Analysis of the Spatiotemporal Changes in Cropland Occupation and Supplementation Area in the Pearl River Delta and Their Impacts on Carbon Storage
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This study quantitatively assesses the spatiotemporal changes in cropland occupation and supplementation in the Pearl River Delta from 2000 to 2020 using the InVEST model, analyzing the spatial clustering of carbon storage changes caused by variations in cropland area. The PLUS model was employed to simulate land-use patterns and the spatial distribution of carbon storage under four future development scenarios. This study contains some interesting findings which provide references for regional carbon sequestration enhancement and support sustainable socio-economic development.
However, the article still lacks some key content in the introduction and conclusion sections. Therefore, MAJOR revision is required before this manuscript can be accepted for publication.
1. The first sentence of the abstract should introduce the background or significance of the research.
2. The Discussion should be Section 5, and Conclusions should be Section 6.
3. Line 562 should be Figure 11.
4. Equation 7 needs to be corrected.
5. The discussion section should include results from other studies for validation of the results.
6. The conclusion section, in addition to important findings, should also include the paper’s innovative methods and suggestions for future research. Moreover, emphasizing the universal value of the study for readers from other countries and continents is also very necessary.
7. The manuscript has a Percent match of 33%, which necessitates a reduction in repetition to enhance the clarity and conciseness of the text.
Author Response
Dear Reviewer,
We would like to express our sincere gratitude for your thorough and insightful review of our manuscript, "Coupling InVEST-PLUS Model to Analyze the Spatiotemporal Changes in Cropland Occupation and Supplementation Area in the Pearl River Delta and Its Impact on Carbon Storage."Your valuable comments and suggestions have been instrumental in improving the quality of our work. We appreciate the time and effort you dedicated to reviewing our manuscript and providing such constructive feedback.
We have carefully considered all your comments and have made the necessary revisions to address your concerns. Your insights have greatly enhanced the clarity and depth of our study, and we are confident that the manuscript has been significantly strengthened as a result.
The point-by-point revisions are detailed as follows:
Suggestion 1: The first sentence of the abstract should introduce the background or significance of the study.
Response1： Thank you for your suggestion. I have reintroduced the research background, which is highlighted in the revised abstract. 11-13
Suggestion 2、3、4: The discussion should be Section 5, the conclusion should be Section 6, and line 562 should refer to Figure 11. Formula 7 needs to be corrected.
Response2：Sincerely thank you for pointing out these detailed issues. I have made the necessary corrections, and the revised sections are highlighted in the manuscript. 531、528、245
Suggestion 5: The discussion section should include results from other studies to validate the findings.
Response5：Thank you for your suggestion. Your advice is very professional, and indeed, validation through other studies is necessary. I have included results from other studies in the discussion. The revised discussion can be found on page 18, Section 5.1, lines 6-9 of the manuscript.537-543
Suggestion 6: In addition to important findings, the conclusion section should also include the innovative methods of the paper and suggestions for future research. Additionally, it is essential to emphasize the general value of the research to readers from other countries and continents.
Response6：Thank you for your valuable suggestion. The innovative methods and suggestions for future research are discussed in the discussion section. The general value of the research to readers from other countries and continents has been added to the discussion section and is highlighted at the end of the first paragraph on page 20. 615-616
Comment 7: The manuscript has a 33% similarity rate; the repetition needs to be reduced to improve the clarity and conciseness of the text.
Response7：Thank you for pointing this out. I have made targeted revisions to sections with higher similarity, such as the introduction, data sources, and formulas.
Thank you once again for your important contribution to our research. We look forward to your feedback on the revised manuscript.
Warm regards,
ShuQi Huang；
Dafang Wu
Guangzhou Univeity
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments and Suggestions for AuthorsIn general the paper is well written, logically structured and well presented. There are a few typos. The purpose of the research is clear and the approach would seem to have merit in relation to current concerns about CC and carbon capture/storage. The paper is quite long but detailed and the discussion and conclusions seem to be fine. My main criticism would be the clarity in some places e.g. the illustrations and some of the statements e.g. in the Abstract where there is reference to INVEST, then PLUS and in the title the INVEST-PLUS model. This is a li tttle confusing and simply needs to ensure that reference is made accordingly throughout. I also wonder if there should be some clarification about land-use and land-cover - I am assuming that land-use is the focus. The illustrations are fine - except throughout I am unclear about some of the legends used. For example, Figure 1 - what is the colour scheme and what are the references to high and low - this conflicts also with the caption which refers to a study area map. There are two Table 1, and I assume that the second one should be Table 2. But at the end, there is a piece of text: ock Hotspot Analysis. What is this? It does not seem to relate to the text or the table. In Figure 2, I think the colouring for the cropland needs to change and the illustration made clearer. The Green and Red are fine cartographically. Throughout the illustrations should resort to a more basic North Arrow rather than the default one provided by ESRI that looks as if it has come from a Pirate's Treasure Map. After this, please look at each of the illustrations carefully and think about how best to visually portray the information you are trying to communicate via the maps e.g. the cartography, the colour use etc. This is important for the reader to be able to get a visual idea of the outcome of your analysis. All maps also need some locational information (annotation on them) and should be larger format. Whilst the analysis is useful, what about the wider context in terms of the implications of your findings and how these relate to agricultural planning etc. It might be interesting to consider how the research can potentially improve things?
Author Response
Dear Reviewer,
Thank you for your detailed review and valuable feedback on our manuscript, "Coupling InVEST-PLUS Model to Analyze the Spatiotemporal Changes in Cropland Occupation and Supplementation Area in the Pearl River Delta and Its Impact on Carbon Storage."
Your suggestions and comments have played a crucial role in further improving and refining our research work. We sincerely appreciate the time and expertise you invested in the review process.
After receiving your feedback, we have made comprehensive revisions to the manuscript to address your suggestions and comments. We believe these improvements have significantly enhanced the quality of the manuscript and made it more complete..The point-by-point revision notes are as follows:
Suggestion 1: My main criticism is the clarity in certain areas, such as illustrations and some statements. For example, the abstract mentions INVEST, then PLUS, while the title refers to the INVEST-PLUS model. This can be a bit confusing. Please ensure that references are consistent throughout the document.
Response1：Thank you for your valuable feedback. Clarity of illustrations is indeed one of the issues with the paper, and I have worked to improve their resolution. The INVEST-PLUS model mentioned in the title refers to combining both approaches for the study. This expression is used in Chinese literature, but I agree with your suggestion to ensure consistent referencing throughout the document. I have removed the term from the title.
Issue 2: I also wonder if some clarification should be provided regarding land use and land cover—I assume that land use is the focus.
Response2：Thank you for your suggestion. As you mentioned, the focus of the study is land use. I had mixed up the concepts of land cover and land use. I have now revised the manuscript to appropriately remove references to land cover and concepts that are not directly related to the study.
Issue 3: The illustrations are good, but I am still unclear about some of the legends used. For example, in Figure 1—what is the color scheme, and what do the high and low references indicate? This also seems to conflict with the title of the reference study area map.
Response3：Thank you for your question. The name of the study area map primarily indicates its source, which is an official map provided by Guangdong Province in China. Since the study involves Hong Kong and Macau, it is important to use standardized maps to avoid sensitive issues related to the territory of the People's Republic of China. The base map of the Pearl River Delta provided by Guangdong Province only includes outlines and lacks topography. The color scheme is based on the colors used for plains and mountains on globes and the third-to-last color band provided by ArcGIS. This color scheme is also quite common in journals. If you have a better color scheme to suggest, I would greatly appreciate it. The high and low references were generated using DEM data analysis.
Suggestion 4: There are two Table 1s; I believe the second one should be Table 2. Additionally, there is a section at the end titled "Stock Hotspot Analysis." What is this? It seems unrelated to the text or tables.
Response4：Thank you for your careful observation. I apologize for the oversight; it should be "Carbon Stock Hotspot Analysis." I have corrected it. 214
Suggestion 5: In Figure 2, I think the color for farmland needs to be changed, and the illustration needs to be clearer.
Response5：Thank you for your suggestion. The clarity of Figure 2, as well as all the figures, does need improvement. I have adjusted the color for farmland.
Suggestion 6: The entire illustration should use a more standard north arrow instead of the default arrow provided by ESRI, which looks like it came from a pirate's treasure map.
Response6：Yes, your suggestion is excellent. The default arrow was indeed not very clear or aesthetically pleasing. I have changed it to a basic compass rose.
Suggestion 7: Please review each illustration carefully and consider how best to visually convey the information you are trying to communicate through the maps, such as cartography and color usage. This is crucial for readers to intuitively understand your analysis results. All maps also need some location information (annotations) and should be in a larger format.
Response7：Thank you for your suggestion. I have noticed the issue of unclear legends and have reprocessed some images by zooming in and improving resolution. Regarding the need for annotations on the maps, I initially considered this, but due to the large scope of the study, some maps like Figures 3, 7, and 5, which contain small patches, became obstructed by the text and were not intuitive. In Figure 9, the partitions are too detailed, and enlarging the font did not look good. Therefore, annotations are only displayed on Figures 1 and 4.
Suggestion 8: While the analysis is useful, how does it fit into a broader context regarding the implications of your findings and their relationship to agricultural planning, among other things? It might be interesting to consider how this study could potentially improve the current situation.
Response8：Thank you for your insight. It would be very cool if the theory could be applied in practice. Your suggestion has broadened my perspective, and I will focus more on this aspect in future research and writing.
We once again sincerely thank you for the support and guidance you have given to our research. We look forward to your valuable comments on the revised manuscript.
Warm regards,
ShuQi Huang；
DaFang Wu
Guangzhou University
Author Response File: Author Response.docx
Reviewer 3 Report
Comments and Suggestions for AuthorsThe main objectives of this paper are in the need of knowing what is happening with terrestrial carbon pools. It is of special interest to provide insights for improving cultivated land protection policies. Considering the importance of the are studied, the conclusions obtained are, in my opinion, of high interest.
Abstract presented mainly the conclusions of the study. The keywords should be arranged in alphabetical order and as a recommendation, try to use different words from those used in the title of the paper.
Regarding the introduction, I think that it is well planned. However, I disagree in part with this “There is a notable lack of studies specifically examining the effects of individual land types, particularly the balance of cultivated land occupation and compensation, on carbon storage”, because there are many works published about this issue. Moreover, I disagree with this one in lines 106-107: “Only a few scholars have addressed this aspect.”. I well know that there are some works done. Probably, not in China but in several countries, unless in Europe. As a suggestion, it would be desirable to have a look to the literature.
Materials and methods describe the research and it can be reproduced. However, I think that in section 3.4, this part “ (3) Model Parameter Configuration” should be revied in depth. For instance, check in line 304 “historical period from 2020 to 2015” and explain why “the neighborhood weight for the land type with the minimum expansion area is set to 0.1” (lines 311-212).
The results obtained are of great interest, as they reflect the dynamics of land occupation and the reduction of the possibilities of soil carbon storage. However, the basis of all this is citation [39], which we must assume is valid. That is, the coefficients indicated in Table 1 are assumed to be true. Perhaps this part of the study is a weakness, since it would possibly be necessary to carry out some criticism or verification of these coefficients. Even better explain how they were obtained, even if briefly.
It is well received that authors recognize the limitations of the study in the section Discussion. However, more limitations should be considered as the previous comment indicates.
Finally, I agree with conclusions. Normally I don't like them to appear in the form of a numbered list, but that's just a personal matter. However, I would like there to be a paragraph with a general conclusion of the study.
References should be improved as most of them are centred in China and several works, close to this done, can help authors and enrich the paper. Some recomendations (but they are not the only papers of interest):
https://doi.org/10.1111/gcb.14459
https://doi.org/10.1016/j.agee.2008.04.010
http://www.jswconline.org/content/57/4/196.abstract
Some minor changes in the format or minor mistakes should be considered.
For instance, spaces between words or marks. Examples in lines 16, 18, 22, 25 of the abstract (“.(“) or lines 55 (“evaluation.From”) and others (lines 68...). This happens in all the article.
Please review the references and try to follow the guide of style of the journal (the use of et al., and other minor mistakes regarding spaces between words and punctuation marks).
Please check the Table 1, at the down the table “ock Hotspot Analysis”
Please, consider to use the same type of letter in the equations, for instance check in equation 7
Understanding that it is very difficult to have good quality figures due to the large extension of analyzed, if authors can improve the quality of Figure 2 and Figure 7, it will be easy to understand the results. Figure 3 is easier to read.
Please, check the mistakes like this that appears in line 598 “4.2The regional”
Author Response
Dear Reviewer,
We sincerely appreciate you taking the time to review our paper despite your busy schedule. Your thorough feedback has been immensely valuable in helping us refine our research and enhance the overall quality of the manuscript. Not only have your insights guided us in making significant improvements, but they have also broadened our perspectives and deepened our understanding of the subject matter.
Thank you for your hard work and dedication throughout this review process. We have carefully considered each of your suggestions and made revisions accordingly. Below, we provide detailed explanations of the changes made to address your comments.
Suggestion 1: The keywords should be arranged in alphabetical order, and it is recommended to use words different from those in the paper's title whenever possible.
Response1：Thank you for your suggestion. This is a great idea. The term "carbon stock" has been modified to be different from the title. However, I believe that using the same terminology as in the title for "cultivated land requisition-compensation balance" maintains professionalism, so I did not make changes in that regard.34
Suggestion 2: Regarding the introduction, I think it is well-planned. However, I partially disagree with the statement, "There is currently a significant lack of specialized research on individual land types, particularly on the impact of the requisition-compensation balance of cultivated land on carbon storage," because there is a lot of literature on this issue. Additionally, I disagree with the sentence in lines 106-107: "Only a few scholars have studied this aspect." I am aware of several studies, possibly not in China, but in several countries, unless in Europe. As a suggestion, it would be best to review the literature.
Response2：Your suggestion is very accurate, and I agree with it. I realize that I haven't reviewed enough literature. In my research, I found that most studies focus on carbon emissions from cultivated land, while studies on carbon stock in cultivated land are less common. Clearly, it was wrong to draw such a conclusion without sufficient evidence. I have revised and reduced this statement. Thank you for your suggestion.
Suggestion 3: The materials and methods section describes the study well and makes it reproducible. However, I believe the section “(3) Model Parameter Configuration” in Section 3.4 should be thoroughly revised. For example, review line 304, “the historical period from 2020 to 2015.”
Response3：Thank you for your suggestion and correction. I have reviewed and revised the error in line 304. line278
Issue 4: Explain why the “neighborhood weight for the land type with the smallest expanded area is set to 0.1” (lines 311-312).
Response4：Thank you for your question. The setting of the neighborhood weight is based on references [40] and [38]. Reference [38] mentions that, in practical land use changes, even land types with a neighborhood weight of 0 can experience slight expansion. Therefore, setting the parameter to 0.1 takes real-world conditions into account. The highlighted area explains why it is set to 0.1.282-283
Issue 5: The results obtained are very interesting as they reflect the dynamics of land occupation and the potential reduction in soil carbon storage. However, the basis for all this is reference [39], and we must assume it is valid. That is, the coefficients shown in Table 1 are considered to be accurate. This part of the study might be a weak point, as it may require some critique or validation of these coefficients. It would be best to provide a brief explanation of how they were obtained.
Response5：Thank you for your suggestion. Yes, this is a limitation of the study, and I have addressed it as such in the subsequent discussion of the paper. Obtaining carbon stock coefficient data for different land types requires field sampling and extensive experimental validation, which is challenging in practice. Therefore, most studies rely on coefficients from other research. Since reference [39] specifically studies carbon stock in the Hong Kong-Zhuhai-Macao region and the coefficients have been corrected and validated, I have included an explanation of this in the paper and highlighted it. line211
Suggestion 6: The authors acknowledge the limitations of the study in the discussion section, which is well appreciated. However, as noted in previous comments, more limitations need to be considered.
Response6：Thank you for your suggestion. I have included the limitations of the carbon density coefficients in the third point of the discussion on research limitations.
Suggestion 7: Finally, I agree with the conclusion. Generally, I do not like it when conclusions are presented in a numbered list format, but that is just a personal preference. However, I would prefer to have a paragraph summarizing the general conclusions of the study.
Response7：Thank you for your suggestion. Presenting conclusions in a bullet-point format can make them more intuitive, and many references are presented in this way. However, I realize that this may be somewhat overly formalistic. I will consider this issue in future research.
Suggestion 8: The references should be improved, as most are focused on China. Some related papers could help the authors and enrich the content of the paper. Here are some suggestions (though these are not the only papers worth considering):
https://doi.org/10.1111/gcb.14459
https://doi.org/10.1016/j.agee.2008.04.010
http://www.jswconline.org/content/57/4/196.abstract
Response8：Thank you for your suggestions and the excellent papers you provided. I am pleased and honored that you recommended such valuable articles. I will download and thoroughly review these references, and I have already incorporated them into the manuscript. I believe this will significantly enhance the quality of the paper.594-595；616-617
Suggestion 9: Some minor formatting changes or errors should be considered, such as spaces between words or punctuation marks. For example, in the abstract, lines 16, 18, 22, and 25 (“.(”) or line 55 (“evaluation.From”), and other instances like line 68. This issue appears throughout the manuscript.
Response9：Thank you for your careful observation. I am embarrassed by my oversight. I am currently reviewing the manuscript thoroughly to avoid such minor errors.
Suggestion 10: Please review the references and try to follow the journal's style guide, including the use of "et al." and correcting other minor errors such as spaces between words and punctuation.
Response10：Thank you for pointing that out. Yes, I have noticed this issue and have revised the references accordingly, line by line.
Suggestion 11: Please review Table 1, specifically the “Hotspot Analysis” section below the table.
Response11：Thank you for your careful correction. I have made the changes.
Suggestion 12: Please consider using the same type of letters in the formulas, such as checking Formula 7.
Response12：Thank you for your careful observation and correction suggestion. I have made the necessary revisions.
Suggestion 13: Due to the large scope of analysis, it is challenging to produce high-quality charts. If the authors could improve the quality of Figures 2 and 7, the results would be easier to understand. Figure 3 is easier to read.
Response13：Thank you for your suggestion. The lack of clarity in the images is indeed a major issue in the paper. I have worked on improving this by increasing the image resolution and applying zoom to specific areas to enhance clarity.
Suggestion 14: Please check the error in line 598, where "4.2 Region" appears.
Response14：Thank you for your careful observation. The obvious errors in the words have been corrected.
We once again sincerely thank you for the support and guidance you have given to our research. We look forward to your valuable comments on the revised manuscript.
Warm regards,
ShuQi Huang；
DaFang Wu
Guangzhou University
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors
The revision seems properly addressed my recommendations. I have no further suggestions, and the paper can be considered for publishing.
With best regards
The reviewer
Author Response
Dear Reviewer,
Thank you for your review and feedback on our paper. We are pleased to know that the revised version appropriately addresses your suggestions. Your positive feedback is a great encouragement to us.
We greatly appreciate the valuable comments and support you provided during the review process, which helped us further refine the research. Your professional insights have significantly contributed to improving the quality of the paper.
Thank you once again for the time and effort you invested in the review process.
Best regards,
ShuQi Huang
Dafang Wu
Guangzhou University
Author Response File: Author Response.docx
