Water Use Characteristics of Populus euphratica Oliv. and Tamarix chinensis Lour. at Different Growth Stages in a Desert Oasis

Round 1

Reviewer 1 Report

The article can contribute significantly to the growing demand for literature on the water use efficiency of the forest ecosystem. The manuscript is well-written. I have only a few comments:

Table 1. Please descript more the table. Data used were taken in 2020?

Line 211 : ‘P. euphratica ‘ must be in italics

Figure 4: In the figure caption, scientific names must be written in italics format

Lines 277-280: ‘Young 277 trees are connected to the root system of mature trees at some period, and water is primarily acquired from mature trees. Therefore, there is no significant difference in the source of water among the growth stages of P. euphratica.’ How can you say this? Did you examine or try excavating trees' root systems below the soil? Maybe cite some literatures that have proven this?

Lines 282-283: ‘Since there was water in the river in 2019, river water, deep soil water and groundwater were the main water sources of P. euphratica.’ Why it gone dry? Has the ecosystem experienced severe drought during the period? Try to explore the concept of hydraulic lift and hydraulic redistribution when soil water is limiting. These studies may help you gain some insights along this line.

https://nph.onlinelibrary.wiley.com/doi/10.1111/j.1469-8137.2010.03245.x

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2010JD014568

https://www.sciencedirect.com/science/article/pii/S0168192321000642

 

Line 324: How WUE was estimated? At least describe them in the methods section

Conclusion: The conclusion for me comes off as repetitive of the abstract or a summary of the results section. I would love to read striking points and take-home message that will linger in the readers’ minds. What is the novelty, how does the study elucidate some questions along this field, and the contributions the paper may offer to the scientific community.

Author Response

Dear Sir/Madam,

    Thank you so much for your kind encouragement on our manuscript entitled “Water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages in a desert oasis” (Forests-1535697) and sending us the review on our manuscript.

    We greatly appreciate reviewer for your valuable comments and constructive suggestions. We have carefully addressed these points in our revised manuscript and a point-to-point response to the comments has been detailed in our Cover Letter, in which the comments are written in italics followed by our responses in regular text. In addition, the changes or revision were marked with red text in new version of the manuscript.

    Now, we are resubmitting the latest vision of our manuscript to you.

Best wishes,

Yanbo Wan

Author Response File: Author Response.pdf

Reviewer 2 Report

General comments

I have read the manuscript (forest -1535697). Entitle: Water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages in a desert oasis written by Yanbo Wan et. al., for publication of forest MDPI. In this study, the Author investigated the water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages by analyzing the potential plant sources and δ18O 15 values of plant xylem of different species. In this study, author found that the water use efficiency (WUE) of P. euphratica and T. chinensis increased in parallel with the tree sizes. Overall, the results in this experiment indicate that the effectiveness of vegetation restoration strategies can be improved by considering the differences in water use characteristics of vegetation types in this sense the manuscript is much valuable. The overall research is well conducted, and research is obvious application potential. However, I found some points especially the flow of the text is not smooth and sometimes I found the shallow writing and lack of potential references, and lack of connection of story in different paragraphs especially in the introduction and discussion sections. In discussion, the author should be deal with the plant-water relation and hydraulic perspectives and the author should deal with plant biology. I also found the lack of potential and appropriate references to support the findings. The author should provide enough examples and their interpretation of different traits of physiological and water-relations about the plant water use by the plant. I mention some tips and recommend some literature this will help to improve this manuscript quality better than before. Overall after I evaluate this manuscript, I request the author for the “REVISION” and also, I request to authors for revision according to the rules of the journal and correct the bibliography.

 Major suggestions

1) Abstract Issue: The author wrote the important finding in their abstract, but the text seems more confusing. The author should focus on the novelty of the finding in the abstract rather than just comparison. Some text in the abstract seems meaningless and that made the confusion to understanding by the normal reader because it is not matching well with the finding. For example, see the Line no. 21-23, what is this mean? The author should connect these things with plants not only solely only water sources. Please modify and rephrase the most text in the abstract it is not well connected with the title. Where the author deals with the stage of the growth and their water use / actually I unable to figure out. Please abstract should write the abstract more logical, short, concise, and informative. Your abstract should reflect your study and major findings while shortly observed by readers. Please make the necessary corrections.

 

2) Introduction: Improve your introduction more logically. I saw the author did a good starting introduction by including the text related to the ecosystem and preventing desertification by analyzing the water-use techniques in mixed forests. In the field measurements of plant water-use analyzing (WUE analysis), there is a different method such as gas exchange, carbon isotopic discrimination, eddy covariance techniques, and remote sensing. The most important thing is this study author investigated the water use characteristics of P. euphratica and T. chinensis at different growth stages in the same habitat using stable isotope δ13C in two consecutive years in 2019 and 2020. Therefore, the author should be more focused to include enough related literature especially related to those which are using the δ13C to determine the plant water use. Among them, the article Entitle “Response of drought stress in prunus sargentii and larix kaempferii ...https://doi.org/10.1016/j.foreco.2020.118099”. Please refer and cite this article somewhere in the second paragraph to describe the carbon isotope and determine the plant water use and mention the text “Carbon Isotopic composition is the useful method to determine the drought resistance to provide the insights of the chemical, physical and metabolic process involved in carbon transformation in the stressed plant that determines the water utility and water conservation status for the forest species”.

3) Hypothesis of the study: The author well describes the objective of the study. However, the objective of the study is repeated twice in the consequently two lines. Please see Line 80-81 and also see objective 1. Is not it repeated? It reduces the strength of your manuscript, please. The author should revise the last two paragraphs and make one and include the sequential flow of the hypothesis as well as the objective of the study together. The author should mention the clear hypothesis of the study and should emphasize that what is done in the previous study and what is the novelty included in the present study. The author should present very clearly. The hypothesis of the study is important. Please write and rephrase your hypothesis as well because it needs to introduction section to strengthen the paper. The hypothesis should be very clear in the introduction sections because, without appropriate literature, questions, or hypotheses in the introduction section the entire text will be unclear.

Other comments and suggestions

 4) Line 97: The author should to a little bit strengthen the information of Figure description in “Figure 1” in the scientific writing should be described figure shortly. Please revise this. To reduce the text duplication author may reduce some information in the 2.1 paragraph text. Also, both of the figures are low visibility, and the text is somewhat small please also revise the figures as well.

5) Line 98:  Please revise the subtitle of 2.2, it is not clear what is this means (title should be itself clear).

6) Line 260:  Please revise the figure footnote and shortly indicate the Young tree, mature and Overmature tree (range in the year). I have a question that why Tamarix chinensis have did not measure the Delta ¹⁸C in the year 2019.

7) Line 263-264 (discussion 4.1):  In the discussion, the author should deal with the plant water relation in section 4.1. For that author should deal with the physiological traits (Pn, gs) as well because control the water use efficiency. Stomatal conductance (gs) plant a very important role in having the mechanism of closing and opening based on the evapotranspiration. I do not see this related clear-cut information in the discussion section. For further improvement of the discussion, I request to author to connect this part by dealing with the stomatal controlling gs traits and carbon isotope by citing these two articles which are good and the latest references for the discussion section. https://doi.org/10.1016/j.scitotenv.2021.146466 Title: Evaluation of morphological, physiological, and biochemical… and (2) doi: 10.3390/plants8070232. Please mention the text like “WUE is species-specific, and it’s controlled by the stomata opening and closing because stromal full opening and partial opening of stomata partial closing cause the turgid the plant part”. Moreover, it may be varying the transpiration rate from the leaf canopy level, this information author should be mentioned in the discussion.

8) Conclusion section (Line no. 359)

Author can still improve the conclusion section by revising the concise text and improving the flow of writing please. The conclusion section should be in a good flow with include all necessary components of the study and do not repeat the result section in the conclusion. Conclusions should be present the future insight of the research based on your current finding and the strength of your results for the future research guideline.

 

9) Line no. 382

10) Reference: please double-check the citations, their style, and spell check, and other grammatical errors. moreover, I request to authors for revision throughout the manuscript according to the journal rules.

Good Luck!

Author Response

Dear Sir/Madam,

    Thank you so much for your kind encouragement on our manuscript entitled “Water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages in a desert oasis” (Forests-1535697) and sending us the review on our manuscript.

    We greatly appreciate reviewer for your valuable comments and constructive suggestions. We have carefully addressed these points in our revised manuscript and a point-to-point response to the comments has been detailed in our Cover Letter, in which the comments are written in italics followed by our responses in regular text. In addition, the changes or revision were marked with red text in new version of the manuscript.

    Now, we are resubmitting the latest vision of our manuscript to you.

Best wishes,

Yanbo Wan

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Dear Author

I have read the revised manuscript (Forest-1535697). Entitle: Water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages in a desert oasis for publication of Forest MDPI. This is the second submission made by the author. The author addressed all the questions and suggestions that I raised the issue in the review of the original manuscript. I satisfy the author’s revisions throughout the paper. Especially author improved the introduction and discussion section very well inflow. The abstract issue is also solved by the author. Now, this manuscript improved the flow of writing, which was comparatively shallow in the original version but in this revised copy author addressed all the quarries and suggestions very well. Before accepting this manuscript if there is anything needed to be revised by the author especially English grammar or spell check, I request this manuscript is currently in “Minor Revision” and any grammatical error author may improve in this stage. Thank you.

 

Author Response

Dear Sir/Madam,

    Thank you so much for your kind encouragement on our manuscript entitled “Water use characteristics of Populus euphratica and Tamarix chinensis at different growth stages in a desert oasis” (Forests-1535697) and sending us the review on our manuscript.

    We greatly appreciate reviewer for your valuable comments and constructive suggestions. We have carefully addressed these points in our revised manuscript and a point-to-point response to the comments has been detailed in our Cover Letter, in which the comments are written in italics followed by our responses in regular text. In addition, the changes or revision were marked with red text in new version of the manuscript.

    Now, we are resubmitting the latest vision of our manuscript to you.

Best wishes,

Yanbo Wan

 

Author Response File: Author Response.pdf