Development of Polymorphic Index Model for Assessing Subtropical Secondary Natural Oak Forest Site Quality Under Complex Site and Climate Variables

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The text "A Polymorphic Site Index Model for Subtropical Oak Natural Secondary Forests Based on Site, Climate, and Their Interactions" is organized correctly, and all sections effectively describe the research goal established by the authors. The idea of the text is based on a straightforward assumption: to find the best model to determine the site index based on the surface and climate factors. The experiment was realized on the base of 101 sample plots located in Hunan Province in China.

I'm impressed by the author's modelling skills. The methodology is planned very well and represents classical approaches in modelling. An interesting clustering method was implemented to find the best model. I have no comments on this section – it is very good. I'm interested in the actual number of trees used in the research. All we know is that there were 101 sample plots with a size of 20x30 meters.

In practice, the only serious concern I have touched on is the matter of the primary goal. You have mentioned that it is a natural secondary forest. So, if it is natural - can the results of this research help in the future? We do not know if there is any idea of silviculture in this area. Will it still be natural or not? I mean that any academic deliberating on the phenomena which, in practice, we cannot change is useless. It is only an idea. Additionally, the authors mentioned that slope and aspect have an impact, elevation is significant, and climate variable has a big impact. I definitely agree, but what can you do with this knowledge? These are stable factors that no one can change. So again, what would the practice sound of this research be if we talk about unchanged factors in natural forests? Your results should be supported somehow in the discussion and conclusion of the actual implementation of the developed model. In practice, I found one sentence that can explain the need: "Effective management of this regional-scale distribution of tree species requires an accurate site quality assessment," but that is all. Once again, I remind you it is a natural forest, and all the factors do not depend on humans.

Some additional comments on the original paper's line number are below.

 

"Additionally, in each sample plot, site factors such as elevation, slope, slope aspect, slope position, soil type, and soil depth were recorded". Please add a detailed description of how exactly it was measured and recorded.

"Table 1 contains the descriptive statistics pertaining to the dominant trees and site factors." Do not write such a sentence in the text. This is the title of the table, so it should be there, not in the text.

"using ClimateAP" – let readers know some details about it.

Slope aspect – Please explain the range of direction for the defined slope aspect variable.

Author Response

Comments and Suggestions for Authors

The text "A Polymorphic Site Index Model for Subtropical Oak Natural Secondary Forests Based on Site, Climate, and Their Interactions" is organized correctly, and all sections effectively describe the research goal established by the authors. The idea of the text is based on a straightforward assumption: to find the best model to determine the site index based on the surface and climate factors. The experiment was realized on the base of 101 sample plots located in Hunan Province in China.

Response: Thank you for your comment.

I'm impressed by the author's modelling skills. The methodology is planned very well and represents classical approaches in modelling. An interesting clustering method was implemented to find the best model. I have no comments on this section – it is very good. I'm interested in the actual number of trees used in the research. All we know is that there were 101 sample plots with a size of 20x30 meters.

Response: Thank you for your comment. The stand densities of the sample plots in our study area ranged from 722 to 4118 trees/ha, totalling 9260 trees. L154-155

 

In practice, the only serious concern I have touched on is the matter of the primary goal. You have mentioned that it is a natural secondary forest. So, if it is natural - can the results of this research help in the future? We do not know if there is any idea of silviculture in this area. Will it still be natural or not? I mean that any academic deliberating on the phenomena which, in practice, we cannot change is useless. It is only an idea. Additionally, the authors mentioned that slope and aspect have an impact, elevation is significant, and climate variable has a big impact. I definitely agree, but what can you do with this knowledge? These are stable factors that no one can change. So again, what would the practice sound of this research be if we talk about unchanged factors in natural forests? Your results should be supported somehow in the discussion and conclusion of the actual implementation of the developed model. In practice, I found one sentence that can explain the need: "Effective management of this regional-scale distribution of tree species requires an accurate site quality assessment," but that is all. Once again, I remind you it is a natural forest, and all the factors do not depend on humans.

Response: While certain characteristics of natural secondary forests, such as slope, aspect, and elevation, are stable, understanding how these factors influence forest growth is crucial for developing future management strategies. This research provides a framework to help forest managers make strategic plans, adaptive management, and protect areas with special ecological value without altering the natural conditions. Moreover, the significant impact of climate variables on forest growth emphasizes the need for adaptive strategies to cope with climate change. The model developed in the study can serve as a decision-support tool for management tailored to specific sites, optimize resource allocation, and continuously monitor forest health. Although these factors are stable, the knowledge gained from this research can help shape the future of forests, providing a scientific basis for sustainable forest management in response to environmental changes and growing demands on forest resources.Future research can further explore how to integrate these findings into specific management plans, including conducting economic analyses of different management strategies and studying the social and ecological impacts of implementing these strategies. In short, this study provides a scientific foundation for action to address environmental changes and the needs of forest resources.

 

Some additional comments on the original paper's line number are below.

"Additionally, in each sample plot, site factors such as elevation, slope, slope aspect, slope position, soil type, and soil depth were recorded". Please add a detailed description of how exactly it was measured and recorded.

Response: Our sample plot data came from the same subject group, so our data measurement tools were the same [50]. It is cited in our manuscript [50]. The details are as follows:

You, W.; Zhu, G. The Minimum Target Diameter and the Harvest Age of Oak Natural Secondary Forests in Different Sites Conditions: Case Study in Hunan Province, China. Forests 2024, 15, 120.

Elevation was measured by a Real-Time Kinematic Surveyor (SR6 Plus) manufactured from Qianxun SI (Shanghai, China), slope and aspect were measured by a laser compass meter (DQL-16ZJ) from Harbin Optical Instrument Factory (Harbin, China), soil type and slope position were obtained from forest history data provided by local forestry centers, soil depth was obtained by measuring the distance from the rock to the soil surface with a straightedge, DBH was measured by a diameter tape and tree height was measured by a laser rangefinder (TruPulse 200) from Laser Technology (Asia) Ltd. (Guangzhou, China). The specific survey method refers to the National Standards of the People’s Republic of China “Technical regulations for continuous forest inventory”.

"Table 1 contains the descriptive statistics pertaining to the dominant trees and site factors." Do not write such a sentence in the text. This is the title of the table, so it should be there, not in the text.

Response: Thank you for your corrections. We have deleted these sentences.

"using ClimateAP" – let readers know some details about it.

Response: Thank you for your corrections. ClimateAP is a stand-alone Windows application developed and maintained by the University of British Columbia (UBC) that allows us to spatially interpolate climate models to obtain annual, seasonal, and monthly climate variables by simply providing the latitude, longitude, and elevation of the sample site. Our manuscript mentions " Climate variables in each plot were obtained using ClimateAP [56] through spatial interpolated estimation based on latitude, longitude, and elevation [57]".

56. Wang, T.; Hamann, A.; Spittlehouse, D.L.; Murdock, T.Q. ClimateWNA—High-Resolution Spatial Climate Data for Western North America. Journal of Applied Meteorology and Climatology 2012, 51, 16–29.
57. Zhang, X.; Wang, Z.; Chhin, S.; Wang, H.; Duan, A.; Zhang, J. Relative Contributions of Competition, Stand Structure, Age, and Climate Factors to Tree Mortality of Chinese Fir Plantations: Long-Term Spacing Trials in Southern China. Forest Ecology and Management 2020, 465, 118103.

Slope aspect – Please explain the range of direction for the defined slope aspect variable.

Response: Thank you for your suggestion. We have made the following changes in the article.

Note: The range of shady slope, semi-shady slope, semi-sunny slope, and sunny slope is as follows: 0° to 45°, 45° to 135°, 225° to 315°, and 315° to 360°, sequenced in that order. Table 3.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Title.

The title could be revised to reflect the study's results, for example, “Polymorphic subtropical secondary natural oak forest site index model for estimating forest productivity under complex site and climate variables. It can also be revised to “Potential of polymorphic subtropical secondary natural oak forest site index model for estimating forest productivity under complex site and climate variables” or “Development of polymorphic index model for assessing subtropical secondary natural oak forest site quality under complex site and climate variables” or “Development of polymorphic models for assessing environmental factors affecting subtropical secondary natural oak forest site index under complex site and climate variables” or “Modelling method (approach) for predicting (assessing) subtropical secondary natural oak forest site index under complex site and climate variables” or “Assessing environmental factors affecting subtropical secondary natural oak forest site index using a polymorphic model”. However, the proposed titles are applicable if the results can prove them. (The authors have indicated at the abstract's end or Line 524-525 that the results could confirm that. Moreover, the authors devoted the discussion section to explaining the main environmental factors affecting the site index. They also used the word “developed” in Line 527 in the conclusion section).

 

Abstract.

Line 9-10. Probably revise it to “Site and climate conditions are the key determinants controlling dominant height growth and forest productivity, both independently and interactively”.

Line 10-11. This may be revised to “Secondary natural oak forests are typical forest type in China, especially in Hunan Province, but little is known about the site index of this forest under the complex site and climate variables in the subtropics”.

 

Line 12. The first section of the sentence can be revised to “Based on survey data of dominant trees and site variables from 101 plots in Hunan oak natural secondary forests and climate data obtained using spatial interpolation, we…”. 

 

Line 16. The first part of the sentence can be revised to “Of the site variables, elevation affected stand dominance the most, followed…”.

 

Line 18. The sentence can be revised to “To develop the modelling method, we…models, but found…”

 

Line 28-29. Although a site index can be used to estimate site productivity, no estimate of forest productivity was presented or evaluated in the study. Thus, the study did not prove the point stated in the sentence. Probably revise the sentence to “The modelling method developed in this study could be used to assess regional secondary natural oak forest site index under complex site and climate variables to evaluate the forest productivity”.

 

Introduction.

Line 75. Please start a new paragraph for “Like other environmental…”

 

Line 87. The first sentence is redundant, so please delete it or place it in a more suitable position in the paragraph.

 

Line 106. Please revise the end of the sentence to “… factors with climate factors for secondary natural oak forests”.

 

Line 95-106. This paragraph can be organised and improved by smoothing the transition of points between sentences, enhancing connectivity, and elucidating the study's central idea.

 

Line 108. For the second objective, isn’t “to evaluate” a better word to describe the work than “to measure”?

 

Materials and Methods.

Line 233. The model was fitted using the entire dataset. Is that better than fitting the model on half or 75% of the data and validating it using the remaining data? Is there any evidence that the former is better than the latter?

 

Is there a subtopic explaining the process/analysis of finding the answer for the second aim of the study?

 

Results.

Line 250. Please name the subtopic to reflect the study's first aim, for example, “3.1 Factors affecting growth and growth responses”.

 

Please create a new subtopic to indicate the findings for the second aim, such as “3.2 Impacts of site and climatic factors on dominant height.”

 

(Since the rest of the results, starting from Section 3.2, are associated with the third aim).

 

Were oak species included in the data analysis? What was the finding?

 

Discussion.

Please clearly indicate the discussion for each aim of the study. Separate them into three subtopics.

 

Can Figure 7 (and the associated explanation or description) be placed under Results? Also, for Figure 7, the legend is probably optional (can be deleted), or the acronyms are spelt out. 

 

Was oak species a critical factor affecting the site index of the studied forest?

 

Lines 522-525. If this is one of the study's conclusions, please state it under Conclusions.

 

Conclusions.

Please organise the conclusion to reflect the study's three aims clearly.

 

Lines 542-545. The sentence can probably be revised: “The study showed that our site index modelling method (approach) could offer valuable insights for subtropical secondary natural oak forest management under complex site and climatic conditions. Additionally, it can potentially be used to predict (assess) precisely the regional secondary natural oak forest site index and productivity in the face of future climate change.”

 

Comments on the Quality of English Language

Minor editorial work is required to simplify some of the sentences or to smoothen the transition of points between sentences.

Author Response

Comments and Suggestions for Authors

Response: Thank you for your careful review of our manuscript. Based on your suggestions, we have further enhanced the manuscript for revision.

 

1.Title.

 

The title could be revised to reflect the study's results, for example, “Polymorphic subtropical secondary natural oak forest site index model for estimating forest productivity under complex site and climate variables. It can also be revised to “Potential of polymorphic subtropical secondary natural oak forest site index model for estimating forest productivity under complex site and climate variables” or “Development of polymorphic index model for assessing subtropical secondary natural oak forest site quality under complex site and climate variables” or “Development of polymorphic models for assessing environmental factors affecting subtropical secondary natural oak forest site index under complex site and climate variables” or “Modelling method (approach) for predicting (assessing) subtropical secondary natural oak forest site index under complex site and climate variables” or “Assessing environmental factors affecting subtropical secondary natural oak forest site index using a polymorphic model”. However, the proposed titles are applicable if the results can prove them. (The authors have indicated at the abstract's end or Line 524-525 that the results could confirm that. Moreover, the authors devoted the discussion section to explaining the main environmental factors affecting the site index. They also used the word “developed” in Line 527 in the conclusion section).

Response: In accordance with your suggestion we have changed the title from " A Polymorphic Site Index Model for Subtropical Oak Natural Secondary Forests Based on Site, Climate, and Their Interac-tions" to " Development of Polymorphic Index Model for assessing Sub-tropical Secondary Natural Oak Forest Site Quality under Complex Site and Climate Variables ".

 

2.Abstract.

 

Line 9-10. Probably revise it to “Site and climate conditions are the key determinants controlling dominant height growth and forest productivity, both independently and interactively”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

Site and climate conditions are the key determinants controlling dominant height growth and for-est productivity, both independently and interactively. L11-12

 

Line 10-11. This may be revised to “Secondary natural oak forests are typical forest type in China, especially in Hunan Province, but little is known about the site index of this forest under the complex site and climate variables in the subtropics”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

Secondary natural oak forests are typical forest type in China, especially in Hunan Province, but little is known about the site index of this forest under the complex site and climate variables in the subtropics. L13-15

 

Line 12. The first section of the sentence can be revised to “Based on survey data of dominant trees and site variables from 101 plots in Hunan oak natural secondary forests and climate data obtained using spatial interpolation, we…”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

Based on survey data of dominant trees and site variables from 101 plots in Hunan oak natural secondary forests and climate data obtained using spatial interpolation, …L17-19

 

Line 16. The first part of the sentence can be revised to “Of the site variables, elevation affected stand dominance the most, followed…”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

Of the site variables, elevation affected stand dominant height the most, …L23-24

 

 

Line 18. The sentence can be revised to “To develop the modelling method, we…models, but found…”

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

To develop the modelling method, …but …L26-27

 

Line 28-29. Although a site index can be used to estimate site productivity, no estimate of forest productivity was presented or evaluated in the study. Thus, the study did not prove the point stated in the sentence. Probably revise the sentence to “The modelling method developed in this study could be used to assess regional secondary natural oak forest site index under complex site and climate variables to evaluate the forest productivity”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

The modelling method developed in this study could be used to assess regional secondary natural oak forest site index under complex site and climate variables to evaluate the forest productivity. L36-38

 

3.Introduction.

 

Line 75. Please start a new paragraph for “Like other environmental…”

Response: Thank you for your advice. We have made the changes in the revised draft as you suggested.

L86-87

 

Line 87. The first sentence is redundant, so please delete it or place it in a more suitable position in the paragraph.

Response: Thank you for your advice. We have removed this sentence as you suggested.

 

Line 106. Please revise the end of the sentence to “… factors with climate factors for secondary natural oak forests”.

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

However, to the best of our knowledge, there has yet to be a study that has modeled the site index model and considered the interaction of site factors with climate factors for secondary natural oak forests. L127

 

Line 95-106. This paragraph can be organised and improved by smoothing the transition of points between sentences, enhancing connectivity, and elucidating the study's central idea.

Response: Thank you for your suggestion. We have made the changes in the revised draft as you suggested:

Oak forests, constituting 14% of China's natural forest area, play a vital role in water conservation, soil retention, and ecological stability, underscoring their research significance. Hunan, a region predominantly characterized by hilly and mountainous terrain, is home to a significant expanse of subtropical oak natural secondary forests [50]. However, the majority of these forests are currently classified as low-quality and underperforming, highlighting an urgent need for elevated management standards [51]. Consequently, there is a pressing demand for comprehensive research into advanced management theories and technologies to enhance the productivity and quality of these vital ecosystems. A key challenge in forestry research, particularly for natural secondary forests, is the accurate assessment of site quality and prediction of growth. This is essential for effective management of tree species across regional scales.

 

Line 108. For the second objective, isn’t “to evaluate” a better word to describe the work than “to measure”?

Response: Thank you for your corrections. The second research purpose we deleted. Because our main research purpose is to develop a model for predicting site index in subtropical oak natural secondary forests, taking into account the interaction between site factors and climate factors. The previous purposes serve the third purpose.

4.Materials and Methods.

 

Line 233. The model was fitted using the entire dataset. Is that better than fitting the model on half or 75% of the data and validating it using the remaining data? Is there any evidence that the former is better than the latter?

Response: Thank you for your corrections. Our model are using the entire dataset. Also, we have performed leave-one-out cross-validation method to evaluate and validate the accuracy and error of the model.

In this paper, the model fitting was conducted using the entire dataset. Statistical disparities among models were examined by likelihood ratio tests. In the absence of independent datasets, we employed leave-one-plot-out cross-validation (LOOCV) to evaluate the predictive capability of the mixed-effects models and the reliability of the parameter estimations. [82–84]. L256-260

 

Wang, J.; Jiang, L.; Yan, Y. The Impacts of Climate, Competition, and Their Interactions on Crown Width for Three Major Species in Chinese Boreal Forests. Forest Ecology and Management 2022, 526, 120597. 

 

Is there a subtopic explaining the process/analysis of finding the answer for the second aim of the study?

Response: Thank you for your corrections.

We compared the effects of ST, CT and ST*CT on dominant tree height growth by comparing the AIC and BIC values of a mixed effects model containing random effects of ST, CT and ST*CT. We also used RF to rank them using dominant tree height as the dependent variable and age, ST, CT and ST*CT as the independent variables.

 

5.Results.

 

Line 250. Please name the subtopic to reflect the study's first aim, for example, “3.1 Factors affecting growth and growth responses”.

Response: Thank you for your corrections.

3.1. Factors Affecting Growth and Growth Responses L273

 

Please create a new subtopic to indicate the findings for the second aim, such as “3.2 Impacts of site and climatic factors on dominant height.”

(Since the rest of the results, starting from Section 3.2, are associated with the third aim).

Response: Thank you for your corrections. The second research purpose we deleted. Because our main research purpose is to develop a model for predicting site index in subtropical oak natural secondary forests, taking into account the interaction between site factors and climate factors. The previous purposes serve the third purpose.

 

 

Were oak species included in the data analysis? What was the finding?

Response: In the previous data processing, we considered the effects of species composition and admixture on the construction of site index models, but we found that the species composition in our study area had very little improvement in the accuracy of the construction of site index models.

 

6.Discussion.

 

Please clearly indicate the discussion for each aim of the study. Separate them into three subtopics.

Response: Thank you for your corrections. The second research purpose we deleted. Because our main research purpose is to develop a model for predicting site index in subtropical oak natural secondary forests, taking into account the interaction between site factors and climate factors. The previous purposes serve the third purpose.

 

Can Figure 7 (and the associated explanation or description) be placed under Results? Also, for Figure 7, the legend is probably optional (can be deleted), or the acronyms are spelt out.

Response: Thank you for your corrections. We have included this section as a complementary finding to purpose (1) and therefore placed it in the discussion section. We have modified Figure 7 as you suggested below.

 

before	now

 

 

Was oak species a critical factor affecting the site index of the studied forest?

Response: Thank you for your corrections. No, it wasn’t. During data preprocessing we found that oak species were not a key factor influencing site index.

 

Lines 522-525. If this is one of the study's conclusions, please state it under Conclusions.

Response: Thank you for your corrections. That's not the main conclusion.

 

7.Conclusions.

 

Please organise the conclusion to reflect the study's three aims clearly.

Response: Thank you for your corrections. Our main purpose is to develop a model for predicting site index in subtropical oak natural secondary forests, taking into account the interaction between site factors and climate factors.

 

Lines 542-545. The sentence can probably be revised: “The study showed that our site index modelling method (approach) could offer valuable insights for subtropical secondary natural oak forest management under complex site and climatic conditions. Additionally, it can potentially be used to predict (assess) precisely the regional secondary natural oak forest site index and productivity in the face of future climate change.”

Response: Thank you for your corrections. We have made the changes in the revised draft as you suggested:

The study showed that our site index modelling method (approach) could offer valuable insights for subtropical secondary natural oak forest management under complex site and climatic conditions. Additionally, it can potentially be used to predict (assess) precisely the regional secondary natural oak forest site index and productivity in the face of future climate change. L565-569

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

This paper evaluates the effects of site and climate factors on tree height growth in a secondary oak forest. They used random forest method, correlation analysis, and analysis of variance to determine the main site and climate factors. They found elevation, slope, position have important effects. they developed several combinations of site-climate types through hierarchical clustering and found mixed-effect model with random effects of multiple groups improve model performance. Overall, I think the paper  is well written but needs to address the following comments:

- title: not sure why this phrase was used here: "polymorphic site index". "polymorphic" generally referred as existence of a gene in several allelic forms. I do not think it is the correct word here

- abstract: not sure what M3, M3.12 means in this abstract. 

- introduction: L49-52 note that topography is also used to model other ecological aspects of trees such as fecundity (Qiu et al., 2021, Boehm et al., 2021) and mortality (Guarin and Alan, 2005) which are two other important fitness of forest trees. 

Qiu, Tong, et al. "Is there tree senescence? The fecundity evidence." Proceedings of the National Academy of Sciences 118.34 (2021): e2106130118.

 

Boehm, Alex R., et al. "Slope and aspect effects on seedbed microclimate and germination timing of fall-planted seeds." Rangeland Ecology & Management 75 (2021): 58-67.

Guarín, A, and Alan H. T. "Drought triggered tree mortality in mixed conifer forests in Yosemite National Park, California, USA." Forest ecology and management 218.1-3 (2005): 229-244.

- L129: what is the temporary plot here? 

- L 163: is tree age from tree ring record?

- L205-207: not sure if those equations (or greek letters) were properly used. You might want to check the NLME package and their manuals.  

- Figure 2b: it is symmetric so there is no need to include both dots and numbers. 

- figure 4: not sure if phylogeny figure is the correct way for hierarchical clustering. There is no evolutionary history and might confuse the readers. 

Author Response

Comments and Suggestions for Authors

This paper evaluates the effects of site and climate factors on tree height growth in a secondary oak forest. They used random forest method, correlation analysis, and analysis of variance to determine the main site and climate factors. They found elevation, slope, position have important effects. they developed several combinations of site-climate types through hierarchical clustering and found mixed-effect model with random effects of multiple groups improve model performance. Overall, I think the paper is well written but needs to address the following comments:

 

Response: Thank you for your careful review of our manuscript. Based on your suggestions, we have further enhanced the manuscript for revision.

 

1. title:

not sure why this phrase was used here: "polymorphic site index". "polymorphic" generally referred as existence of a gene in several allelic forms. I do not think it is the correct word here.

Response: "Polymorphic Site Index" is a forestry term. The term has been widely used in many forestry studies. Here are some articles that use the term:

(1). Newton, P.F. Base-Age Invariant Polymorphic Site Index Curves for Black Spruce and Balsam Fir within Central Newfoundland. North. J. Appl. For. 1992, 9, 18–22, doi:10.1093/njaf/9.1.18.

(2). Elfving, B.; Kiviste, A. Construction of Site Index Equations for Pinus Sylvestris L. Using Permanent Plot Data in Sweden. For. Ecol. Manage. 1997, 98, 125–134, doi:10.1016/S0378-1127(97)00077-7.

(3). Griswold, H. Polymorphic Site Index Curves for Two Hardwood Species in West Tennessee : Sweetgum (Liquidambar Styraciflua L.) and Southern Red Oak (Ouercus Falcata Michx). Masters Theses 1976.

(4). Palahı́, M.; Tomé, M.; Pukkala, T.; Trasobares, A.; Montero, G. Site Index Model for Pinus Sylvestris in North-East Spain. For. Ecol. Manage. 2004, 187, 35–47, doi:10.1016/S0378-1127(03)00312-8.

 

2. abstract:

not sure what M3, M3.12 means in this abstract.

Response: M3 denotes the optimal base model Mitscherlich formula (Table 4).

 “Site-climate interaction type as a random factor enhanced model (M3.12) performance and prediction accuracy (R² from 0.1940 to 0.8220) compared to the optimum base model.” Model M3.12 in the abstract should be changed to model M3.4, which represents a mixed-effects model with ST*CT as a random effect (Table 7). We have made the corresponding change in the abstract of the revised version(L24).

 

3.introduction:

L49-52 note that topography is also used to model other ecological aspects of trees such as fecundity (Qiu et al., 2021, Boehm et al., 2021) and mortality (Guarin and Alan, 2005) which are two other important fitness of forest trees.

 

Qiu, Tong, et al. "Is there tree senescence? The fecundity evidence." Proceedings of the National Academy of Sciences 118.34 (2021): e2106130118.

 

Boehm, Alex R., et al. "Slope and aspect effects on seedbed microclimate and germination timing of fall-planted seeds." Rangeland Ecology & Management 75 (2021): 58-67.

 

Guarín, A, and Alan H. T. "Drought triggered tree mortality in mixed conifer forests in Yosemite National Park, California, USA." Forest ecology and management 218.1-3 (2005): 229-244.

Response: The following changes have been made to L52-53 in the revised draft in response to your suggestions: “Topography is also used to model other ecological aspects of trees such as fecundity [17,18] and mortality [19].”

 

L129: what is the temporary plot here?

Response: The term "temporary plot" refers to a "temporary sample plot". It's a forestry term. It is defined as a sample plot in which one-time observations are made. We have made the following change in L131 of the revised version: replace "comprising 51 permanent and 50 temporary plots" with "comprising 51 permanent and 50 temporary sample plots".

 

L 163: is tree age from tree ring record?

Response: Yes. We accounted for the acquisition of tree ages in our article L135-137. The original text reads: "We selected about four dominant oaks to calculate the average height of the dominant trees, used growth cones to drill the cores, and determined the age of the trees by cross-dating."

L205-207: not sure if those equations (or greek letters) were properly used. You might want to check the NLME package and their manuals.

Response: We have made the corresponding changes in L206-212 of the revised draft in accordance with your suggestions. We used the nlme package to fit the model, but the form of the expressions refer to the literature [43].

Zhang, X.; Fu, L.; Sharma, R.P.; He, X.; Zhang, H.; Feng, L.; Zhou, Z. A Nonlinear Mixed-Effects Height-Diameter Model with Interaction Effects of Stand Density and Site Index for Larix Olgensis in Northeast China. Forests 2021, 12, 1460.

Figure 2b: it is symmetric so there is no need to include both dots and numbers.

Response: We have made the following changes to Figure 2b as you suggested. At the same time we have made the corresponding changes in the revised draft.L267-269

before	now

 

Figure 4: not sure if phylogeny figure is the correct way for hierarchical clustering. There is no evolutionary history and might confuse the readers.

Response: The hierarchical clustering approach we use has been successfully applied to mixed effects models. As in reference [14].

Duan, G.; Lei, X.; Zhang, X.; Liu, X. Site Index Modeling of Larch Using a Mixed-Effects Model across Regional Site Types in Northern China. Forests 2022, 13, 815.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I have no additional comments.

Author Response

Comments and Suggestions for Authors: I have no additional comments.

Response: Thank you for taking the time to review our manuscript. We appreciate your thorough evaluation and are pleased to hear that you have no additional comments. Your feedback has been invaluable in improving the quality of our work, and we are grateful for your contributions.

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript is well written. There are only a few minor things to be revised, as follows.

 

Line 20. Please correct the double comma.

Line 99. Correct the double-space tab, also, in Lines 100 and 107.

Line 165. Please add a space tab before the word “Random...”.

Line 171. Please delete the extra full stop before [61,62].

Line 233. Correct the probably double-space tab before “Utilising…”.

Line 243. Delete the extra full stop before the references.

Line 186 – 254. Please name the software(s) used to analyse the data (Base model, NLME, etc.).

Line 429. Delete the extra full stop before the references.

Line 432. Please italicise the species name.

Line 454-455. The authors mentioned/acknowledged that tree species affect tree height or diameter based on the data from other studies. So, please note that in their research (in the present paper), however, tree species have little effect on tree height or diameter for oak forests. (They have mentioned that in their response to the reviewer’s comments). Also, please discuss why so in their research.

Author Response

Comments and Suggestions for Authors:

The manuscript is well written. There are only a few minor things to be revised, as follows.

Response: Thank you for your thorough review and valuable feedback. We are grateful for your positive comments about the manuscript and your detailed suggestions for improvement. Below is our point-by-point response to the minor revisions:

 

Line 20. Please correct the double comma.

Response: The double comma has been corrected.

 

Line 99. Correct the double-space tab, also, in Lines 100 and 107.

Response: The double-space tab has been corrected.

 

Line 165. Please add a space tab before the word “Random...”.

Response: A space has been added before the word "Random...".

 

Line 171. Please delete the extra full stop before [61,62].

Response: The extra full stop before [61,62] has been deleted.

 

Line 233. Correct the probably double-space tab before “Utilising…”.

Response: The double-space tab before "Utilising…" has been corrected.

 

Line 243. Delete the extra full stop before the references.

Response: The extra full stop before the references has been deleted.

 

Line 186 – 254. Please name the software(s) used to analyse the data (Base model, NLME, etc.).

Response: We have added the names of the software used to analyze the data, including Base model and NLME.

 

Line 429. Delete the extra full stop before the references.

Response: The extra full stop before the references has been deleted.

 

Line 432. Please italicise the species name.

Response: The species name has been italicized.

 

Line 454-455. The authors mentioned/acknowledged that tree species affect tree height or diameter based on the data from other studies. So, please note that in their research (in the present paper), however, tree species have little effect on tree height or diameter for oak forests. (They have mentioned that in their response to the reviewer’s comments). Also, please discuss why so in their research.

Response: We have revised the manuscript to clarify that, while previous studies indicate that tree species can affect tree height or diameter, in our research on oak forests, tree species have little effect on these variables. We also added a brief discussion explaining why this is the case, noting the similar growth characteristics of oak species in the study area and the dominant influence of climatic factors, which may overshadow species-level differences.

We believe these revisions have addressed your concerns, and we sincerely appreciate your helpful suggestions.

Reviewer 3 Report

Comments and Suggestions for Authors

thanks for addressing my comments

Author Response

Comments and Suggestions for Authors: thanks for addressing my comments.

Response: Thank you for your positive feedback. We are glad to know that our revisions have adequately addressed your comments. Your suggestions were very helpful in improving the manuscript, and we greatly appreciate your time and effort.