Assessing Spatial–Temporal Characteristics of Land Desertification from 1990 to 2020 in the Heihe River Basin Using Landsat Series Imagery
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsManuscript No. sustainability-3065426, titled “Assessing Spatial-Temporal Characteristics of Land Desertification from 1990 -2020 in the Heihe River Basin Using Landsat Series Imagery” focused on the utilization of high-resolution (30m) images to report the current situation on land desertification and restoration in the Heihe River Basin, China within three interval periods (1990-2000, 2000-2010, and 2010-2020). The study is important for the decision-makers to determine the priority of reclamation and restoration of the desert area. My comments are listed below:
1- In the abstract, the abbreviation “HRB” appeared suddenly without interpretation, please for the first appearance of abbreviation please write a full description, and the same tendency with “EWDP” and other abbreviations throughout the manuscript (e.g., UNCCD, NDVI, MSAVI, EVI, etc).
2- Please check the following words, jeopardize, offset, surge, steppe, barren, roughly, permafrost to thaw, aggravating, on the one hand, withering, curb,
3- What do you mean by “middle and lower reaches” in line 179?
4- In Table 1, the “Secondary types” I think "and” is missing (e.g., Paddy field, and Non-paddy field), please check all items.
5- Lines 185-186, were repeated previously in Lines 172-173, please check.
6- Line 211, “2010, 2020, and 2020”, the year 2020 repeated twice, please check.
7- Table 2, Please check the distances of the rule and reference index threshold.
8- Please check “table 4” line 298, I think it is better to write it as Tables 4-6.
9- Line 303, what do you mean by “Other”?
10- Line 367, I did not understand “undergoing is”.
11- Line 369, add a citation after “in the previous period”.
12- The manuscript is filled with abbreviations, accordingly Table of abbreviations should be incorporated.
13- Line 440, please check “with in”.
14- Please check lines 512-513.
15- Lines 512-516, please add a citation.
16- Lines 544-548, please add a citation.
17- Figure 6b, please add the name of “sheep” on the Figure.
18- Line 563, “and” should be added in the middle of the sentence.
19- In conclusion, please check line 586.
Comments on the Quality of English Language
Moderate editing of English language required
Author Response
We would like to express our gratitude to the reviewers for their valuable feedback on our manuscript. We have invited native English speakers to address the language issues highlighted by the reviewers. The specific changes suggested are as follows:
Comments 1: In the abstract, the abbreviation “HRB” appeared suddenly without interpretation, please for the first appearance of abbreviation please write a full description, and the same tendency with “EWDP” and other abbreviations throughout the manuscript (e.g., UNCCD, NDVI, MSAVI, EVI, etc).
Response 1: The full form of all abbreviations used in the manuscript has been provided for the first time in their appearance.
Comments 2: Please check the following words, jeopardize, offset, surge, steppe, barren, roughly, permafrost to thaw, aggravating, on the one hand, withering, curb,
Response 2: The text has been revised and edited by professionals to address language issues.
Comments 3: What do you mean by “middle and lower reaches” in line 179?
Response 3: “middle and lower reaches” refers to the midstream and downstream regions of the HRB, and change in the manuscript.
Comments 4: In Table 1, the “Secondary types” I think "and” is missing (e.g., Paddy field, and Non-paddy field), please check all items.
Response 4: Modified as suggested.
Comments 5: Lines 185-186, were repeated previously in Lines 172-173, please check.
Response 5: Checked and modified.
Comments 6: Line 211, “2010, 2020, and 2020”, the year 2020 repeated twice, please check.
Response 6: Modified as suggested.
Comments 7: Table 2, Please check the distances of the rule and reference index threshold.
Response 7: Checked and modified.
Comments 8: Please check “table 4” line 298, I think it is better to write it as Tables 4-6.
Response 8: Modified as suggested.
Comments 9: Line 303, what do you mean by “Other”?
Response 9: The term "Other" is used to describe the remaining land use types that are not classified as NDL or DL and is described in line235-237.
Comments 10: Line 367, I did not understand “undergoing is”.
Response 10: The text has been revised and edited by professionals to address language issues
Comments 11: Line 369, add a citation after “in the previous period”.
Response 11: The term "in the previous period" refers to the preceding period of this study and therefore does not necessitate the inclusion of a citation.
Comments 12: The manuscript is filled with abbreviations, accordingly Table of abbreviations should be incorporated.
Response 12: The modification was made in accordance with the recommendations set forth in section 1.
Comments 13: Line 440, please check “with in”.
Response 13: The text has been revised and edited by professionals to address language issues
Comments 14: Please check lines 512-513.
Response 14: The information was verified and found to be accurate.
Comments 15: Lines 512-516, please add a citation.
Response 15: Relevant references have been added
Comments 16: Lines 544-548, please add a citation.
Response 16: Relevant references have been added
Comments 17: Figure 6b, please add the name of “sheep” on the Figure.
Response 17: Modified as suggested.
Comments 18: Line 563, “and” should be added in the middle of the sentence.
Response 18: Modified as suggested.
Comments 19: In conclusion, please check line 586.
Response 19: Relevant references have been added.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe article's topic, desertification patterns in China, is highly significant, particularly in the context of climate change. The research's value is obvious; the authors explored satellite images and deeply analysed the land use changes that have appeared in the last 30 years in the Heike River basin (HRB). The results are presented clearly and in detail. However, adjustments must be made to enhance the article's scientific relevance.
While the land use changes are extensively commented on, the causes are only mentioned in the disscussin sectior. It would be more interesting to include in the actual analysis and obtain some results in the following directions:
1. To map and (spatially) correlate the pressures to the desertification process: for example, precipitation changes, i.e. diminution (and maybe also temperatures), do they overlap the areas where the desertification processes also occurred? Overgrazing and overexploitation of agricultural areas do they also overall other desertification expansion areas. What is the mixture between the natural and the anthropogenic factors when we discuss the desertification process in these geographic areas? I think such an assessment would increase the current paper's value and provide more insights into a matter of such great importance.
2. To make some predictions (based on the factors presently inducing land use changes) regarding the areas subject to future desertification processes. Some scenarios could be imagined (from the best to the worst-case scenario).
Adding these two analyses to the current study would be a real benefit, and the article could be an important reference in the field.
Comments on the Quality of English Language
The are some things that could be improved regarding the use of English. A general but careful proofreading should be done.
Author Response
We would like to express our sincerest gratitude to the reviewers for dedicating their time to provide us with such invaluable feedback on our manuscript. Furthermore, the reviewers observed that the manuscript provides only a preliminary investigation into the underlying causes of desertification. However, the objective of this study was to examine the process of watershed desertification from the perspective of land cover change. This approach facilitates the integration of desertification monitoring methods, such as vegetation change and visual interpretation. This should enhance our ability to provide more detailed insights into desertification. Given that this study does not focus on the drivers of desertification, we have only analyzed the factors that may lead to the development and reversal of desertification in the discussion section.
Comments 1:To map and (spatially) correlate the pressures to the desertification process: for example, precipitation changes, i.e. diminution (and maybe also temperatures), do they overlap the areas where the desertification processes also occurred? Overgrazing and overexploitation of agricultural areas do they also overall other desertification expansion areas. What is the mixture between the natural and the anthropogenic factors when we discuss the desertification process in these geographic areas? I think such an assessment would increase the current paper's value and provide more insights into a matter of such great importance.
Response 1: The reviewers discussed the mapping of the effects of precipitation and temperature changes on desertification, as well as the potential correlation between these changes and the development and reversal of desertification. However, for reasons of confidentiality, meteorological data for the basin area are not available. Consequently, we were only able to select data from meteorological stations with climatic characteristics representative of the different regions of the basin to illustrate trends in climate change in the basin. Furthermore, although some meteorological data products can provide data covering the entire basin, their coarse resolution does not meet the requirements of basin-scale analyses.
Distinguishing between the effects of natural and anthropogenic factors on desertification has always been a difficulty in desertification research. In the Black River Basin in particular, its unique geographical unit makes it even more difficult.
Data show that the number of livestock in the basin has continued to increase, but it is difficult for us to determine the number of livestock grazing on natural grasslands due to the government's implementation of grazing bans and roundups in recent years.
Cultivation of arable land inevitably reduces the amount of desertified land. Because of the limited surface water resources in the basin, the overcultivated land must use a lot of groundwater to meet irrigation needs, lowering the regional groundwater table and reducing much of the vegetation that depends on groundwater for survival. When water-saving irrigation is adopted, the construction of water-saving canals reduces the source of groundwater recharge, which also degrades the vegetation in the transition zone between oasis and desertification. Therefore, we can only illustrate the possible impacts of climate change and human activities on desertification in the discussion section, and it is difficult to specify the actual location.
Comments 2: To make some predictions (based on the factors presently inducing land use changes) regarding the areas subject to future desertification processes. Some scenarios could be imagined (from the best to the worst-case scenario).
Response 2: The reviewers have referred to specific predictions regarding future desertification. However, the mere act of making predictions about desertification lacks evident scientific significance. Instead, a comprehensive section on predictions of desertification would occupy a considerable portion of the paper, which is not the principal objective of this study.
Given the recent expansion of cropland in the basin and the inevitable changes in terrestrial water storage due to climate change and extensive irrigation, the next step will be to reduce the scale of the GRACE data to facilitate the study of changes in terrestrial water storage at more favorable scales and to elucidate the effects of climate change and expansion of cropland on changes in terrestrial water storage. In addition, projections of future terrestrial water stocks under different greenhouse gas emission scenarios will be made, as well as projections of future desertification in the basin.
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors provided some pertinent arguments regarding the issues that I proposed. I understand now that some limitations cannot be overcome within this study (most of them related to the availability of data). Also, the new version of the article looks better, as the authors improved the clarity of the content and addressed some formatting issues. Acknowledging these, we agree that the article can be published as such in the Sustainability journal.
Comments on the Quality of English LanguageThe article still needs some minor English language adjustments. Careful supplementary proofreading should be taken into account.
