Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study addresses an important topic and provides valuable insights into the interactions between vegetation transpiration and soil moisture. However, improvements are needed in the clarity of objectives, figure presentation, and referencing. I recommend major revisions before the manuscript can be considered for publication.

- The abstract is too long and descriptive. It should be more concise, focusing on the key findings, methodological novelty, and implications.

- While the introduction cites many studies, the gap is not clearly articulated. The authors should explicitly highlight what is missing in existing research and how this study advances knowledge. Authors can take advantage of some papers like Meteorological and vegetation effects on the thermal analysis of slopes, A specialized boundary condition for soil–vegetation–atmosphere interaction in embankments.

- The use of GLDAS-Catchment data is appropriate, but the authors should explain why this dataset is more suitable than other available sources (e.g., ERA5, CMIP).

- Several figures (e.g., Figures 2 and 3) are difficult to read due to small fonts. They need better resolution and improved labeling.

- Terms like “resonance cycle,” “consumption-driven mechanism,” and “false wetting” are used without clear definition or sufficient explanation. The language should be simplified for a broader readership.

- Some references are outdated or lack proper formatting. For example, “Error! Reference source not found.” appears in multiple places, indicating citation errors that must be corrected.

- The conclusions summarize results but do not clearly state the broader implications for eco-hydrological management or climate adaptation. Policy relevance and practical applications should be added.

- Some units (e.g., mm/yr for transpiration, soil moisture changes) are not consistently presented across text, figures, and tables, which may confuse readers.

- The authors do not discuss limitations such as data uncertainty, spatial resolution constraints, or model biases. A clear limitations section is necessary.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Xie et al. present an interesting analyses of soil and vegetation water coupling in a hydrological model using the Fujian Province as a case study.  The study found strong coupling in the region and reported spatial and temporal changes associated with this coupling.  I found the spatiotemporal analyses of the dataset to be interesting and somewhat novel in their application. However, there are major issues that limit the impact and citability of the manuscript.  First, there is no clear justification or rationale for the reason that the Fujian Province was chosen as a case study.  Is this a region that is known for its strong soil and vegetation water coupling, or a region of rapid change?  Second, the methods section provides little detail to assess the robustness of the analyses conducted.  How were uncertainties in the data assessed and considered in the analyses?  How was soil and vegetation water coupling represented in the model used to calculate transpiration?  Is transpiration represented well in the model and how does it compare with actual measures of transpiration?  What is the uncertainty involved with using model derived transpiration?  Third, the rationale for the seasonal separation of the dataset presented in the cross wavelet transforms and singular value decomposition analyses is unclear.  These statistical tools are meant to analyze continuous timeseries, and separating the timeseries into seasons may hide correlation and phase relationships that occur in between seasonal transitions.  Lastly, the introduction and discussion had some errors, missed important papers in the field, and lacked a sufficient coherent narrative that justified the rationale for the study and provided sufficient and satisfying explanation of all the results.  In particular, the Discussion was mostly a rehash of the results, and relied little on the existing scientific literature for context and explanation.  I believe that the study is important, but requires revision to realize its full potential.  Below I list some minor edits to consider.

1) there appear to be some citation errors in lines 345-363.

2) If the papers goal is to investigate soil vegetation water coupling, then why are temporal trends for the region presented in Figure 2?  How do these figures compliment the other figures?

3) References are missing key papers in the field and other studies that have conducted similar work or used similar statistical techniques (see recommendations below).  It is also curious that many of the journals cited are low impact regional journals that are not accessible to a wide audience. For example, I am at a R1 university in the US and do not have access to the "Chinese Journal of Ecology", "Annals of Forest Science", or any of the "Acta" journals. None of the AGU journals (Earth's Future, Geophysical Research Letters, Water Resources Research, Earth Surface) have been cited, which is curious since these high impact journals are known for the type of research presented in the paper.     

List of similar/relevant articles:

Wu et al. (2025) Strengthening coupling between vegetation and soil atmosphere compound drought over the past two decades. Earth's Future.

Angelini et al. 2010 On the coupling between vegetation and the atmosphere. Theor. Appl. Climatol.

Dubbert (2018) Water fluxes mediated by vegetation: emerging isotopic insights at the soil and atmosphere interfaces. New Phytologist.

Rocha et al. (2025) Atmosphere, vegetation, and soil water coupling determined by stomatal regulation of transpiration. Ecosystems. 

Grinsted A, Moore J, Jevrejeva S. 2004. Application of cross wavelet transform and wavelet coherence to geophysical time series. Nonlinear Process Geophys 11:561–566.

Gao W, Li BL. 1993. Wavelet analysis of coherent structures at the atmosphere-forest interface. J Appl Meteorol Climatol 32:1717–1725.

Liu Q, Hao Y, Stebler E, Tanaka N, Zou CB. 2017. Impact of plant functional types on coherence between precipitation and soil moisture: a wavelet analysis. Geophys Res Lett 44(12):197.

Lian X, Piao S, Chen A, Wang K, Li X, Buermann W, Huntingford C, Peñuelas J, Xu H, Myneni RB. 2021. Seasonal biological carryover dominates northern vegetation growth. Nat Commun 12:983.

Koster RD, Guo Z, Yang R, Dirmeyer PA, Mitchell K, Puma MJ. 2009. On the nature of soil moisture in land surface models. J Clim 22:4322–4335.

Seneviratne SI, Corti T, Davin EL, Hirschi M, Jaeger EB, Lehner I, Orlowsky B, Teuling AJ. 2010. Investigating soil moisture–climate interactions in a changing climate: a review. Earth-Sci Rev 99:125–161.

Stoy PC, Dietze MC, Richardson AD, Vargas R, Barr AG, Anderson RS, Arain MA, Baker IT, Black TA, Chen JM, Cook RB, Gough CM, Grant RF, Hollinger DY, Izaurralde RC, Kucharik CJ, Lafleur P, Law BE, Liu S, Lokupitiya E, Luo Y, Munger JW, Peng C, Poulter B, Price DT, Ricciuto DM, Riley WJ, Sahoo AK, Schaefer K, Schwalm CR, Tian H, Verbeeck H, Weng E. 2013. Evaluating the agreement between measurements and models of net ecosystem exchange at different times and timescales using wavelet coherence: an example using data from the North American carbon program site-level interim synthesis. Biogeosciences 10:6893–6909.

Vargas R, Detto M, Baldocchi DD, Allen MF. 2010. Multiscale analysis of temporal variability of soil CO₂ production as influenced by weather and vegetation. Global Change Biol 16:1589–1605.

 

 

 

 

  

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Dear authors!
As a geographer, I would recommend the following additions to improve the article and increase the interest of biologists and geographers:
In section 2.1. The following positions could be added: a) The climate should be presented according to the Köppen climate classification. b) It is obvious that transpiration and soil moisture are associated with a certain type of vegetation and type of soil. It would be good to make a landscape description of the province. Moreover, obvious regional differences arise in the results later on, which could be interpreted from a landscape standpoint. 

In section 2.2  To verify soil moisture data, it is advisable to also use instrumental data (in-situ), and not just calculated data.

 

Comments on the Quality of English Language

Unfortunately, I am not a native English speaker and cannot adequately assess this criterion.

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript by Xie et al. considers relation between transpiration of vegetation and soil moisture. This investigation seems to be interesting. However, I have some comments.

• The GLDAS Catchment Land Surface Model (CLSM) should be described in more details. Please, add some principal equations.
• What is function which used in Cross Wavelet Transform?
• Please, add temperature trends of spring, summer, autumn, and winter.
• Please, discuss in more details the relation between transpiration and soil moisture. Was the part of the soil water inaccessible to plants? Please, discuss the physiology of plants under excess water in the soil.
• The actuality of investigation should be stressed.
• Figure 7. “(c) Normalized temporal coefficients for the root-zone soil moisture field (Left field) and the vegetation transpiration field (Right field).” Left and right should be replaced by blue and red.
• Section 3.3.2. “Error! Reference source not found” should be improved.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have thoroughly addressed all the comments and suggestions provided in the previous review. The responses are clear, well-supported, and demonstrate a strong understanding of the subject matter. The manuscript has improved in both clarity and technical quality as a result.  

Author Response

Thank you sincerely for your affirmation.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have done an adequate job at addressing previous comments.  I think that this is an interesting study that is worth publishing. 

Author Response

Thank you sincerely for your affirmation.

Reviewer 3 Report

Comments and Suggestions for Authors

Dear authors, in the new version of the publication you have added information about vegetation and soils of province 123-131. But this information still has a rather superficial description. without specifying the species composition. Then there is the mention of one of the species 525-527. But again, the distribution of tree species in various parts of the province is unclear. This raises questions about the Practical Implications section. There you specifically write that you should pay attention to the species composition 559-565. And what kind of species is it? I'm bringing it once again for my "bad" English.

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

I have not other comments. The manuscript can be accepted.

Author Response

Thank you sincerely for your affirmation.