed comments on the references and citations of this manuscript. We fully agree with the reviewer’s evaluation of the literature timeliness, regional concentration, and the matching between claim scale and evidence base, and have revised the manuscript accordingly. The references in this paper span from 1998 to 2025, with approximately 70% published in the recent decade, showing strong up-to-dateness and thematic coherence. Therefore, we have retained the current reference base. Meanwhile, we have explicitly stated in the manuscript that the literature is mainly concentrated in alpine, dryland, and grassland ecosystems, particularly studies focusing on Chinese plateau and arid regions, to help readers clearly understand the scope and foundation of this review. We have also tightened overly broad ecological and practical statements that extend beyond the focus of the source base, ensuring that all conclusions are appropriately scaled to the assembled bibliography. In addition, we have conducted a final consistency check on reference formatting, including capitalization, journal styles, and transliterated or region-specific titles, to achieve uniform presentation. These revisions have better aligned the scale of conclusions with the literature evidence and improved the overall standardization of the manuscript. We are truly grateful for the reviewer’s valuable suggestions and careful guidance (Lines 64-69 and Lines 932-1032).

13. K1. Scientific defensibility

The manuscript is now more defensible than the earlier version because it has reduced some obvious front-end and back-end weaknesses and added a visible review-method paragraph plus an integrative discussion layer. Those changes materially improve the paper’s scientific posture. However, scientific defensibility is still limited by the source-base-to-synthesis bridge. A review article that wants to make strong integrative claims must show exactly how the literature base was assembled and what kind of synthesis discipline governs its conclusions. Here the method is visible, but still under-specified, and the 150-versus-80 discrepancy weakens confidence at the very point where the manuscript asks for trust. The review’s middle sections are scientifically useful, especially where they compare formulas, methods, and driver classes. The paper is less secure where it uses that body to justify broader statements about ecological diagnosis, resilience, restoration evaluation, or practical decision support. Those statements are plausible, but some are expressed at a higher level of certainty or reach than the review-method architecture fully secures. So the scientific defensibility is moderate to good, not weak. The manuscript is not collapsing under its own claims. But it still overstates slightly at the edges, and because this is a review article, that matters. The scientific problem is not fabrication. It is proportionality. In CPR-GF terms, the manuscript is now scientifically more stable than before, but still not fully stable. The main remaining instability lies in the bridge and in the scale of some closing claims. Actions-K1: 1. Resolve the review-method inconsistency and under-specification first, because this is the main defensibility issue. 2. Keep broad significance claims proportionate to what the review body directly demonstrates. 3. Distinguish more carefully between synthesis outcomes and downstream practical implications. 4. Avoid letting confident tone substitute for methodological security. 5. Strengthen the link between source-base transparency and final review claims.

Ans: We sincerely appreciate the reviewer for the profound and professional comments on the scientific defensibility and rational argumentation of this manuscript. These suggestions are crucial for improving the scientific rigor and credibility of the review. We fully agree with the issues pointed out by the reviewer, including the underspecified review methodology, inconsistent literature numbers, and somewhat overstated broad claims, and have carried out comprehensive revisions accordingly. First, we have clarified and unified the relationship between the 150 retrieved publications and the 80 finally included papers in the Abstract and Introduction, and further elaborated the complete process of literature search, screening, inclusion, and exclusion to enhance the transparency and standardization of the review methodology, laying a more solid scientific foundation. Meanwhile, we have strictly adjusted the scale of conclusions, moderating and reducing overly broad statements beyond direct support from the reviewed literature, to ensure that the research implications match the core content of the review. We have also more clearly distinguished between synthetic outcomes and downstream practical implications in the text, avoiding relying on confident tone in place of methodological rigor, and strengthened the logical link between source-base transparency and final claims. These revisions have significantly improved the scientific defensibility and structural stability of the manuscript, with claims better proportioned to methodological support. We are truly grateful for the reviewer’s careful guidance and valuable comments.

14. K2. Structural coherence

The manuscript is now structurally coherent in broad sequence, and that is an important strength. The reader can follow the line of movement from review framing and literature-search description into conceptual clarification, quantification methods, driving factors, practical improvement approaches, future research directions, and conclusion. This is no longer a loose or wandering review. The manuscript has a recognisable path through its material. The front of the paper is stronger than before, but it is still the least settled part of the structure. The title, Abstract, and Introduction now point more clearly to a review article, and the added search paragraph improves the paper’s opening architecture. The difficulty is that the opening still has to do too much work at once. It establishes significance, introduces the literature base, signals the review route, and begins to announce broad practical relevance. That means the front of the manuscript is improved, but still slightly overburdened. The middle of the paper is the most coherent part. The sequence from conceptual connotation to quantification methods and then to driver analysis is logical and well aligned with the manuscript’s central subject. The addition of the new discussion section strengthens that coherence further because it gives the review a more recognisable integrative centre rather than leaving the paper as a chain of adjacent thematic blocks. This middle is the part of the manuscript that most clearly justifies the review’s existence. The coherence weakens somewhat again near the end, though not because the later sections are misplaced. The practical approaches, future directions, and conclusion all follow logically from the earlier sections. The problem is that the scale of the language begins to widen more quickly than the structural sequence itself requires. In other words, the manuscript remains orderly, but the later interpretive reach is slightly broader than the earlier methodological and comparative grounding fully secures. That is not a failure of sequence. It is a softening of structural discipline at the edges. So the structural judgement here should be stated carefully. The manuscript is no longer weak because its parts do not fit together. Its parts do fit together. The remaining issue is that the opening is still carrying a little too much, the middle is stronger than the edges, and the closing sections widen in scope faster than the review’s most secure structural base fully supports. The paper is therefore coherent in organisation, but not yet equally strong in all parts of its architecture. Actions-K2: 1. Keep the present middle architecture, because the manuscript now has a clear and workable centre. 2. Lighten the opening burden by separating significance, review method, and contribution more cleanly. 3. Preserve the new discussion section, because it improves the structural continuity of the paper. 4. Tighten the later sections so that practical and future-oriented language grows from the review body more proportionately. 5. Aim for a structure in which the opening promise, middle synthesis, and final claim scale feel equally strong rather than middle-strong and edge-softened.

Ans: We sincerely appreciate the reviewer’s professional, detailed, and highly constructive comments on the structural coherence of the manuscript. We fully agree that although the overall framework is rational and the middle part is logically solid, the introduction is still overburdened, the concluding sections expand somewhat excessively, and the strength of the two ends is not comparable to that of the middle part. We have carried out systematic revisions in accordance with the suggestions. During the revision, we retained the core logical framework of the middle part, ranging from conceptual connotation and quantification methods to driving mechanisms, as well as the newly added integrative discussion section, which maintains its advantages of coherent structure and solid argumentation. At the same time, we refined the opening part by more clearly separating research significance, review methodology, and research contributions to reduce information overload. For the concluding sections, we appropriately tightened the scope of discussion so that practical implications and future prospects are derived more proportionately from the main review content. Through these adjustments, the ambition of the introduction, the synthetic strength of the middle part, and the scale of the final claims become more balanced, making the overall structure more stable, rigorous, and coordinated. We sincerely thank the reviewer for the careful guidance, which has significantly improved the structural integrity and logical coherence of the manuscript.

15. K3. Interpretive restraint

This remains one of the manuscript’s more sensitive zones. The paper has clearly improved, and the new Section 5 helps it interpret the literature in a more integrated way. But the review still tends at times to move from organised synthesis into higher-level implication too readily. The problem is not that the manuscript says unreasonable things. The problem is that it sometimes says reasonable things at a slightly larger scale than the review’s methodological exposure and comparative discrimination have fully earned. This is especially visible in the Abstract, parts of the Discussion, and the concluding final paragraph. Interpretive restraint is strongest where the paper stays close to differences among formulas, methods, ecological settings, and interacting driver classes. It is weaker where it moves into language about direct support for diagnosis, restoration evaluation, water security, sustainable ecological construction, and carbon-neutrality goals. Those formulations could be softened or better bounded without weakening the paper’s real contribution. The future directions section is also ambitious. Some of that ambition is justified, because identifying limitations and prospects is part of a review article’s role. But the section still edges close to becoming a programme statement in places, especially where new technological and interdisciplinary pathways are described with strong normative forward momentum. So interpretive restraint is improved, but still not complete. The manuscript is not wildly overstated. It is simply not yet fully disciplined at the boundary between what the review shows and what the authors would like the field to do next. Actions-K3: 1. Soften high-level implication language where it outruns the demonstrated synthesis. 2. Keep future directions clearly marked as proposals rather than as evidence-led findings. 3. Distinguish field significance from review-specific contribution more consistently. 4. Trim phrases suggesting direct practical applicability unless the review has clearly established that level of support. 5. Let the manuscript finish on a distilled review judgement rather than a widened agenda.

Ans: We sincerely appreciate the reviewer for the professional and pertinent comments on the interpretive restraint of the manuscript. We fully agree with the issues pointed out, including the somewhat overextended interpretations, overly strong statements on high-level implications and practical applications, and slightly ambitious future directions, and have made comprehensive revisions accordingly. In the revised manuscript, we have softened and bounded the high-level implication statements in the Abstract, Discussion, and Conclusion that exceed the support of the synthesized evidence, to ensure they align better with the scope of this review. We have more consistently distinguished the general significance of the field from the specific contribution of this review, and trimmed expressions implying direct practical applicability without sufficient evidence. Future research directions are clearly presented as proposals rather than evidence-based findings, and the concluding section has been tightened to end on a distilled, focused judgement rather than an overly broad agenda. Meanwhile, we have maintained the rigorous comparisons and interpretations in the core sections on quantification methods and driving factors. These revisions have enhanced the interpretive discipline and proportionality of the manuscript, ensuring all claims are well supported by the review. We are truly grateful for the reviewer’s careful guidance and valuable comments.

16. K4. Evidential spine and overall readiness

This manuscript is now best described as middle-strong with softened edges and a still partly exposed bridge. The opening is improved because review identity and literature-search language are more visible than before, but the bridge from retrieval to inclusion to thematic synthesis remains only partly secured. The middle carries the manuscript well. The ending is more structured, but still enlarges somewhat. The load-bearing middle is the clearest strength. Sections 2 to 5 now give the paper a coherent thematic and analytical centre, especially through Table 1, Table 2, the driver sections, and the new integrative discussion. This is where the manuscript is most persuasive. The bridge integrity remains the main problem. The paper now says more about how literature was gathered and screened, but the source-base logic still does not feel fully robust enough for the scale of synthesis later attempted, particularly in light of the front-end count inconsistency. This is why the principal break remains methodological-synthetic rather than merely linguistic. The closing distillation is improved but not yet fully disciplined. The numbered conclusion gives the paper better form, yet the manuscript still uses its integrated review body to support some broader practical and policy-facing language that exceeds the narrowest defensible contribution. The evidential spine therefore holds, but not yet at maximum tension. My final readiness judgement is that the manuscript has moved substantially closer to peer-review readiness, but still needs further revision before it is fully secure as a review article. The revisions have been serious and meaningful. The paper is no longer exposed in the same way as the earlier version. But because the principal break remains active, I would still place it in the stronger end of major revision rather than in clean peer-review readiness. Actions-K4: 1. Fix the bridge first: make the review-method route internally consistent and more explicit. 2. Keep the strengthened middle sections, because they now carry the manuscript well. 3. Narrow the final contribution to what the review most securely establishes. 4. Reduce closing enlargement so the edge matches the strength of the middle. 5. After those changes, do one final language and presentation sweep to bring the manuscript into a more settled review form.

Ans: We sincerely appreciate the reviewer’s comprehensive, rigorous, and highly insightful comments on the evidential spine and overall readiness of the manuscript. We fully agree that the manuscript now has a strong middle section but relatively softened edges, and that the logical bridge from literature retrieval to inclusion and thematic synthesis still needs further consolidation. We have carried out systematic revisions strictly following the reviewer’s suggestions. In the revision, we first focused on improving the core methodological section, clarifying and unifying the complete process and numerical relationship from literature retrieval, screening to final inclusion, ensuring the methodological logic is consistent and credible. We retained and further strengthened the core content from Sections 2 to 5, which represent the most persuasive part of the manuscript supported by Table 1, Table 2, driver analysis, and the new integrative discussion. On this basis, we further tightened the statement of contribution in the conclusion to precisely reflect the most robustly supported scope of the review, and reduced overly broad practical and policy-oriented statements beyond solid evidence, so that the strength of the ending matches that of the middle part. Finally, we conducted a final check on language expression and formatting to refine the manuscript into a more coherent and complete review. We are truly grateful for the reviewer’s professional and meticulous guidance. These valuable comments have greatly improved the academic rigor and integrity of the manuscript, and we believe the revised version has been significantly enhanced.

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

This revised manuscript is materially better than the earlier submission because it now declares itself clearly as a review, gives the reader a visible literature-search route, and organises much more of the paper around quantification methods, driving factors, practical approaches, limitations, and future work. The strongest gain is that the paper no longer arrives as a loose thematic survey. It now looks recognisably like a review article with a discernible internal plan.

The principal structural break, however, remains the bridge between the stated source base and the synthetic weight carried by the paper. The Abstract reports retrieval of 150 scientific publications, while the Introduction states that 80 valid papers were finally selected after secondary screening. That discrepancy is not a small clerical scuff. It signals that the review route is visible, but still not controlled clearly enough at the exact point where a review article must earn confidence.

The main secondry weakening is enlargement of the paper’s contribution language beyond what the visible review design securely carries. This appears in the Introduction, where the manuscript moves quickly toward ecosystem health diagnosis, early warning of land degradation risk, water management and decision-making claims, and it appears again in Figure 2 and in the Conclusion, where the paper extends toward ecological stability, water security, and climate-response support. The manuscript is stronger at organised coverage than at keeping its final claims within the demonstrated review base.

The paper’s best zone is the middle body. The discussion of calculation indices, the recognition of ANPP, BNPP and NDVI issues, the method-family summaries, and the categorisation of driver groups give the article a useful organising spine. Table 1 and Table 2 are doing real work here. They help the paper move beyond a flat literature recital toward a more ordered review.

My overall judgement is major revision. This is no longer a weak review in a simple sense. It contains substantial material and a clearer review identity. But the manuscript is not yet ready for acceptance because the review-method architecture, source-base control, and contribution control still need further work. The paper should now be revised not by adding more topic area, but by making the existing article more exact about what it reviewed, how it reviewed it, and what conclusions the selected literature truly supports.

 

A. Title, Abstract and Article-Type Alignment

The title is an improvement because it now identifies the paper as a review and centres the manuscript on quantitative methods and driving factors of precipitation use efficiency. That gives the article a clearer disciplinary shape and a more accurate reader contract at the point of entry.

The Abstract is stronger than before because it states the databases used, reports retrieval activity, and lists the major topical blocks of the paper. That is a genuine step forward. Yet the Abstract still carries too much programme-like material and too many downstream promises for a review whose method description remains compressed. It tries to do definition, scope, methodology, synthesis, application and future agenda all at once.

The sharpest front-end problem is the unresolved movement from retrieved records to retained literature. The Abstract says 150 scientific publications were retrieved, but the Introduction later says 80 valid papers were finally selected. A review article can withstand large screening losses, but it cannot afford uncertainty about the number that actually constitutes the evidence base.

The Abstract also overstates the eventual deliverable. It presents the paper as providing theoretical references and scientific bases for revealing response mechanisms to climate change, improving ecosystem resilience and stability, optimising water resource management, and promoting sustainable ecological construction. Those are broad field-level outcomes. The manuscript, as presently built, more securely offers an organised review of concepts, indices, method families, reported drivers and enhancement routes.

The keywords are serviceable but still slightly generic and partly duplicative of the title and first-page language. They would do more work if they reflected the paper’s actual review engine more precisely, for example the calculation indices, driver categories and review design. At present they describe the territory, but not the paper’s most distinctive organising contribution.

Actions for A

1. Make the retrieved-to-included literature count identical and explicit across the Abstract and main text.

2. Recast the Abstract around one review deliverable, not six downstream ambitions.

3. State the retained evidence base in the Abstract, not only the initial retrieval count.

4. Reduce future-agenda material in the Abstract and reserve more of it for the end of the paper.

5. Revise the keywords so they reflect the paper’s actual review structure and method emphasis.

 

B. Introduction and Review Route

The Introduction shows that the authors understand why PUE matters in dryland and alpine systems, and it links that importance to climate variability, precipitation behaviour and ecosystem productivity. The paper is at its most persuasive when it stays close to that terrain. The discussion of dryland scarcity and alpine phase-change loss is one of the better local parts of the opening.

A useful improvement is the addition of a review-method paragraph in the Introduction. The manuscript now tells the reader that all data and information were obtained from public literature, that Web of Science and CNKI were used, and that material was second-screened with inclusion and exclusion criteria before extraction of titles, keywords, authors, methods, conclusions and references. This was necessary and welcome.

The difficulty is that the method route is still reported more as assurance than as inspectable review design. The paper says that unified inclusion and exclusion criteria were used, but those criteria are not sufficiently shown. It says that key information was extracted, but it does not yet give the reader a compact audit trail showing document types retained, screening sequence, exclusion logic, or the structure of the extracted dataset.

The Introduction then expands rapidly into a significance paragraph that goes well beyond a careful review opening. The manuscript claims that PUE serves as a diagnostic indicator of ecosystem health and stability, offers early warning of land degradation risk, reveals water-heat coupling, guides water-saving practice, and supports scientific decision-making for ecological protection and regional sustainable development. That suite of claims is larger than the review route currently demonstrated.

For a review article, the Introduction should do three things very clearly: define the problem, define the review scope, and define the paper’s organising logic. The first of these is mostly in place. The second and third are only partly in place. The manuscript still needs a cleaner statement telling the reader exactly what kinds of literature were synthesised, what was compared across them, and what kind of conclusion this paper is entitled to draw.

Actions for B

1. Add a compact review-method table or flow summary in the Introduction or Methods-equivalent section.

2. State the inclusion and exclusion criteria directly, not by reference only.

3. Clarify whether theses were treated on the same footing as journal articles and why.

4. Replace the enlarged significance paragraph with a more exact statement of scope and deliverable.

5. Tell the reader what the review compares and what it does not attempt to do.

 

C. Core Conceptual Coverage and Quantification Methods

The manuscript handles the conceptual origin of PUE reasonably well. The derivation from water use efficiency, the link to NPP, and the distinction between NPP, ANPP and BNPP give the reader a workable basis for the rest of the paper. This is one of the clearer explanatory stretches in the article.

The discussion of ecological connotation is energetic and wide-ranging, but it also shows the manuscript’s habit of enlarging PUE into a near-universal indicator. The paper presents PUE as a route into ecosystem health, degradation diagnosis, resilience, drought monitoring, restoration assessment, crop yield improvement, and climate-risk early warning. Some of that may be justified in parts of the literature, but the review voice needs more caution when moving from reported uses to the paper’s own synthesis.

Section 3.1 is stronger because it identifies real differences among PUE calculation routes. The discussion of NPP-based, ANPP-based, NDVI-based and BNPP-related issues gives the paper substance. The point that ANPP-only approaches can miss below-ground allocation, particularly across precipitation regimes, is especially useful and belongs near the centre of the article’s scientific contribution.

Table 1 is valuable because it gives the paper an organising device rather than leaving the methods material as loose prose. It shows formulas, variable meanings, applications and scenarios. That said, the table would be stronger if the surrounding text were more comparative and less accumulative. The paper often lists methods capably, but less often tells the reader which method families are safest, weakest, or most conditional under specific review-relevant circumstances.

The heading “3.2. Provide support for research methodologies and technical approaches” is also a signal that this section still needs editorial repair. The issue is not only language. The heading suggests a support function rather than a synthetic section. A review article at this point should be telling the reader what method combinations have been used in the field, what they allow, and where they leave uncertainty unresolved.

Actions for C

1. Keep the ANPP, BNPP, NDVI and NPP comparison as a central analytic thread.

2. Rework Section 3.2 so it reads as synthesis, not as a support note.

3. Add a short comparative paragraph explaining when each index route is most dependable and where it becomes weak.

4. Reduce repeated “importance” language and increase discriminating method judgement.

5. Make the paper’s own view clearer on what the field has still not resolved in PUE calculation.

 

D. Driving-Factor Synthesis

The manuscript’s coverage of driving factors is broad and, in places, genuinely useful. Temperature, precipitation, topography, vegetation, soil and human activity are all treated as part of a multi-driver system rather than as isolated variables. That multi-driver orientation is a strength.

The discussion of precipitation gradients is among the stronger parts of the whole review. The recognition that PUE may show alternating positive and negative relationships or unimodal behaviour across moisture regimes is scientifically important, and the manuscript handles that better than it handles many of its broader application claims. The specific reference to a peak around 400 to 500 mm on the Qinghai-Tibet Plateau gives the section concrete value.

The section on tpography and geomorphology is also serviceable, especially where altitude, slope and aspect are linked to hydrothermal redistribution and vegetation behaviour. The paper is strongest when it explains how these factors change water availability, biomass and species composition rather than when it generalises immediately to large system outcomes.

The vegetation and soil section contains useful material, especially on root systems, wetland buffering, alpine steppe limitations, alpine meadow responsiveness, vegetation cover, and soil-water relations. But the prose still leans more toward compendium than synthesis. The review would improve if it separated well-supported recurrent findings from context-bound observations more clearly.

The key issue in this whole block is that the paper successfully assembles reported drivers, but is less successful at ranking, sorting, or judging them across scales and study types. A good review in this area should not only state that many factors matter. It should tell the reader where the literature is relatively settled, where it is mixed, and where results are likely to shift with ecosystem type, scale or index choice.

Actions for D

1. Add one synthetic subsection that distinguishes recurrent findings from mixed findings.

2. Separate scale-dependent results from results treated as more general in the literature.

3. Use the precipitation-gradient discussion as a model for the rest of the driver section.

4. Tell the reader where index choice alters the apparent strength of specific drivers.

5. Reduce repeated “many factors affect PUE” statements and increase comparative judgement.

 

E. Practical Approaches, Limitations and Future Directions

The practical-approaches section is helpful because it tries to convert the review into usable pathways such as infiltration and storage improvement, evaporation control, rainwater harvesting, drought-tolerant vegetation and grazing management. This gives the paper applied relevance and prevents the review from becoming purely descriptive.

At the same time, this section exposes a persistent boundary issue. Much of the paper’s source base, as visible from the references and the body, is centred on precipitation use efficiency literature with strong China, alpine, grassland and dryland weight. Practical prescriptions therefore need to be handled with care. The article is at risk of moving from literature summary to general management advice too quickly.

The limitations section is better than in many reviews because it does acknowledge unresolved areas, including cross-region applicability, multi-factor interactions, scale expansion, time-lag effects and extreme climate influences. This self-critique is one of the manuscript’s healthier features, and it should be used more actively to discipline the paper’s own claims.

The future-directions section is ambitious and current. Interdisciplinary collaboration, large-span remote sensing, multi-source integration, stable isotope tracing, eco-hydrological modelling and machine learning are all sensible field directions. But the section sometimes reads more like a forward-looking agenda paper than the closing movement of a carefully bounded review.

Overall, this section is useful, but it needs stronger internal separation between what the reviewed literature already supports, what the review infers as likely next steps, and what belongs to a more speculative horizon. Once those three layers are separated, the paper will read as more exact and more trustworthy.

Actions for E

1. Distinguish clearly between literature-backed management routes and broader field aspirations.

2. Use the limitations section to place visible boundaries on the practical claims.

3. Shorten the future-directions block and make it more closely tied to the review findings.

4. Avoid presenting forward-looking technologies as if they resolve present review uncertainties.

5. Show which future directions arise directly from gaps in the retained literature base.

 

F. Conclusion and Contribution Control

The Conclusion is improved because it is more structured and now gives numbered take-home points. That is better than a single sweeping ending. It helps the reader see the article’s intended contribution more clearly.

The difficulty is that the Conclusion still overreaches relative to the demonstrated review route. It claims that the scientific status of PUE is clarified, that the paper confirms multi-category synergistic driving, that practical approaches are systematically summarised, and that major shortcomings and future directions are established. Some of this is fair as a review summary. Some of it sounds more final than the paper’s method visibility allows.

A more serious concern is the language that follows. The manuscript says the study highlights standardisation of quantification methods, integration of driving mechanisms, and the empirical nature of research conclusions, and then moves to direct support for ecological degradation diagnosis, restoration effect evaluation, efficient precipitation use, ecosystem resilience, water security, sustainable ecological construction, climate-change response, and carbon peaking and carbon neutrality goals. This is too much ground for the present review article to claim securely.

There is also an article-type issue here. This is a review paper, not a primary empirical investigation. Phrases such as “the empirical nature of research conclusions” and some of the downstream support language blur that distinction. The Conclusion should speak as a review that organises and judges existing literature, not as if the paper itself has generated a new direct field evidence base.

The Conclusio should therefore be rewritten around the paper’s narrowest secure achievement: a structured review of PUE concepts, indices, method families, reported drivers, practical enhancement routes, current limitations and plausible future directions. Once the ending is brought back to that centre, the whole manuscript will become more convincing.

Actions for F

1. Rewrite the Conclusion from the standpoint of a review article, not a field study.

2. Remove or soften downstream claims about resilience, water security and carbon-goal support.

3. Keep the numbered structure, but shorten each point and tie it to visible review content.

4. Replace enlarged policy language with clearer statements of what the review actually shows.

5. End with a bounded conclusion, not a field-wide manifesto.

 

G. Tables, Figures and Presentation

The tables and figures are carrying much of the paper’s value. Table 1 gives real explanatory service by distinguishing formulas, variables, uses and scenarios. Table 2 is also useful because it groups method families for spatiotemporal change, contribution analysis and multi-factor relationships. These visual elements help the manuscript move beyond narrative accumulation.

Figure 1 is serviceable as background support because it connects NPP estimation logic and model pathways. It helps explain why PUE studies often rely on different productivity representations and why remote-sensing products enter the field so strongly. That figure belongs in the paper.

Figure 2 is the more exposed visual object. The manuscript describes it as presenting a full-chain logic from driving factors through hydrological processes to PUE response and ecological stability, including soil and water conservation, irrigation security, productivity improvement and broader ecological outcomes. That is visually ambitious, but it places too much inferential weight on a single diagram. The figure extends further than the review article has yet earned.

Figure 3 is more comfortable because it serves a practical summarising function rather than claiming to resolve a full system logic. It is still advisable, however, to make sure that each practical strategy shown there is explicitly tied back to the literature types and settings from which it arose.

Editorially, the presentation still needs more care. Forms such as “Figure.1”, “Table.1”, and the awkward Section 3.2 heading weaken polish. These are not the deepest problems in the paper, but in a review article they matter because the reader needs a strong sense of order, control and exactness from start to finish.

Actions for G

1. Keep Table 1 and Table 2 as central visual supports.

2. Rework Figure 2 so it shows reviewed relationships without carrying oversized downstream claims.

3. Make sure Figure 3 is tied directly to reviewed settings and evidence types.

4. Correct all figure and table labelling and punctuation forms.

5. Replace the current Section 3.2 heading with a clear synthetic heading.

 

H. References, Source Base and End-Section Control

The visible reference list suggests a substantial and reasonably current literature base. In the excerpts available from the reference section, publication years run from at least 1998 to 2025, with a strong recent presence in the last several years. That is a sound starting point for a contemporary review.

The more important issue is not volume or recency alone, but the character of the source base. The Introduction itself emphasises dryland ecosystems and the Qinghai-Tibet Plateau, and the references visible here show strong Chinese, alpine, grassland and dryland concentration. That source-base profile is acceptable, but it means the review must be careful when making broad global statements or wide management claims.

There is also a review-design question about document type. The manuscript says the search covered peer-reviewed journal articles, doctoral dissertations and master’s theses. That mixed-document base may be defensible, but it needs clearer handling because a review article should tell the reader whether all document types were weighted equally, screened differently, or used for different purposes.

A further point concerns the Data Availability Statement. The paper says that the raw data supporting the conclusions will be made available on request, yet earlier it states that all data and information came from publicly available literature and that key information was extracted from each paper to create the review dataset. For a review article, the most useful thing would be not a vague raw-data statement, but direct availability of the extracted dataset, screening record and coding structure.

Overall, the references are not the manuscript’s weakest area, but they are part of the principal break because the reader still cannot inspect the review dataset that stands between the search route and the synthesis claims. If that extracted dataset were supplied, the paper’s defensibility would improve immediately.

Actions for H

1. Clarify how peer-reviewed articles, doctoral theses and master’s theses were handled in the review.

2. Supply the extracted review dataset as supplementary material.

3. Replace the vague data-availability wording with a review-appropriate statement.

4. Add a short note on the geographical and ecosystem centre of gravity of the retained literature.

5. Keep global claims within what that visible source base can safely support.

 

I. Language, units, style, and local expression

The manuscript is improved at sentence level relative to the earlier version, but the prose still reads as revised rather than fully settled. The most persistent issue is not simple grammar. It is syntactic overloading. Many sentences carry too many linked ideas in one movement, especially in the Abstract, the Introduction, the later discussion, and the Conclusion. That makes the review sound more effortful than assured, and in a review article that matters because comparative synthesis depends on clarity of movement rather than on sheer informational volume.

The opening pages show this clearly. The manuscript often runs several claims, contextual points, and significance statements together without enough structural release. As a result, the paper sometimes sounds broader and more confident than its sentence control supports. This is especially noticeable where climate framing, ecological importance, and PUE significance are stacked quickly in the Introduction.

There are also still local editorial-control issues that should not remain at this stage. The manuscript uses forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading, “Provide support for research methodologies and technical approaches”, is still awkward as academic English. These are not fatal defects, but they signal that the paper has not yet reached final surface control.

The style problem is also tied to the paper’s enlarged significance language. Phrases around ecosystem health diagnosis, land-degradation early warning, resilience, water-resource optimisation, and sustainable ecological construction appear repeatedly in ways that are not always matched by equally restrained review wording. In this manuscript, style and interpretation are linked: the prose often enlarges before the synthesis has fully consolidated.

Units are not the manuscript’s main problem, but presentation consistency still matters because formulas, tables, labels, and technical terms are carrying much of the article’s scientific work. The remaining language issue is therefore not whether the manuscript is readable. It is whether it sounds editorially complete, proportionate, and calm at the exact points where it asks the reader to trust its synthesis. At present, it is not yet fully there.

Actions for I

1. Shorten clause-heavy sentences, especially in the Abstract, Introduction, Discussion, and Conclusion.

2. Correct all residual label and punctuation forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”.

3. Rewrite the Section 3.2 heading into clear academic English.

4. Reduce significance-heavy phrasing where the manuscript moves beyond its most clearly supported synthesis.

5. Do one final consistency sweep across labels, formulas, captions, punctuation, and overall presentation style.

 

J. References, citations, and reference-year spread

The reference list is substantial and broadly relevant to the subject. It is also clearly centred on precipitation use efficiency in grassland, alpine, dryland, and related ecological settings, with strong Chinese and plateau-focused representation. That source-base profile fits much of the manuscript’s body, but it also means the paper should be more careful whenever it moves into wide global or general ecological claims.

On my reading of the uploaded reference list, the bibliography contains 50 references. The earliest visible publication year is 1998 and the most recent is 2025. The median publication year is 2019. The most frequent reference years are 2020 and 2023, which tie as the modal years. About 70% of the references fall within the last ten years of the most recent reference year, so the paper is not relying mainly on dated literature. The decade spread is weighted strongly toward the 2010s and 2020s, with only light representation from the 1990s and 2000s. That is a healthy recency profile for a review article. Derived from the uploaded PDF’s reference list.

The stronger bibliographic issue is not age but spread and evidential positioning. The list is heavily concentrated in grassland, alpine, dryland, Qinghai-Tibet Plateau, Inner Mongolia, Loess Plateau, and related Chinese ecological settings, with some wider dryland and Australian contributions. That is a coherent literature base for the paper’s central terrain. But it does not fully support the scale of some of the manuscript’s broadest diagnostic, resilience, and management claims. The manuscript should therefore align the size of its concluding claims with the actual centre of gravity of the reference base.

There is also a review-design issue in how sources are treated. The manuscript states that peer-reviewed journal articles, doctoral dissertations, and master’s theses were all included, yet it does not explain whether these were weighted equally, screened differently, or used in distinct ways. For a review article, that matters because the reader needs to understand not only what was included, but how heterogeneous source types were handled.

Finally, the Data Availability Statement is still not well matched to the article type. The paper says that raw data supporting the conclusions will be made available on request, but the article is a literature review built from extracted information from existing publications. What the reader really needs is not a vague raw-data promise, but access to the extracted review dataset, screening logic, and possibly the coding or extraction template used to organise the included papers.

Actions for J

1. Keep the current literature base, because it is current and thematically coherent.

2. State more explicitly that the reference base is concentrated in alpine, dryland, grassland, and especially Chinese or plateau-centred contexts.

3. Clarify how peet-reviewed articles, doctoral theses, and master’s theses were handled in the review.

4. Replace the present data-availability wording with a review-appropriate statement tied to the extracted dataset.

5. Tighten broad ecological and management claims where they appear to generalise beyond the actual source-base centre of gravity.

 

K1. Contribution and Evidence

The broad claimed contribution of the paper is very large. Across the Abstract, Introduction and Conclusion, the manuscript presents itself as a source of theoretical reference and scientific basis for climate-response mechanisms, ecosystem resilience and stability, ecological diagnosis, water management, restoration evaluation, sustainable construction and carbon-related goals. That is a wide contribution field.

The evidence actually shown in the manuscript is narrower and more specific. It consists of a selected literature review organised around concepts of PUE, calculation indices, method families, reported driver categories, practical enhancement approaches, limitations and future research directions. That is still useful and publishable material, but it is not the same as directly establishing all the wider downstream claims.

The paper’s most secure scientific contribution lies in the organised comparison of how PUE has been quantified and analysed across different study designs and indices, and in the effort to assemble driver categories into one review structure. That is where the review has the clearest evidential footing.

Where the paper becomes less secure is when it treats that organised review as if it were enough to carry field-level claims about diagnosis, stability, resilience and broad policy support. The manuscript itself acknowledges unresolved inconsistencies, cross-scale issues, and gaps in mechanism interpretation. Those admissions are important and should temper the final contribution language much more strongly than they currently do.

My judgement here is that the manuscript has a real contribution, but not the one it currently claims at full size. It should present itself as a strong organising review of PUE research routes and reported controls, not as a near-settling statement on what PUE can already do across ecosystems and management domains.

Actions for K1

1. Shrink the formal contribution claim to match the reviewed evidence base.

2. Keep the strongest emphasis on method families, indices and reported drivers.

3. Use the manuscript’s own limitations section to discipline its contribution language.

4. Remove any wording that makes the review sound like direct empirical proof.

5. State one clear, bounded contribution in the Abstract, Introduction and Conclusion.

 

K2. Structural Coherence

The manuscript now has a recognisable architecture: Introduction, conceptual material, quantification methods, driving factors, practical approaches, limitations, future work and conclusions. That is a substantial improvement and gives the review a workable outer structure.

The main break sits not in the outer structure, but in the transition from review design to synthetic authority. The paper tells the reader that literature was searched, screened and extracted, but it does not yet give enough visible design detail to support the breadth of the later synthesis. That makes the middle and end of the paper more confident than the review route presently warrants.

Within the body, the movement from concept to methods to drivers is broadly logical. The paper reads most coherently when it stays within those internal scientific blocks. The structure becomes less steady when it moves from driver synthesis to system-level ecological outcomes and management implications. That is the point where the article begins to stretch away from its clearest evidential footing.

The ending also reflects this structural issue. The Conclusion recaps the organised review material, but then enlarges into downstream claims that would require a more inspectable review architecture and a more explicitly comparative synthesis than the manuscript currently offers.

So the paper is structurally improved, but not yet fully coherent at the level that matters most in a review article. Its sections exist in the right order. The harder remaining task is to make sure each later section is genuinely earned by the route that comes before it.

Actions for K2

1. Make the review-design section more visible and more exact.

2. Check every major conclusion against the source-base description that precedes it.

3. Reduce the size of the move from driver review to ecological and management claims.

4. Use one internal thread through the paper, such as indices, scale and driver interpretation.

5. Revise the ending so it follows directly from the review route already shown.

 

K3. Interpretive Restraint

This revision is better than the earlier one because it no longer sounds as if it is simply celebrating the topic. It now includes visible limitations, methodological contradictions and future gaps. That is a positive sign.

Even so, the paper still needs more restraint in how it states what the literature has established. Terms such as “clarified”, “confirmed”, “full-chain logic”, and broad downstream support language make the paper sound more settled than the review base, as currently described, allows.

The Introduction is one place where this shows early. The paper quickly turns PUE into a diagnostic indicator for ecosystem health and stability, an early-warning index for degradation risk, a guide for water-saving practice, and a basis for scientific decision-making. Those uses may appear somewhere in the literature, but the review voice should distinguish more clearly between reported use, likely use, and demonstrated review finding.

Figure 2 and the Conclusion show the same tendency. They both move toward a wide chain from drivers and hydrology to ecosystem stability and management outcomes. The paper would gain authority, not lose it, by saying less where the evidence path is not fully shown.

My view is that the manuscript is closest to a publishable review when it speaks in a disciplined synthetic voice, especially in the methods and driver sections. It is furthest from that standard when it turns review results into near-programmatic declarations about what PUE research now enable.

Actions for K3

1. Replace over-final verbs with more careful review language.

2. Separate reported findings from the paper’s own wider inference.

3. Reduce enlarged claims in the Introduction, Figure 2 narrative and Conclusion.

4. Keep the paper in review voice throughout, especially at the end.

5. Let the limitations section do real interpretive work, not only formal acknowledgement.

 

K4. Evidential-spine stability

The manuscript now has a more visible internal spine than the earlier version because the middle sections are no longer scattered. The article moves from conceptual framing into quantification methods, then into driving factors, practical approaches, limitations and future directions in a way that a reader can broadly follow. That gives the paper a recognisable internal route. The difficulty is that the spine is strongest in the middle and weaker at the front and back ends, which means the manuscript is improved but not yet fully stable as a review article.

The weakest link remains the bridge between literature retrieval and later synthesis. The Abstract states that 150 scientific publications were systematically retrieved, while the Introduction states that 80 valid papers were finally selected and included after second screening. A review article can certainly move from a larger retrieval pool to a smaller included set, but the paper does not yet show that transition clearly enough to carry the interpretive weight placed on the later synthesis. The review route is present, but it is still under-exposed at the exact point where the reader needs confidence most.

The central body then performs better than the opening. The paper gives useful comparative material on formulas, indices, method families and reported driving factors, and this is where the manuscript most convincingly earns its place as a review. Table 1 and Table 2 are especially important because they provide a clearer evidential base for the synthesis than the paper’s broader conceptual claims do. In other words, the manuscript’s strongest support lies in organised comparative coverage of methods and drivers, not in its largest statements about what PUE can already do for ecological diagnosis, resilience or management.

The spine weakens again in the final interpretive movement. The manuscript repeatedly enlarges from reviewed literature into broad claims about ecosystem health diagnosis, land-degradation early warning, water-resource optimisation, ecological stability, climate-response support, and sustainable construction. Those statements may be directionally understandable, but the paper’s own review design and source-base exposure do not yet justify them at that scale. This is why the manuscript still feels more expansive than settled in its concluding reach.

Overall, the manuscript’s evidential spine is now present and materially stronger than before, but it is still not fully secure from opening route to final claim. The paper no longer fails because it lacks substance. It now risks weakness because the review-method bridge remains thinner than the synthesis and conclusion require. My judgement is therefore that the manuscript is recoverable within its present identity, but only if the next revision concentrates on source-base clarity, comparative synthesis, and proportionate final claims rather than on further expansion of topic coverage.

Actions for K4

1. Make the review route fully explicit by distinguishing retrieval, screening and final inclusion clearly and consistently.

2. Let the strongest middle sections on indices, methods and drivers carry the paper’s main scientific value.

3. Rebuild the conclusion from the literature base actually retained, not from the widest possible implications of the topic.

4. Add supplementary material showing the extracted review dataset or screening structure so that the synthesis can be inspected more confidently.

5. Revise for evidential control, not for broader ambition.

 

L. Priority revisions

The first priority is to repair the review-method bridge. At present the manuscript asks the reader to trust a review route that is visible but still under-exposed. The discrepancy between 150 retrieved publications and 80 included papers is not just a number problem. It signals that the route from search to inclusion to synthesis is still not secure enough for the article’s interpretive weight. This must be corrected before any further polishing work.

The second priority is to narrow the contribution and claim scale. The manuscript’s strongest value lies in organising concepts, indices, methods, driver categories, enhancement approaches, and visible limitations. It is weaker when it claims direct support for ecosystem diagnosis, resilience, water security, and broader ecological decision-making. The paper should be rewritten around the narrowest defensible contribution rather than the widest possible significance.

The third priority is to strengthen comparative synthesis in the middle sections. The paper has good raw material in Table 1, Table 2, and the driver-analysis blocks, but it still leans too often toward organised listing rather than firmer comparison. The manuscript should tell the reader more clearly which method families, indices, and driver interpretations are robust, which are conditional, and where the literature remains mixed.

The fourth priority is to bring the Conclusion back within the review’s evidential reach. The paper’s ending still enlarges faster than the demonstrated review architecture supports. The numbered structure is useful and should be kept, but the final claims need to be trimmed back to what the retained literature actually allows the review to say confidently.

The fifth priority is surface and presentation control. This is not the main problem, but it is now one of the remaining readiness drags. Once the bridge, contribution scale, and synthesis quality are repaired, the manuscript should receive one final editorial sweep for dense sentence structure, awkward headings, label punctuation, and consistency across the visual and textual layer.

Priority revisions

1. Resolve the retrieved-versus-included literature route and make the review design inspectable.

2. Rewrite the contribution claim so that it matches the review’s actual evidential base.

3. Increase comparative judgement in the methods and driver sections.

4. Recast the Conclusion into a bounded review ending rather than a broad field-level projection.

5. Do one final language and presentation sweep only after the structural and evidential issues are fixed.

 

M. Overall readiness and contribution

This manuscript is now materially stronger than the earlier version and is clearly in a better state than a diffuse or under-structured review. It has a recognisable architecture, a stronger centre of gravity, and enough substance to justify further revision rather than dismissal. The middle sections on calculation routes, method families, and driving factors are now carrying real value.

Its readiness problem is concentrated rather than scattered. The article is no longer chiefly weakened by lack of material. It is weakened by the under-exposed review-method bridge and by a contribution scale that is still too broad for the route currently shown. That is an important distinction because it means the manuscript is repairable within its present identity.

The most defensible overall contribution of the paper is that it offers an organised review of PUE concepts, quantification routes, research methods, reported driver groups, practical enhancement pathways, and current research limitations. A slightly stronger version of that claim would be that it is particularly useful in comparing how PUE has been operationalised and in showing that reported behaviour is contingent on ecosystem type, precipitation regime, and multi-factor interaction rather than on one simple general rule. That is a worthwhile contribution. It does not need inflation to be valuable.

The paper is not yet ready for acceptance because the current review architecture still does not fully justify the breadth of the final claims. But it is ready for a focused major-revision round, and that matters. The manuscript has moved beyond basic structural weakness. It now needs evidential tightening, not conceptual expansion.

My overall judgement is therefore that the manuscript remains in the stronger end of major revision, with a credible path to external peer-review readiness if the next revision is disciplined and concentrated. The key is not to add more territory. It is to make the existing review more exact, more inspectable, and more proportionate in what it finally claims.

Actions for M

1. Treat the next round as a concentrated major revision, not as a broad expansion.

2. Present the paper’s contribution as an organised and comparative review, not as a near-field-settling statement.

3. Make the review dataset and screening route visible enough to support trust in the synthesis.

4. Align the scale of the final claims with the actual source base and review architecture.

5. Aim for a revised manuscript that is tighter, more inspectable, and less ambitious in tone, but stronger in credibility.

 

N. Evidential-Spine Judgement and Overall Readiness

The manuscript’s evidential centre now runs more clearly than before. There is a visible path from topic definition, to literature search, to conceptual explanation, to method families, to driver categories, to practical routes and future gaps. That is why this revised version is noticeably stronger.

But the centre of the paper is still not fully secure because the review-design description is thinner than the synthetic load later placed upon it. In other words, the source base is present, yet not inspectable enough. That is the exact location of the principal break. Once that break appears, the broader claims in the Introduction, Figure 2 and Conclusion begin to read as larger than the visible review route.

The secondary weakening then compounds the problem. Because the contribution language remains enlarged, the paper’s end claims ask the reader to grant more authority than the method route, source-base transparency and comparative synthesis have yet earned. This is why the paper feels improved but not yet settled.

The good news is that the necessary revision path is now clear. The manuscript does not mainly need more topics, more future technologies, or more importance language. It needs a firmer review-design display, a more exact comparative synthesis, and a conclusion brought back within what the retained literature can safely carry. Those are achievable revisions.

My readiness judgement is therefore as follows: not yet ready for acceptance, but now credibly in major-revision territory rather than in diffuse conceptual overreach. The manuscript has enough organised substance to justify further revision. What it does not yet have is a sufficiently demonstrated bridge between source selection, comparative synthesis and final claim size.

Actions for N

1. Repair the review-design-to-synthesis bridge first.

2. Resolve the retained-literature count and show the screening route clearly.

3. Add the extracted review dataset or coded summary as supplementary material.

4. Rebuild the final claims from the most secure middle sections outward.

5. Revise for readiness, not expansion.

 

N+. Broad Claimed Contribution Against the Narrowest Defensible Contribution

The broad claimed contribution of the manuscript is that it provides theoretical references and scientific bases for revealing PUE response mechanisms to climate change, improving ecosystem resilience and stability, optimising water resource management, promoting sustainable ecological construction, supporting ecological degradation diagnosis and restoration evaluation, and even contributing to climate-response goals at a larger systems level.

The narrowest defensible contribution is smaller, but still worthwhile. This paper offers an organised review of selected literature on PUE that explains the concept’s main calculation routes, compares commonly used method families, gathers reported driver categories, summarises practical enhancement routes, identifies visible current limitations, and maps plausible directions for future work.

A slightly stronger, but still defensible, version would be this: the review is particularly useful in showing how PUE has been operationalised through different indices and analysis routes, and in showing that reported PUE behaviour is contingent on ecosystem type, precipitation gradient, scale and driver combination rather than on a single universal rule.

What the paper should not yet claim is that the review itself directly establishes a reliable basis for wide ecological diagnosis, management optimisation across settings, or larger climate-goal support without first narrowing those statements to the visible source-base profile and the exact limits admitted by the paper itself.

If the authors revise the paper around the narrowest defensible contribution, the manuscript will become more credible, more readable and more publishable. In this case, saying less at the top and the end would actually allow the genuine value of the review to show more clearly.

Actions for N+

1. State the narrowest defensible contribution explicitly in the Introduction and Conclusion.

2. Remove broad field-changing language unless it is directly tied to the retained literature base.

3. Present the paper as an organised review, not as a direct ecological diagnostic tool.

4. Let the methods and driver sections carry the article’s main value.

5. Use the revised contribution statement consistently across title page, Abstract, Introduction and Conclusion.

 

Overall Recommendation

Major revision

This revised manuscript has moved forward in meaningful ways, especially in article-type clarity, middle-section organisation and explicit acknowledgment of limitations. But the paper still needs one more serious revision round centred on review-design visibility, source-base control and conclusion control before it is ready for acceptance.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Comments on the Quality of English Language

See report

Author Response

1. This revised manuscript is materially better than the earlier submission because it now declares itself clearly as a review, gives the reader a visible literature-search route, and organises much more of the paper around quantification methods, driving factors, practical approaches, limitations, and future work. The strongest gain is that the paper no longer arrives as a loose thematic survey. It now looks recognisably like a review article with a discernible internal plan.

The principal structural break, however, remains the bridge between the stated source base and the synthetic weight carried by the paper. The Abstract reports retrieval of 150 scientific publications, while the Introduction states that 80 valid papers were finally selected after secondary screening. That discrepancy is not a small clerical scuff. It signals that the review route is visible, but still not controlled clearly enough at the exact point where a review article must earn confidence. The main secondry weakening is enlargement of the paper’s contribution language beyond what the visible review design securely carries. This appears in the Introduction, where the manuscript moves quickly toward ecosystem health diagnosis, early warning of land degradation risk, water management and decision-making claims, and it appears again in Figure 2 and in the Conclusion, where the paper extends toward ecological stability, water security, and climate-response support. The manuscript is stronger at organised coverage than at keeping its final claims within the demonstrated review base. The paper’s best zone is the middle body. The discussion of calculation indices, the recognition of ANPP, BNPP and NDVI issues, the method-family summaries, and the categorisation of driver groups give the article a useful organising spine. Table 1 and Table 2 are doing real work here. They help the paper move beyond a flat literature recital toward a more ordered review. My overall judgement is major revision. This is no longer a weak review in a simple sense. It contains substantial material and a clearer review identity. But the manuscript is not yet ready for acceptance because the review-method architecture, source-base control, and contribution control still need further work. The paper should now be revised not by adding more topic area, but by making the existing article more exact about what it reviewed, how it reviewed it, and what conclusions the selected literature truly supports.

Ans: We sincerely appreciate the reviewer’s thorough and insightful comments on defining the appropriate scope of the manuscript’s contribution. We fully understand that the originally stated contribution is overly broad, as it extends to ecosystem resilience, water resource management, ecological degradation diagnosis, and climate‑response strategies. In contrast, the most defensible and realistic contribution of this article is to provide a systematic review of PUE research, including its core calculation methods, mainstream methodological frameworks, driving factors, improvement approaches, existing limitations, and future research directions. More importantly, this review clarifies how PUE is quantified using different indicators and analytical approaches, and highlights that PUE dynamics depend on ecosystem type, precipitation gradient, spatial scale, and combined driving factors, rather than a single universal principle. We will avoid any claims that this review serves as a direct ecological diagnostic tool or provides a broad scientific basis for large‑scale management and climate goals. Instead, we will explicitly state the focused, well‑supported contribution in the Introduction and Conclusion, and maintain consistent phrasing throughout the title page, Abstract, Introduction, and Conclusion. Broad, unsupported statements will be removed, and the core value of the manuscript will be centered on the methodological comparisons and driver analyses. Detailed revisions have been addressed in the above responses.

2. A. Title, Abstract and Article-Type Alignment

The title is an improvement because it now identifies the paper as a review and centres the manuscript on quantitative methods and driving factors of precipitation use efficiency. That gives the article a clearer disciplinary shape and a more accurate reader contract at the point of entry. The Abstract is stronger than before because it states the databases used, reports retrieval activity, and lists the major topical blocks of the paper. That is a genuine step forward. Yet the Abstract still carries too much programme-like material and too many downstream promises for a review whose method description remains compressed. It tries to do definition, scope, methodology, synthesis, application and future agenda all at once. The sharpest front-end problem is the unresolved movement from retrieved records to retained literature. The Abstract says 150 scientific publications were retrieved, but the Introduction later says 80 valid papers were finally selected. A review article can withstand large screening losses, but it cannot afford uncertainty about the number that actually constitutes the evidence base. The Abstract also overstates the eventual deliverable. It presents the paper as providing theoretical references and scientific bases for revealing response mechanisms to climate change, improving ecosystem resilience and stability, optimising water resource management, and promoting sustainable ecological construction. Those are broad field-level outcomes. The manuscript, as presently built, more securely offers an organised review of concepts, indices, method families, reported drivers and enhancement routes. The keywords are serviceable but still slightly generic and partly duplicative of the title and first-page language. They would do more work if they reflected the paper’s actual review engine more precisely, for example the calculation indices, driver categories and review design. At present they describe the territory, but not the paper’s most distinctive organising contribution. Actions for A. 1. Make the retrieved-to-included literature count identical and explicit across the Abstract and main text. 2. Recast the Abstract around one review deliverable, not six downstream ambitions. 3. State the retained evidence base in the Abstract, not only the initial retrieval count. 4. Reduce future-agenda material in the Abstract and reserve more of it for the end of the paper. 5. Revise the keywords so they reflect the paper’s actual review structure and method emphasis.

Ans: We are extremely grateful to the reviewer for the meticulous and professional comments on the title, abstract, keywords and positioning of this article. These constructive suggestions have provided significant guidance for optimizing the logical structure and academic expression of the paper. We have revised the manuscript strictly in accordance with the comments, and the detailed responses are as follows: We sincerely appreciate the reviewer's recognition of supplementing the information related to databases and literature retrieval in the abstract. We have streamlined the redundant stylized expressions and overly broad long-term application prospects in the abstract, avoiding the accumulation of contents such as definitions, research methods and application prospects. Regarding the discrepancy in the number of literature screening between the abstract and the introduction, we have unified the number of retrieved literatures and finally included literatures throughout the full text, clearly marking the valid literature base to ensure the rigor of research arguments. Meanwhile, we have revised the overstatement of research achievements in the abstract, accurately positioning the core contribution of this paper as systematically sorting out the concepts, calculation indicators, research methods and driving factors related to precipitation use efficiency, abandoning the extensive expression of application value. In addition, we have reduced the space for future research prospects in the abstract and integrated this part into the conclusion of the paper for further elaboration. We have adopted the reviewer's comments. Aiming at the problems that the original keywords are overly broad, redundant and repetitive with the title, we have redrafted the keywords combined with the review framework and methodological characteristics of this paper, supplemented contents such as calculation indicators and classification of driving factors, highlighting the research characteristics and innovations of this article (Lines 18-36 and Lines 37-38).

3. B. Introduction and Review Route

The Introduction shows that the authors understand why PUE matters in dryland and alpine systems, and it links that importance to climate variability, precipitation behaviour and ecosystem productivity. The paper is at its most persuasive when it stays close to that terrain. The discussion of dryland scarcity and alpine phase-change loss is one of the better local parts of the opening. A useful improvement is the addition of a review-method paragraph in the Introduction. The manuscript now tells the reader that all data and information were obtained from public literature, that Web of Science and CNKI were used, and that material was second-screened with inclusion and exclusion criteria before extraction of titles, keywords, authors, methods, conclusions and references. This was necessary and welcome. The difficulty is that the method route is still reported more as assurance than as inspectable review design. The paper says that unified inclusion and exclusion criteria were used, but those criteria are not sufficiently shown. It says that key information was extracted, but it does not yet give the reader a compact audit trail showing document types retained, screening sequence, exclusion logic, or the structure of the extracted dataset. The Introduction then expands rapidly into a significance paragraph that goes well beyond a careful review opening. The manuscript claims that PUE serves as a diagnostic indicator of ecosystem health and stability, offers early warning of land degradation risk, reveals water-heat coupling, guides water-saving practice, and supports scientific decision-making for ecological protection and regional sustainable development. That suite of claims is larger than the review route currently demonstrated. For a review article, the Introduction should do three things very clearly: define the problem, define the review scope, and define the paper’s organising logic. The first of these is mostly in place. The second and third are only partly in place. The manuscript still needs a cleaner statement telling the reader exactly what kinds of literature were synthesised, what was compared across them, and what kind of conclusion this paper is entitled to draw. Actions for B. 1. Add a compact review-method table or flow summary in the Introduction or Methods-equivalent section. 2. State the inclusion and exclusion criteria directly, not by reference only. 3. Clarify whether theses were treated on the same footing as journal articles and why. 4. Replace the enlarged significance paragraph with a more exact statement of scope and deliverable. 5. Tell the reader what the review compares and what it does not attempt to do. 

Ans: We are very grateful to the reviewer for the detailed, professional and highly constructive comments on the introduction section of this paper. We fully agree with the issues pointed out by the reviewer, and have comprehensively revised and improved the introduction content, the description of the review method, the definition of the research scope and the statement of research significance in accordance with the suggestions. The detailed responses are as follows: We appreciate the reviewer’s recognition of the elaboration on the importance of Precipitation Use Efficiency (PUE) in dryland and alpine ecosystems in the introduction, as well as the affirmation of the newly added paragraph on the review method. Following the reviewer’s comments, we have further strengthened the standardization and traceability of the review method, and added a concise summary table of the review process in the introduction or the corresponding method section, clearly showing the complete pathway of literature retrieval, screening, inclusion and exclusion. Meanwhile, we have directly and explicitly listed the detailed literature inclusion and exclusion criteria in the text, rather than only making general references, so that reviewers and readers can clearly verify the screening basis. Regarding whether dissertations were included on the same footing as journal articles, we have clearly stated the treatment approach and its justification in the text to ensure transparency and rigor in the literature screening process. To address the problem that the statement of research significance in the introduction was too broad, we have removed the overly extended descriptions of functions and applications, and replaced them with more precise statements of the research scope and core contributions that fit the actual content of this review, so as to avoid conclusions beyond the supportive capacity of the reviewed literature (Lines 88-113 and Lines 115-149).

4. C. Core Conceptual Coverage and Quantification Methods

The manuscript handles the conceptual origin of PUE reasonably well. The derivation from water use efficiency, the link to NPP, and the distinction between NPP, ANPP and BNPP give the reader a workable basis for the rest of the paper. This is one of the clearer explanatory stretches in the article. The discussion of ecological connotation is energetic and wide-ranging, but it also shows the manuscript’s habit of enlarging PUE into a near-universal indicator. The paper presents PUE as a route into ecosystem health, degradation diagnosis, resilience, drought monitoring, restoration assessment, crop yield improvement, and climate-risk early warning. Some of that may be justified in parts of the literature, but the review voice needs more caution when moving from reported uses to the paper’s own synthesis. Section 3.1 is stronger because it identifies real differences among PUE calculation routes. The discussion of NPP-based, ANPP-based, NDVI-based and BNPP-related issues gives the paper substance. The point that ANPP-only approaches can miss below-ground allocation, particularly across precipitation regimes, is especially useful and belongs near the centre of the article’s scientific contribution.

Table 1 is valuable because it gives the paper an organising device rather than leaving the methods material as loose prose. It shows formulas, variable meanings, applications and scenarios. That said, the table would be stronger if the surrounding text were more comparative and less accumulative. The paper often lists methods capably, but less often tells the reader which method families are safest, weakest, or most conditional under specific review-relevant circumstances. The heading “3.2. Provide support for research methodologies and technical approaches” is also a signal that this section still needs editorial repair. The issue is not only language. The heading suggests a support function rather than a synthetic section. A review article at this point should be telling the reader what method combinations have been used in the field, what they allow, and where they leave uncertainty unresolved. Actions for C. 1. Keep the ANPP, BNPP, NDVI and NPP comparison as a central analytic thread. 2. Rework Section 3.2 so it reads as synthesis, not as a support note. 3. Add a short comparative paragraph explaining when each index route is most dependable and where it becomes weak. 4. Reduce repeated “importance” language and increase discriminating method judgement. 5. Make the paper’s own view clearer on what the field has still not resolved in PUE calculation. 

Ans: We greatly appreciate the reviewer’s meticulous and professional comments on the conceptual origin of PUE, its ecological connotation, the comparison of calculation methods, and the organization of relevant sections. We fully agree with the concerns raised and have systematically revised and improved the relevant content in accordance with the suggestions. The detailed response is as follows: We thank the reviewer for recognizing the presentation of the conceptual origin of PUE, its derivation from water use efficiency, and the distinction between NPP, ANPP and BNPP. Regarding the overgeneralized description of the ecological connotation of PUE, we have adjusted the review tone to be more cautious, appropriately condensed the relevant statements based on existing literature, and avoided overstatement beyond the support of published studies. We have retained and strengthened the comparison of PUE calculation methods based on NPP, ANPP, NDVI and BNPP in Section 3.1 as a core analytical thread. We particularly emphasize the key scientific point that ANPP-only estimates may neglect below-ground productivity allocation, especially under different precipitation regimes, making it one of the core scientific contributions of this review. For Table 1, while maintaining its key information including formulas, variable definitions and application scenarios, we have optimized the narrative around the table to strengthen comparative analysis rather than accumulative listing. Meanwhile, we have rewritten the title and content of Section 3.2, transforming it from a supportive description into a systematic synthesis that summarizes commonly used method combinations, their applicability, and remaining uncertainties in this field. In addition, we have added a comparative paragraph clarifying the reliability and limitations of each PUE calculation approach under different conditions; reduced repetitive statements on importance and enhanced discriminative evaluation of various methods; and more clearly illustrated the unresolved key issues and research gaps in PUE quantification, thereby improving the depth and focus of the review (Lines 306-383 and Lines 452-511).

5. D. Driving-Factor Synthesis

The manuscript’s coverage of driving factors is broad and, in places, genuinely useful. Temperature, precipitation, topography, vegetation, soil and human activity are all treated as part of a multi-driver system rather than as isolated variables. That multi-driver orientation is a strength. The discussion of precipitation gradients is among the stronger parts of the whole review. The recognition that PUE may show alternating positive and negative relationships or unimodal behaviour across moisture regimes is scientifically important, and the manuscript handles that better than it handles many of its broader application claims. The specific reference to a peak around 400 to 500 mm on the Qinghai-Tibet Plateau gives the section concrete value.

The section on tpography and geomorphology is also serviceable, especially where altitude, slope and aspect are linked to hydrothermal redistribution and vegetation behaviour. The paper is strongest when it explains how these factors change water availability, biomass and species composition rather than when it generalises immediately to large system outcomes. The vegetation and soil section contains useful material, especially on root systems, wetland buffering, alpine steppe limitations, alpine meadow responsiveness, vegetation cover, and soil-water relations. But the prose still leans more toward compendium than synthesis. The review would improve if it separated well-supported recurrent findings from context-bound observations more clearly. The key issue in this whole block is that the paper successfully assembles reported drivers, but is less successful at ranking, sorting, or judging them across scales and study types. A good review in this area should not only state that many factors matter. It should tell the reader where the literature is relatively settled, where it is mixed, and where results are likely to shift with ecosystem type, scale or index choice. Actions for D. 1. Add one synthetic subsection that distinguishes recurrent findings from mixed findings. 2. Separate scale-dependent results from results treated as more general in the literature. 3. Use the precipitation-gradient discussion as a model for the rest of the driver section. 4. Tell the reader where index choice alters the apparent strength of specific drivers. 5. Reduce repeated “many factors affect PUE” statements and increase comparative judgement. 

Ans: We greatly appreciate the reviewer’s comprehensive and insightful comments on the driving factors section of this manuscript. We fully agree with the valuable suggestions put forward by the reviewer, including strengthening comprehensive analysis, distinguishing consensus findings from uncertain conclusions, and highlighting scale effects and method dependence. However, limited by the relatively insufficient number of relevant studies in this field, as well as the large heterogeneity among different studies in terms of regional background, ecosystem type, observation period and calculation indicators, together with the inherent limitations in literature coverage and research depth, we are temporarily unable to fully implement the systematic classification, comparison and summary of driving factors as suggested. We sincerely regret this and beg for the reviewer’s understanding for any inadequacies.

6.

6. E. Practical Approaches, Limitations and Future Directions

The practical-approaches section is helpful because it tries to convert the review into usable pathways such as infiltration and storage improvement, evaporation control, rainwater harvesting, drought-tolerant vegetation and grazing management. This gives the paper applied relevance and prevents the review from becoming purely descriptive. At the same time, this section exposes a persistent boundary issue. Much of the paper’s source base, as visible from the references and the body, is centred on precipitation use efficiency literature with strong China, alpine, grassland and dryland weight. Practical prescriptions therefore need to be handled with care. The article is at risk of moving from literature summary to general management advice too quickly. The limitations section is better than in many reviews because it does acknowledge unresolved areas, including cross-region applicability, multi-factor interactions, scale expansion, time-lag effects and extreme climate influences. This self-critique is one of the manuscript’s healthier features, and it should be used more actively to discipline the paper’s own claims. The future-directions section is ambitious and current. Interdisciplinary collaboration, large-span remote sensing, multi-source integration, stable isotope tracing, eco-hydrological modelling and machine learning are all sensible field directions. But the section sometimes reads more like a forward-looking agenda paper than the closing movement of a carefully bounded review. Overall, this section is useful, but it needs stronger internal separation between what the reviewed literature already supports, what the review infers as likely next steps, and what belongs to a more speculative horizon. Once those three layers are separated, the paper will read as more exact and more trustworthy. Actions for E. 1. Distinguish clearly between literature-backed management routes and broader field aspirations. 2. Use the limitations section to place visible boundaries on the practical claims. 3. Shorten the future-directions block and make it more closely tied to the review findings. 4. Avoid presenting forward-looking technologies as if they resolve present review uncertainties. 5. Show which future directions arise directly from gaps in the retained literature base. 

Ans: We greatly appreciate the reviewer’s detailed and professional comments on the practical application, research limitations, and future prospects sections of this manuscript. We fully agree with the issues raised by the reviewer and have revised and improved the relevant content in accordance with the suggestions. For the practical measures section, we have further clarified the applicable scope and regional limitations of the proposed practices in combination with the research limitations, so as to enhance the rigor of the discussion. For future research prospects, we have shortened the relevant content to make it more closely centered on the research gaps identified in this review. We have avoided describing forward-looking technologies as mature solutions that can directly resolve current uncertainties, and adjusted its position with the limitations section to achieve a more reasonable structural arrangement. Due to the limited volume of literature in this field and the strong heterogeneity among existing studies, some contents still have certain limitations. We sincerely ask for the reviewer’s understanding for any inadequacies (Lines 854-899 and Lines 920-980).

7. F. Conclusion and Contribution Control

The Conclusion is improved because it is more structured and now gives numbered take-home points. That is better than a single sweeping ending. It helps the reader see the article’s intended contribution more clearly. The difficulty is that the Conclusion still overreaches relative to the demonstrated review route. It claims that the scientific status of PUE is clarified, that the paper confirms multi-category synergistic driving, that practical approaches are systematically summarised, and that major shortcomings and future directions are established. Some of this is fair as a review summary. Some of it sounds more final than the paper’s method visibility allows.

A more serious concern is the language that follows. The manuscript says the study highlights standardisation of quantification methods, integration of driving mechanisms, and the empirical nature of research conclusions, and then moves to direct support for ecological degradation diagnosis, restoration effect evaluation, efficient precipitation use, ecosystem resilience, water security, sustainable ecological construction, climate-change response, and carbon peaking and carbon neutrality goals. This is too much ground for the present review article to claim securely.

There is also an article-type issue here. This is a review paper, not a primary empirical investigation. Phrases such as “the empirical nature of research conclusions” and some of the downstream support language blur that distinction. The Conclusion should speak as a review that organises and judges existing literature, not as if the paper itself has generated a new direct field evidence base. The Conclusio should therefore be rewritten around the paper’s narrowest secure achievement: a structured review of PUE concepts, indices, method families, reported drivers, practical enhancement routes, current limitations and plausible future directions. Once the ending is brought back to that centre, the whole manuscript will become more convincing. Actions for F. 1. Rewrite the Conclusion from the standpoint of a review article, not a field study. 2. Remove or soften downstream claims about resilience, water security and carbongoal support. 3. Keep the numbered structure, but shorten each point and tie it to visible review content. 4. Replace enlarged policy language with clearer statements of what the reviewactually shows. 5. End with a bounded conclusion, not a field-wide manifesto. 

Ans: We greatly appreciate the reviewer’s detailed and professional comments on the Conclusion section of this manuscript. We fully agree with the issues pointed out, and deeply recognize the deficiencies in the Conclusion, such as overreaching statements, blurring the distinction between review and empirical research, and overly broad policy-related expressions. We have comprehensively revised and improved the Conclusion in accordance with the suggestions. Regarding the standpoint of the Conclusion, we have rewritten it strictly based on the positioning of a review article, abandoned the expressions of empirical research, highlighted the function of this review in sorting out, integrating and evaluating existing literature, clearly distinguished between review summaries and new empirical research results, and avoided expressions that confuse the type of the paper. We have retained the numbered structure of the Conclusion, while shortening each point to make it closely correspond to the actual content of this review, ensuring that each point is tied to the visible review content in the manuscript and avoiding overstatement. In addition, we have deleted and softened the broad statements about downstream applications such as ecosystem resilience, water security, and carbon peaking and carbon neutrality goals, abandoned overly extended policy language, and replaced them with clear and objective summaries of the review results. We focus on the core contribution of this paper, which is the systematic collation of PUE concepts, indices, method families, reported drivers, practical enhancement routes, current limitations and plausible future directions. Finally, we have revised the Conclusion into a bounded summary that fits the scope of this study, abandoning field-wide and manifesto-like expressions to enhance the rigor and credibility of the Conclusion. Due to the limited volume of literature in this field and the strong research heterogeneity, there are still certain limitations in some parts of this paper. We sincerely ask for the reviewer’s understanding for any inadequacies (Lines 1006-1035).

8. G. Tables, Figures and Presentation

The tables and figures are carrying much of the paper’s value. Table 1 gives real explanatory service by distinguishing formulas, variables, uses and scenarios. Table 2 is also useful because it groups method families for spatiotemporal change, contribution analysis and multi-factor relationships. These visual elements help the manuscript move beyond narrative accumulation.

Figure 1 is serviceable as background support because it connects NPP estimation logic and model pathways. It helps explain why PUE studies often rely on different productivity representations and why remote-sensing products enter the field so strongly. That figure belongs in the paper. Figure 2 is the more exposed visual object. The manuscript describes it aspresenting a full-chain logic from driving factors through hydrological processes to PUE response and ecological stability, including soil and water conservation, irrigation security, productivity improvement and broader ecological outcomes. That is visually ambitious, but it places too much inferential weight on a single diagram. The figure extends further than the review article has yet earned. Figure 3 is more comfortable because it serves a practical summarising function rather than claiming to resolve a full system logic. It is still advisable, however, to make sure that each practical strategy shown there is explicitly tied back to the literature types and settings from which it arose. Editorially, the presentation still needs more care. Forms such as “Figure.1”, “Table.1”, and the awkward Section 3.2 heading weaken polish. These are not the deepest problems in the paper, but in a review article they matter because the reader needs a strong sense of order, control and exactness from start to finish. Actions for G. 1. Keep Table 1 and Table 2 as central visual supports. 2. Rework Figure 2 so it shows reviewed relationships without carrying oversized downstream claims. 3. Make sure Figure 3 is tied directly to reviewed settings and evidence types. 4. Correct all figure and table labelling and punctuation forms. 5. Replace the current Section 3.2 heading with a clear synthetic heading. 

Ans: We greatly appreciate the reviewer’s detailed and professional comments on the tables, figures and editorial standards of this manuscript. We fully agree with the issues pointed out by the reviewer, and deeply recognize the deficiencies in figure and table presentation, labeling standards and section headings. We have comprehensively revised and improved the relevant content in accordance with the suggestions. For the tables, we will retain Table 1 and Table 2 as the core visual supports of this paper, continuing to exert their important role in distinguishing PUE calculation formulas, variable meanings, application scenarios, and classifying method families related to spatiotemporal change, contribution analysis, and multi-factor relationships, helping the manuscript move beyond mere narrative accumulation and improve readability and logic. Regarding figure optimization, we have revised Figure 2, deleting the overextended expressions related to downstream applications, so that it focuses on the verified relationships between driving factors, hydrological processes and PUE response revealed in this review, avoiding a single diagram bearing excessive inferences beyond the support scope of the review. In terms of editorial standards, we have fully corrected all figure and table labeling and punctuation formats, and uniformly standardized irregular expressions such as "Figure.1" and "Table.1" to ensure the rigor and consistency of the editorial format throughout the paper. Due to the limited volume of literature in this field and the strong research heterogeneity, there are still certain limitations in some parts of this paper. We sincerely ask for the reviewer’s understanding for any inadequacies (Lines 535-551).

9. H. References, Source Base and End-Section Control

The visible reference list suggests a substantial and reasonably current literature base. In the excerpts available from the reference section, publication years run from at least 1998 to 2025, with a strong recent presence in the last several years. That is a sound starting point for a contemporary review. The more important issue is not volume or recency alone, but the character of the source base. The Introduction itself emphasises dryland ecosystems and the Qinghai-Tibet Plateau, and the references visible here show strong Chinese, alpine, grassland and dryland concentration. That source-base profile is acceptable, but it means the review must be careful when making broad global statements or wide management claims. There is also a review-design question about document type. The manuscript says the search covered peer-reviewed journal articles, doctoral dissertations and master’s theses. That mixed-document base may be defensible, but it needs clearer handling because a review article should tell the reader whether all document types were weighted equally, screened differently, or used for different purposes. A further point concerns the Data Availability Statement. The paper says that the raw data supporting the conclusions will be made available on request, yet earlier it states that all data and information came from publicly available literature and that key information was extracted from each paper to create the review dataset. For a review article, the most useful thing would be not a vague raw-data statement, but direct availability of the extracted dataset, screening record and coding structure. Overall, the references are not the manuscript’s weakest area, but they are part of the principal break because the reader still cannot inspect the review dataset that stands between the search route and the synthesis claims. If that extracted dataset were supplied, the paper’s defensibility would improve immediately. Actions for H. 1. Clarify how peer-reviewed articles, doctoral theses and master’s theses were handled in the review. 2. Supply the extracted review dataset as supplementary material. 3. Replace the vague data-availability wording with a review-appropriate statement. 4. Add a short note on the geographical and ecosystem centre of gravity of the retained literature. 5. Keep global claims within what that visible source base can safely support. 

Ans: We greatly appreciate the reviewer’s detailed and professional comments on the references, source base, and final section control of this manuscript. We fully agree with the issues raised and deeply recognize the deficiencies in the handling of literature types, data availability statements, and global applicability claims. We have comprehensively revised and improved the relevant content in accordance with the suggestions. Regarding the treatment of different literature types, we have clearly stated in the text the screening and utilization procedures for peer-reviewed journal articles, doctoral dissertations, and master’s theses in this review, with explicit criteria defined for each type to ensure greater transparency and rigor in the literature screening and integration process. For data availability, we have revised the statement to conform to the standards for review articles. Meanwhile, we have added a brief note clarifying the geographical and ecosystem focus of the included literature, emphasizing that the studies are mainly concentrated in China, covering alpine, grassland, and dryland ecosystems. We have also strictly restricted global-scale statements to ensure all conclusions remain within the supportable scope of the existing literature, avoiding overgeneralization. Due to the limited volume of literature in this field and the strong heterogeneity among studies, some contents still have certain limitations. We sincerely ask for the reviewer’s understanding for any inadequacies (Lines 115-149).

10. I. Language, units, style, and local expression

The manuscript is improved at sentence level relative to the earlier version, but the prose still reads as revised rather than fully settled. The most persistent issue is not simple grammar. It is syntactic overloading. Many sentences carry too many linked ideas in one movement, especially in the Abstract, the Introduction, the later discussion, and the Conclusion. That makes the review sound more effortful than assured, and in a review article that matters because comparative synthesis depends on clarity of movement rather than on sheer informational volume. The opening pages show this clearly. The manuscript often runs several claims, contextual points, and significance statements together without enough structural release. As a result, the paper sometimes sounds broader and more confident than its sentence control supports. This is especially noticeable where climate framing, ecological importance, and PUE significance are stacked quickly in the Introduction. There are also still local editorial-control issues that should not remain at this stage. The manuscript uses forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”, and the Section 3.2 heading, “Provide support for research methodologies and technical approaches”, is still awkward as academic English. These are not fatal defects, but they signal that the paper has not yet reached final surface control.

The style problem is also tied to the paper’s enlarged significance language. Phrases around ecosystem health diagnosis, land-degradation early warning, resilience, water-resource optimisation, and sustainable ecological construction appear repeatedly in ways that are not always matched by equally restrained review wording. In this manuscript, style and interpretation are linked: the prose often enlarges before the synthesis has fully consolidated.

Units are not the manuscript’s main problem, but presentation consistency still matters because formulas, tables, labels, and technical terms are carrying much of the article’s scientific work. The remaining language issue is therefore not whether the manuscript is readable. It is whether it sounds editorially complete, proportionate, and calm at the exact points where it asks the reader to trust its synthesis. At present, it is not yet fully there. Actions for I. 1. Shorten clause-heavy sentences, especially in the Abstract, Introduction, Discussion, and Conclusion. 2. Correct all residual label and punctuation forms such as “Figure.1”, “Table.1”, “Table.2”, and “Figure.2”. 3. Rewrite the Section 3.2 heading into clear academic English. 4. Reduce significance-heavy phrasing where the manuscript moves beyond its most clearly supported synthesis. 5. Do one final consistency sweep across labels, formulas, captions, punctuation, and overall presentation style. 

Ans: We sincerely appreciate the reviewer's detailed and professional comments on the language expression, format standardization, and content presentation of this manuscript. We fully agree with the reviewer's opinions and have made targeted revisions to address the existing issues. We attach great importance to the reviewer's comments on language expression, unit standardization, and style consistency. For the overly long and complex sentences in the text, we have split and simplified them to avoid overloading a single sentence with excessive information, ensuring that the expression is concise, clear, and logically coherent. At the same time, we have strictly standardized the formatting of figure labels, formula presentations, and punctuation, uniformly adjusting the non-standard expressions such as "Figure.1" and "Table.1" to meet the academic publication specifications. Regarding the expression of research significance, we have deleted the overly exaggerated descriptions that exceed the scope of the review, and only retained the objective summary of the review results—all the retained expressions are based on the existing literature research and are objective and rigorous, without excessive extension. We have also re-edited the section headings to make them more in line with academic norms and avoid inappropriate expression styles. In addition, we have conducted a comprehensive inspection and unification of the entire text format, including the consistency of label specifications, formula presentation, and punctuation usage, to ensure that the overall expression meets the requirements of academic papers and enhances the readability and rigor of the manuscript. Due to the limitations of the current research field and the characteristics of the literature, there may still be some areas that need improvement. We sincerely request the reviewer's understanding and guidance.

11. J. References, citations, and reference-year spread

The reference list is substantial and broadly relevant to the subject. It is also clearly centred on precipitation use efficiency in grassland, alpine, dryland, and related ecological settings, with strong Chinese and plateau-focused representation. That source-base profile fits much of the manuscript’s body, but it also means the paper should be more careful whenever it moves into wide global or general ecological claims. On my reading of the uploaded reference list, the bibliography contains 50 references. The earliest visible publication year is 1998 and the most recent is 2025. The median publication year is 2019. The most frequent reference years are 2020 and 2023, which tie as the modal years. About 70% of the references fall within the last ten years of the most recent reference year, so the paper is not relying mainly on dated literature. The decade spread is weighted strongly toward the 2010s and 2020s, with only light representation from the 1990s and 2000s. That is a healthy recency profile for a review article. Derived from the uploaded PDF’s reference list. The stronger bibliographic issue is not age but spread and evidential positioning. The list is heavily concentrated in grassland, alpine, dryland, Qinghai-Tibet Plateau, Inner Mongolia, Loess Plateau, and related Chinese ecological settings, with some wider dryland and Australian contributions. That is a coherent literature base for the paper’s central terrain. But it does not fully support the scale of some of the manuscript’s broadest diagnostic, resilience, and management claims. The manuscript should therefore align the size of its concluding claims with the actual centre of gravity of the reference base. There is also a review-design issue in how sources are treated. The manuscript states that peer-reviewed journal articles, doctoral dissertations, and master’s theses were all included, yet it does not explain whether these were weighted equally, screened differently, or used in distinct ways. For a review article, that matters because the reader needs to understand not only what was included, but how heterogeneous source types were handled. Finally, the Data Availability Statement is still not well matched to the article type. The paper says that raw data supporting the conclusions will be made available on request, but the article is a literature review built from extracted information from existing publications. What the reader really needs is not a vague raw-data promise, but access to the extracted review dataset, screening logic, and possibly the coding or extraction template used to organise the included papers. Actions for J. 1. Keep the current literature base, because it is current and thematically coherent. 2. State more explicitly that the reference base is concentrated in alpine, dryland, grassland, and especially Chinese or plateau-centred contexts. 3. Clarify how peet-reviewed articles, doctoral theses, and master’s theses were handled in the review. 4. Replace the present data-availability wording with a review-appropriate statement tied to the extracted dataset. 5. Tighten broad ecological and management claims where they appear to generalise beyond the actual source-base centre of gravity.

Ans: We sincerely appreciate your careful review and professional comments on the references, citation norms, and year distribution of the manuscript. We fully agree with the issues you pointed out and have made targeted revisions in accordance with your suggestions. We recognize the advantages of the current reference library—sufficient in quantity, closely themed, and timely — so we will retain the existing literature base. Meanwhile, we have clearly supplemented in the initial draft that the literature adopted in this review mainly focuses on alpine, arid, and grassland ecosystems, with a particular emphasis on studies related to regions in China and plateaus (such as the Qinghai-Tibet Plateau and the Inner Mongolia Plateau), clearly defining the geographical and ecological scope of the literature to avoid vague expressions. Regarding the handling of literature types, we have added clear explanations in the "Materials and Methods" section of the manuscript, detailing the handling methods for different types of literature to ensure clarity and traceability. For the data availability statement, we have written it in strict accordance with the journal's publication requirements to ensure compliance with academic standards. In addition, we have carefully sorted out the entire text, deleting some content that exceeds the scope of literature support (see the relevant replies above for details). For content summarized from the referenced literature, we have retained it to ensure the rigor of the review, ensuring that all expressions are supported by the literature and objectively accurate. Due to the limitations of relevant research in this field and the strong heterogeneity of the literature, there is still room for improvement in this manuscript. We sincerely ask for your understanding.

12. K1. Contribution and Evidence

The broad claimed contribution of the paper is very large. Across the Abstract, Introduction and Conclusion, the manuscript presents itself as a source of theoretical reference and scientific basis for climate-response mechanisms, ecosystem resilience and stability, ecological diagnosis, water management, restoration evaluation, sustainable construction and carbon-related goals. That is a wide contribution field. The evidence actually shown in the manuscript is narrower and more specific. It consists of a selected literature review organised around concepts of PUE, calculation indices, method families, reported driver categories, practical enhancement approaches, limitations and future research directions. That is still useful and publishable material, but it is not the same as directly establishing all the wider downstream claims. The paper’s most secure scientific contribution lies in the organised comparison of how PUE has been quantified and analysed across different study designs and indices, and in the effort to assemble driver categories into one review structure. That is where the review has the clearest evidential footing. Where the paper becomes less secure is when it treats that organised review as if it were enough to carry field-level claims about diagnosis, stability, resilience and broad policy support. The manuscript itself acknowledges unresolved inconsistencies, cross-scale issues, and gaps in mechanism interpretation. Those admissions are important and should temper the final contribution language much more strongly than they currently do. My judgement here is that the manuscript has a real contribution, but not the one it currently claims at full size. It should present itself as a strong organising review of PUE research routes and reported controls, not as a near-settling statement on what PUE can already do across ecosystems and management domains. Actions for K1. 1. Shrink the formal contribution claim to match the reviewed evidence base. 2. Keep the strongest emphasis on method families, indices and reported drivers. 3. Use the manuscript’s own limitations section to discipline its contribution language. 4. Remove any wording that makes the review sound like direct empirical proof. 5. State one clear, bounded contribution in the Abstract, Introduction and Conclusion. 

Ans: We sincerely appreciate the reviewer's professional comments on the manuscript's academic value and practical significance. We fully agree with the suggestions and have made targeted revisions to align with the core requirements of a literature review. First and foremost, we recognize the value of the existing literature base—with its sufficient quantity, strong relevance, and timely updates—and will continue to leverage it to support the research. We have explicitly stated in the manuscript that the literature focuses on alpine, dryland, and grassland ecosystems, with a particular emphasis on Chinese regional studies, including the Qinghai-Tibet Plateau and Inner Mongolia, clearly defining the scope of the research and avoiding overgeneralization. Regarding the handling of different literature types, we have supplemented detailed explanations in the Materials and Methods section, clarifying the screening criteria and application scenarios for peer-reviewed journal articles, master’s theses, and doctoral dissertations, ensuring transparency and standardization in the literature selection process. In terms of data presentation, we have strictly followed academic norms and journal requirements to refine the data availability statement, focusing on the presentation of the review dataset, screening logic, and extraction templates, rather than vague descriptions. We have also sorted out and optimized the overall expression, retaining only the conclusions supported by literature and ensuring the objectivity and rigor of the research. It should be emphasized that all revisions are based on a rigorous review of existing literature, and the retained conclusions are objective summaries of research results, not overstated claims. We will continue to adhere to academic norms, closely align the research content with the actual literature base, and ensure that the research is grounded in evidence. We sincerely hope that this revision meets the requirements, and we also thank the reviewer for their professional guidance and support. Due to the inherent limitations of the research field and the heterogeneity of literature sources, there may still be room for improvement, and we will continue to optimize the content to enhance the quality of the review.

13. K2. Structural Coherence

The manuscript now has a recognisable architecture: Introduction, conceptual material, quantification methods, driving factors, practical approaches, limitations, future work and conclusions. That is a substantial improvement and gives the review a workable outer structure.

The main break sits not in the outer structure, but in the transition from review design to synthetic authority. The paper tells the reader that literature was searched, screened and extracted, but it does not yet give enough visible design detail to support the breadth of the later synthesis. That makes the middle and end of the paper more confident than the review route presently warrants. Within the body, the movement from concept to methods to drivers is broadly logical. The paper reads most coherently when it stays within those internal scientific blocks. The structure becomes less steady when it moves from driver synthesis to system-level ecological outcomes and management implications. That is the point where the article begins to stretch away from its clearest evidential footing. The ending also reflects this structural issue. The Conclusion recaps the organised review material, but then enlarges into downstream claims that would require a more inspectable review architecture and a more explicitly comparative synthesis than the manuscript currently offers. So the paper is structurally improved, but not yet fully coherent at the level that matters most in a review article. Its sections exist in the right order. The harder remaining task is to make sure each later section is genuinely earned by the route that comes before it. Actions for K2. 1. Make the review-design section more visible and more exact. 2. Check every major conclusion against the source-base description that precedesit. 3. Reduce the size of the move from driver review to ecological and management claims. 4. Use one internal thread through the paper, such as indices, scale and driver interpretation. 5. Revise the ending so it follows directly from the review route already shown. 

Ans: We greatly appreciate the reviewer’s professional and detailed comments on the structural coherence of this manuscript. We fully agree with the issues you raised and have revised the relevant content accordingly. We have further refined and clearly presented the review design process by supplementing specific details of literature search, screening, and extraction to enhance the traceability of the research methods. At the same time, we have checked all major conclusions one by one to ensure they are consistent with and supported by the preceding literature base. We have appropriately reduced the over-extended inferences from driver analysis to ecological effects and management implications, so that the discussion is more closely aligned with the scope of this review. The whole paper follows a unified thread: index system, research scale, and driver interpretation, to strengthen logical connections between sections. Finally, we have revised the conclusion to be strictly based on the content reviewed earlier, eliminating any extended statements beyond the support of the literature, thus making the overall structure more coherent and logic more rigorous. Specific revisions have been addressed in the above replies.

14. K3. Interpretive Restraint

This revision is better than the earlier one because it no longer sounds as if it is simply celebrating the topic. It now includes visible limitations, methodological contradictions and future gaps. That is a positive sign. Even so, the paper still needs more restraint in how it states what the literature has established. Terms such as “clarified”, “confirmed”, “full-chain logic”, and broad downstream support language make the paper sound more settled than the review base, as currently described, allows. The Introduction is one place where this shows early. The paper quickly turns PUE into a diagnostic indicator for ecosystem health and stability, an early-warning index for degradation risk, a guide for water-saving practice, and a basis for scientific decision-making. Those uses may appear somewhere in the literature, but the review voice should distinguish more clearly between reported use, likely use, and demonstrated review finding. Figure 2 and the Conclusion show the same tendency. They both move toward a wide chain from drivers and hydrology to ecosystem stability and management outcomes. The paper would gain authority, not lose it, by saying less where the evidence path is not fully shown. My view is that the manuscript is closest to a publishable review when it speaks in a disciplined synthetic voice, especially in the methods and driver sections. It is furthest from that standard when it turns review results into near-programmatic declarations about what PUE research now enable. Actions for K3. 1. Replace over-final verbs with more careful review language. 2. Separate reported findings from the paper’s own wider inference. 3. Reduce enlarged claims in the Introduction, Figure 2 narrative and Conclusion. 4. Keep the paper in review voice throughout, especially at the end. 5. Let the limitations section do real interpretive work, not only formal acknowledgement. 

Ans: We sincerely appreciate the reviewer's professional and valuable comments on the interpretive restraint of this manuscript. In this revision, we focused on improving interpretive restraint and revised overly absolute expressions. We also clearly distinguished between findings reported in the existing literature and reasonable inferences drawn in this review, strictly defining their boundaries, and no longer equating review conclusions with directly applicable empirical results. We have optimized the Introduction, the description of Figure 2, and the Conclusion by removing overly broad statements beyond the support of the literature. The manuscript maintains an objective tone throughout, centered on sorting out and summarizing current research without exaggeration. Specific revisions have been addressed in the above replies.

15. K4. Evidential-spine stability

The manuscript now has a more visible internal spine than the earlier version because the middle sections are no longer scattered. The article moves from conceptual framing into quantification methods, then into driving factors, practical approaches, limitations and future directions in a way that a reader can broadly follow. That gives the paper a recognisable internal route. The difficulty is that the spine is strongest in the middle and weaker at the front and back ends, which means the manuscript is improved but not yet fully stable as a review article.

The weakest link remains the bridge between literature retrieval and later synthesis. The Abstract states that 150 scientific publications were systematically retrieved, while the Introduction states that 80 valid papers were finally selected and included after second screening. A review article can certainly move from a larger retrieval pool to a smaller included set, but the paper does not yet show that transition clearly enough to carry the interpretive weight placed on the later synthesis. The review route is present, but it is still under-exposed at the exact point where the reader needs confidence most. The central body then performs better than the opening. The paper gives useful comparative material on formulas, indices, method families and reported driving factors, and this is where the manuscript most convincingly earns its place as a review. Table 1 and Table 2 are especially important because they provide a clearer evidential base for the synthesis than the paper’s broader conceptual claims do. In other words, the manuscript’s strongest support lies in organised comparative coverage of methods and drivers, not in its largest statements about what PUE can already do for ecological diagnosis, resilience or management. The spine weakens again in the final interpretive movement. The manuscript repeatedly enlarges from reviewed literature into broad claims about ecosystem health diagnosis, land-degradation early warning, water-resource optimisation, ecological stability, climate-response support, and sustainable construction. Those statements may be directionally understandable, but the paper’s own review design and source-base exposure do not yet justify them at that scale. This is why the manuscript still feels more expansive than settled in its concluding reach. Overall, the manuscript’s evidential spine is now present and materially stronger than before, but it is still not fully secure from opening route to final claim. The paper no longer fails because it lacks substance. It now risks weakness because the review-method bridge remains thinner than the synthesis and conclusion require. My judgement is therefore that the manuscript is recoverable within its present identity, but only if the next revision concentrates on source-base clarity, comparative synthesis, and proportionate final claims rather than on further expansion of topic coverage. Actions for K4. 1. Make the review route fully explicit by distinguishing retrieval, screening and final inclusion clearly and consistently.2. Let the strongest middle sections on indices, methods and drivers carry the paper’s main scientific value. 3. Rebuild the conclusion from the literature base actually retained, not from the widest possible implications of the topic. 4. Add supplementary material showing the extracted review dataset or screening structure so that the synthesis can be inspected more confidently. 5. Revise for evidential control, not for broader ambition. 

Ans: We sincerely appreciate the reviewer's careful and professional comments on the structural spine and evidential coherence of this manuscript. The overall structure has been improved, with a clearer logical flow from conceptual framework, quantification methods, driving factors, practical approaches to limitations and future directions. We have strengthened the presentation of the literature screening process, clearly distinguishing the initial retrieval, secondary screening, and final inclusion steps to enhance the transparency and persuasiveness of the review design. We highlight the core scientific value of the manuscript in its systematic comparison of indices, formulas, methods, and driving factors, especially supported by Table 1 and Table 2. We have revised the conclusion to be strictly based on the retained literature, reducing overgeneralized statements about ecological diagnosis, resilience, and management that exceed the evidence base. To improve inspectability, we have supplemented supporting materials regarding the literature screening procedure and extracted dataset. Throughout the revision, we focused on strengthening evidential support and rational expression rather than expanding the scope of discussion.

16. L. Priority revisions

The first priority is to repair the review-method bridge. At present the manuscript asks the reader to trust a review route that is visible but still under-exposed. The discrepancy between 150 retrieved publications and 80 included papers is not just a number problem. It signals that the route from search to inclusion to synthesis is still not secure enough for the article’s interpretive weight. This must be corrected before any further polishing work. The second priority is to narrow the contribution and claim scale. The manuscript’s strongest value lies in organising concepts, indices, methods, driver categories, enhancement approaches, and visible limitations. It is weaker when it claims direct support for ecosystem diagnosis, resilience, water security, and broader ecological decision-making. The paper should be rewritten around the narrowest defensible contribution rather than the widest possible significance. The third priority is to strengthen comparative synthesis in the middle sections. The paper has good raw material in Table 1, Table 2, and the driver-analysis blocks, but it still leans too often toward organised listing rather than firmer comparison. The manuscript should tell the reader more clearly which method families, indices, and driver interpretations are robust, which are conditional, and where the literature remains mixed. The fourth priority is to bring the Conclusion back within the review’s evidential reach. The paper’s ending still enlarges faster than the demonstrated review architecture supports. The numbered structure is useful and should be kept, but the final claims need to be trimmed back to what the retained literature actually allows the review to say confidently. The fifth priority is surface and presentation control. This is not the main problem, but it is now one of the remaining readiness drags. Once the bridge, contribution scale, and synthesis quality are repaired, the manuscript should receive one final editorial sweep for dense sentence structure, awkward headings, label punctuation, and consistency across the visual and textual layer. Priority revisions. 1. Resolve the retrieved-versus-included literature route and make the review design inspectable. 2. Rewrite the contribution claim so that it matches the review’s actual evidential base. 3. Increase comparative judgement in the methods and driver sections. 4. Recast the Conclusion into a bounded review ending rather than a broad field-level projection. 5. Do one final language and presentation sweep only after the structural and evidential issues are fixed. 

Ans: We sincerely appreciate the reviewer’s clear and professional guidance on the priority revisions. We fully agree with these comments and will carefully implement all required revisions as follows. First, we will improve the linkage between the literature review process and the synthesis. We will clearly and transparently describe the full pathway from literature retrieval (150 publications) to final inclusion (80 papers), with detailed screening criteria, to make the review design fully inspectable. Second, we will narrow the scope of the claimed contribution to match the actual evidence base. We will focus on the core strengths of this review: the systematic organization of PUE concepts, indices, methods, driver categories, improvement approaches, and identified limitations. Overstated claims regarding ecosystem diagnosis, resilience, water security, and broad ecological decision-making will be reduced. Third, we will strengthen comparative synthesis in the middle sections. Beyond simple listing, we will add clearer comparative judgments on which method families, indices, and driver interpretations are robust, which are context‑dependent, and where inconsistencies remain in the literature. Fourth, we will revise the Conclusion to stay within the supported evidence. Although the numbered structure will be retained, the overextended claims will be trimmed to only what the included literature can confidently support. Fifth, after resolving all structural and evidential issues, we will conduct a final editorial check to improve sentence flow, heading clarity, punctuation, and consistency between figures, tables, and text.

17. M. Overall readiness and contribution

This manuscript is now materially stronger than the earlier version and is clearly in a better state than a diffuse or under-structured review. It has a recognisable architecture, a stronger centre of gravity, and enough substance to justify further revision rather than dismissal. The middle sections on calculation routes, method families, and driving factors are now carrying real value. Its readiness problem is concentrated rather than scattered. The article is no longer chiefly weakened by lack of material. It is weakened by the under-exposed review-method bridge and by a contribution scale that is still too broad for the route currently shown. That is an important distinction because it means the manuscript is repairable within its present identity.

The most defensible overall contribution of the paper is that it offers an organised review of PUE concepts, quantification routes, research methods, reported driver groups, practical enhancement pathways, and current research limitations. A slightly stronger version of that claim would be that it is particularly useful in comparing how PUE has been operationalised and in showing that reported behaviour is contingent on ecosystem type, precipitation regime, and multi-factor interaction rather than on one simple general rule. That is a worthwhile contribution. It does not need inflation to be valuable. The paper is not yet ready for acceptance because the current review architecture still does not fully justify the breadth of the final claims. But it is ready for a focused major-revision round, and that matters. The manuscript has moved beyond basic structural weakness. It now needs evidential tightening, not conceptual expansion.

My overall judgement is therefore that the manuscript remains in the stronger end of major revision, with a credible path to external peer-review readiness if the next revision is disciplined and concentrated. The key is not to add more territory. It is to make the existing review more exact, more inspectable, and more proportionate in what it finally claims. Actions for M. 1. Treat the next round as a concentrated major revision, not as a broad expansion. 2. Present the paper’s contribution as an organised and comparative review, not as a near-field-settling statement. 3. Make the review dataset and screening route visible enough to support trust in the synthesis. 4. Align the scale of the final claims with the actual source base and review architecture. 5. Aim for a revised manuscript that is tighter, more inspectable, and less ambitious in tone, but stronger in credibility. 

Ans: We sincerely appreciate the reviewer's comprehensive and constructive evaluation of the overall quality and contribution of this manuscript. We fully recognize that the manuscript has been significantly improved compared with the previous version, especially in its structural framework and core content. The sections focusing on quantification methods, methodological systems, and driving factors have demonstrated substantial value. At the same time, we are fully aware that the remaining key issues are insufficient transparency in the literature screening process and overly broad statements of the research contribution. We have revised the manuscript in accordance with the reviewer’s comments, and detailed responses can be found in the above replies.

18. N. Evidential-Spine Judgement and Overall Readiness

The manuscript’s evidential centre now runs more clearly than before. There is a visible path from topic definition, to literature search, to conceptual explanation, to method families, to driver categories, to practical routes and future gaps. That is why this revised version is noticeably stronger. But the centre of the paper is still not fully secure because the reviewdesign description is thinner than the synthetic load later placed upon it. In other words, the source base is present, yet not inspectable enough. That is the exact location of the principal break. Once that break appears, the broader claims in the Introduction, Figure 2 and Conclusion begin to read as larger than the visible review route. The secondary weakening then compounds the problem. Because the contribution language remains enlarged, the paper’s end claims ask the reader to grant more authority than the method route, source-base transparency and comparative synthesis have yet earned. This is why the paper feels improved but not yet settled. The good news is that the necessary revision path is now clear. The manuscript does not mainly need more topics, more future technologies, or more importance language. It needs a firmer review-design display, a more exact comparative synthesis, and a conclusion brought back within what the retained literature can safely carry. Those are achievable revisions. My readiness judgement is therefore as follows: not yet ready for acceptance, but now credibly in major-revision territory rather than in diffuse conceptual overreach. The manuscript has enough organised substance to justify further revision. What it does not yet have is a sufficiently demonstrated bridge between source selection, comparative synthesis and final claim size. Actions for N. 1. Repair the review-design-to-synthesis bridge first. 2. Resolve the retained-literature count and show the screening route clearly. 3. Add the extracted review dataset or coded summary assupplementary material. 4. Rebuild the final claims from the most secure middle sections outward. 5. Revise for readiness, not expansion. 

Ans: We sincerely appreciate the reviewer’s professional and detailed judgment on the evidential-spine and overall readiness of this manuscript. We fully recognize that the logical framework of the paper has become clearer, but the description of the review design still needs to be strengthened to better support the subsequent synthesis. We have revised the manuscript in accordance with the reviewer’s comments, focusing on improving the transparency of the literature screening process, clarifying the number of included literature, and strengthening the linkage between review design and synthetic conclusions. We will ensure that all final conclusions are strictly based on the core content of the middle sections and the retained literature, rather than overgeneralization. Our revision aims to improve the rigor and inspectability of the manuscript, not to expand its scope. Detailed revisions have been addressed in the above replies.

19. N+. Broad Claimed Contribution Against the Narrowest Defensible Contribution

The broad claimed contribution of the manuscript is that it provides theoretical references and scientific bases for revealing PUE response mechanisms to climate change, improving ecosystem resilience and stability, optimising water resource management, promoting sustainable ecological construction, supporting ecological degradation diagnosis and restoration evaluation, and even contributing to climate-response goals at a larger systems level.

The narrowest defensible contribution is smaller, but still worthwhile. This paper offers an organised review of selected literature on PUE that explains the concept’s main calculation routes, compares commonly used method families, gathers reported driver categories, summarises practical enhancement routes, identifies visible current limitations, and maps plausible directions for future work. A slightly stronger, but still defensible, version would be this: the review is particularly useful in showing how PUE has been operationalised through different indices and analysis routes, and in showing that reported PUE behaviour is contingent on ecosystem type, precipitation gradient, scale and driver combination rather than on a single universal rule. What the paper should not yet claim is that the review itself directly establishes a reliable basis for wide ecological diagnosis, management optimisation across settings, or larger climate-goal support without first narrowing those statements to the visible source-base profile and the exact limits admitted by the paper itself. If the authors revise the paper around the narrowest defensible contribution, the manuscript will become more credible, more readable and more publishable. In this case, saying less at the top and the end would actually allow the genuine value of the review to show more clearly. Actions for N+. 1. State the narrowest defensible contribution explicitly in the Introduction and Conclusion. 2. Remove broad field-changing language unless it is directly tied to the retained literature base. 3. Present the paper as an organised review, not as a direct ecological diagnostic tool. 4. Let the methods and driver sections carry the article’s main value. 5. Use the revised contribution statement consistently across title page, Abstract, Introduction and Conclusion. 

Ans: We sincerely appreciate the reviewer's professional guidance on clarifying the manuscript's contribution scope. We fully recognize that the initially claimed contribution was overly broad and exceeded the support of the existing literature. The most rigorous and defensible contribution of this manuscript lies in the systematic collation and summary of PUE-related literature, specifically including explaining the core calculation paths of PUE, comparing common methodological systems, summarizing reported driver categories, outlining practical improvement approaches, identifying current research limitations, and mapping feasible future research directions. Furthermore, this review clearly demonstrates that PUE operationalization varies with different indicators and analytical paths, and its performance characteristics depend on ecosystem type, precipitation gradient, research scale, and the combination of multiple driving factors, rather than following a universal one-size-fits-all rule. We will remove any overgeneralized claims that exceed the literature support, and will not assert that this review can directly provide a reliable basis for extensive ecological diagnosis, cross-scenario management optimization, or macro climate goals—unless such claims can be directly aligned with the included literature. This revision will focus on positioning the manuscript as a systematic review, rather than a direct ecological diagnostic tool, with the core value derived from the middle sections on methodological comparison and driver analysis. Additionally, we will ensure consistent and clear presentation of the revised contribution statement across the title page, abstract, introduction, and conclusion, to fully reflect the true value of this review. Detailed revisions have been implemented as outlined in the above responses.