Review Reports - Spatial–Temporal Changes and Driving Forces of Sandy Desertification in Dengkou County, China, Based on Refined Interpretation and Validation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Desertification is a serious ecological, economic and environmental problem worldwide. The manuscript selects a county on the edge of the East Asian desert in China - Dengkou County as the case area to carry out the study, using multi-period remote sensing image data and refined interpretation methods to explore the spatiotemporal evolution trend and driving factors of desertification in Dengkou County. However, there are still areas for improvement in the manuscript. The specific construction suggestions are as follows:
1. In the introduction, the focus on the problem to be addressed by the manuscript needs to be further refined.The authors pointed out at least the following aspects of knowledge gaps to be addressed, such as the selection of desertification monitoring indexes, driver factor analysis, and spatiotemporal variation indices (e.g., intensity).
First, in terms of monitoring methods, after mentioning many of the previous desertification monitoring indicators, the author goes on to mention that "although visual interpretation methods are time-consuming and labor-intensive, they are highly accurate and play a vital role in desertification research." "The first is the selection of desertification monitoring indicators, and the second is visual interpretation, and the logic before and after is puzzling. It is suggested that the contributors should adopt a taxonomic approach to desertification based on visual interpretation and validation, thus complementing the shortcomings of existing studies based solely on a few indicators.
Second, in terms of driving factors, the contributors mentioned that meteorological factors are the key drivers of the formation and development of sandy lands. Environmental factors such as topography, soil type, and soil moisture also play an important role in the formation of desertification. In addition, factors such as population density, GDP, nighttime sunlight and livestock density also play a role in the development of desertification. In addition, few existing studies have touched on the driving effect of geological conditions on desertification, and the impact of geological processes on the development of desertification is still unclear. Geological factors are placed in an important position here, and from the following, only geological factors are taken into account. Therefore, it is necessary to pay attention to the accuracy of words and expressions, and here it is necessary to put the geological factors in a reasonable position. Moreover, the argument focuses on the importance of driving factor analysis, rather than the special importance of geological factors.
Thirdly, the author then mentions the role of intensity analysis in the analysis of land change. From the reviewer's point of view, it is considered that this issue is given in the research methodology and does not need to be emphasized in the introduction.
After describing the above three aspects, the author gives the research purpose of the manuscript. It is believed that the matching between the discussion in the previous introduction and the research purpose needs to be further improved and optimized.

2.The rationale for the conclusions of the study needs to be strengthened. For example, in terms of driving factors, the contributors mentioned meteorological factors as key drivers of the formation and development of sandy lands. Environmental factors such as topography, soil type, and soil moisture also play an important role in the formation of desertification. In addition, factors such as population density, GDP, nighttime sunlight and livestock density also play a role in the development of desertification. In addition, few existing studies have touched on the driving effect of geological conditions on desertification, and the impact of geological processes on the development of desertification is still unclear. However, in the paper, it is believed that meteorological factors have a moderate degree of driving force, and it is necessary to explain the reasons for the differences, and whether there is a correlation with the time scale of the study? For example, in a longer period of time, arid climate has a core driving factor, and in a relatively short period of several decades, human activities such as grazing, farming, ecological construction, and urban development have more significant driving effects?

Author Response

Dear Reviewer, Thank you for taking the time to review my submission. Your suggestions have helped make the content of the article more comprehensive and rigorous. I have detailed my modifications in the attached PDF. Thank you again for your valuable feedback. Sincerely, Author

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors,

Thank you for the opportunity to review your manuscript. The study offers information on the temporal and spatial changes of sandy desertification, which is valuable for ecological restoration and desertification control.

I have made my comments for your consideration in the attached annotated document.

Thank you,

Reviewer

Comments for author File: Comments.pdf

Author Response

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The study addresses desertification, a relevant environmental issue that particularly affects arid regions. It presents a study of spatial and temporal changes, as well as the factors that influence this process, in a sandy desertification area in Dengkou, using satellite imagery and field validation.

The paper follows a logical structure, beginning with a well-written abstract that effectively introduces the research. However, I believe it would be worthwhile to add the country's name to the title and keywords, which places the reader in a broader context. Furthermore, the results are presented in the abstract in an unusual way; I suggest creating a more fluid description.

The introduction is well-organized and provides a comprehensive overview of desertification. The choice of Dengkou County is well-founded, based on its characteristics and environmental challenges. However, I find some parts repetitive, which could be summarized and removed to later paragraphs. For example, the section between lines 103 and 113 could be summarized and moved to the first part of the introduction, complementing the text up to line 56. Furthermore, there are some abrupt transitions in the introduction. The text up to page 71 describes sandy desertification, and from line 72 onward, remote sensing methods begin to be discussed. Next, in line 102, the factors influencing sandy desertification are discussed again. This could be revised. As previously reported, in lines 80, 89, 93, and others, the references need to be verified. In other papers in this journal, references are presented only with the number and not the author's name.

The methodology is well described, providing detailed information on aspects such as obtaining remote sensing data, influence data, as well as the identification, classification, and validation of lands with sandy desertification. Tables 3 and 4 are very interesting. However, details about the study area are lacking. The geological characteristics of the region could be described, as well as demographic data (population/economy) about the region (the city of Bayannur is not mentioned in the text. What is its population?). The text describes geological conditions and soil type as important drivers of the desertification process, but there is no description of these parameters in the region. Furthermore, some equations and methods lack bibliographic references.

Line 159 presents an annual river flow value; however, I believe this value could be presented in m³/s, as it is the most commonly used flow unit and provides a better basis for comparison for the reader.

The use of 176 field points could be more detailed (What were the criteria used for their selection? What were the distribution and sampling criteria?). Furthermore, some of the equations and methodological procedures would benefit from appropriate bibliographical references to confirm their validity and clarify their origin. All these issues are described in the attached pdf.

The results and discussion are presented objectively and meet the proposed objectives. However, I believe it is important to describe in more detail the factors that helped reduce the desertification process and not just present statistical data. For example, the text describes livestock density, GDP, geological conditions, and other factors as drivers of the reduction in desertification, but no figures are presented to support this assertion. It would be interesting to describe that livestock density decreased from XX to YY over the analyzed period, as well as explain why this happened. The same applies to GDP.

Furthermore, the results and discussion require a more precise description of cause and effect. Line 330 describes " indicating that the degree of sandy desertification in the SDA intensified from the Hetao Plain toward the Ulan Buh Desert” but the reasons why this occurred are not explained.

Lines 434 to 446 describe the driving forces behind sandy desertification, reporting that livestock density, GDP, geological conditions, and other factors acted as drivers of desertification reduction, but no numbers are presented to support this claim. It would be interesting to present numbers for these parameters over the analyzed period to allow an assessment of their importance in the context of desertification reduction. Another unclear issue is how geological conditions have contributed to reducing desertification, given that, in reality, these conditions have not changed over the past four decades.

Section 4.2 describes several projects that have contributed to reversing the sandy desertification process. I believe that more details on the practices and methodologies adopted in these projects could be described, as this gives the reader a better understanding of the processes that led to the reduction of desertification and the possibility of implementing these measures in other regions of the world. For example: Reforestation, which is a very important practice for reversing sandy desertification, is only mentioned twice in the text. All these issues are described in the attached pdf.

The conclusions are aligned with the paper's context and assertively summarize the findings, presenting proposals for future interventions.

Comments for author File: Comments.pdf

Author Response

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Dear authors,

Thank you for your work.

Please find my comments and suggestions in the attached pdf file.

Good luck

Comments for author File: Comments.pdf

Author Response

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

After the revision of the author's team, the quality of the manuscript has been significantly improved. There are still some detail deficiencies in the manuscript, and it is recommended to further improve it.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear authors,

Thank you so much for your revised version.

Although I have some minor points:

1- I still see that a study area description should be separated and adjusted under a main title.

2- Although figures were enhanced, some issues are arising (coordinates are not readable in figure 1, and figures in figure 2 are not indicated by any marks to give an impact to readers.