Round 1

Reviewer 1 Report

This paper mainly analyzes and discusses the ecological and environmental factors of the Qinling Mountains. There are some issues that need to be carefully addressed.

1. The introduction should add the latest research literatures in the ecological and environmental factors of the Qinling Mountains.

2. In the discussion section, more factual evidence should be added to verify the correctness and effectiveness of the experimental analysis results.

3. In the experimental section, comparative experiments with other methods are added to verify the sophistication of the proposed method.

Author Response

Response to Reviewer 1 Comments

1. The introduction should add the latest research literatures in the ecological and environmental factors of the Qinling Mountains.

Response: Thank you for your valuable feedback on the paper. We have carefully considered your suggestions and made revisions to the introduction, incorporating the latest research literature on ecological and environmental factors in the Qinling mountains. We believe that these additional contents will better support the scientific validity and innovation of this study. Please see line 81-92 for details.

2. In the discussion section, more factual evidence should be added to verify the correctness and effectiveness of the experimental analysis results.

Response: We appreciate your insightful comments on the discussion section of our manuscript. In accordance with your suggestions, we have enhanced the section by incorporating additional content to substantiate the veracity of our findings.

Regarding qualitative assessment, we have drawn comparisons between the spatial distributions of the ecological environment as characterized by the Ecological Index (EI) and RSEI approaches. For quantitative validation, we have integrated data from field surveys conducted by our team in the Qinling Mountains in 2023. This integration serves to affirm the accuracy and reliability of our evaluations based on the RSEI method.

We have included comprehensive statistical tables that furnish these new pieces of evidence in Supplementary Table S1 for your convenience. For further details, please refer to line 445-455 in the manuscript.

3. In the experimental section, comparative experiments with other methods are added to verify the sophistication of the proposed method.

Response: Thank you for your insightful feedback on the experimental section of our paper. Following your recommendations, we have adopted an additional methodology, the widely recognized Ecological Index (EI), for assessing the quality of the ecological environment. We have detailed its inception, underlying principles, and its application specifically within the Qinling region. The evaluation results utilizing EI for this area are principally drawn from established studies in the current literature. By adding a comparison with the EI evaluation results, we try to illustrate the complexity and advancement of the proposed RSEI in this study. Please see line 161-187 for details.

The other revisions in the text have been highlighted in red for your review. Thank you once again for your assistance with the manuscript.

Author Response File: Author Response.doc

Reviewer 2 Report

Paper sustainability-2938111 analyzes the Qinling mountains via the Google Earth Engine and Landsat images, constructing Remote Sensing Ecological Index for quantitatively analyzing the spatiotemporal evolution of the ecological environment quality from 1990 to 2020. The ideas and contents of the paper are clear and easy to understand, but improvements are needed in the following areas.

1. The paper lacks a thorough discussion of the limitations of the remote sensing data used for the analysis, including inaccuracies and resolution limitations.

2. Additionally, a comparative analysis with similar studies on in other mountainous regions could have enriched the discussion and provided broader insights.

3. Lacks detailed discussion on potential future research directions and areas.

None.

Author Response

Response to Reviewer 2 Comments

1. The paper lacks a thorough discussion of the limitations of the remote sensing data used for the analysis, including inaccuracies and resolution limitations.

Response: Thank you for your valuable comments on our manuscript. We have addressed the limitations of remote sensing data analysis in the paper with a detailed discussion and explanation.

In the discussion section, we analyzed how differences in the timing of image acquisition might affect our RSEI assessment outcomes. Moreover, we discussed the limitations of the method we commonly employ for acquiring larger area images under cloud influence, which typically involves using images from the two nearest years for computation. We also examined the application of MODIS data with its shorter revisiting period and the limitations imposed by its spatial resolution.

Finally, we explored potential solutions, such as more advanced image data preprocessing techniques. Please see line 456-470 for details. We hope that these improvements will meet with your approval.

2. Additionally, a comparative analysis with similar studies on in other mountainous regions could have enriched the discussion and provided broader insights.

Response: Thank you for your valuable comments on our paper. We completely agree with your suggestion to compare our study with similar research conducted in other mountainous regions to enrich the discussion and provide a broader perspective, and we have added relevant content to the revised paper.

We have conducted a literature search and identified several studies carried out in mountainous areas, such as the Erhai Lake basin in Yunnan, China, Lake Taihu, Wugong Mountain, Zijin Mountain, Qilian Mountains, and others. In these studies, we found conclusions similar to those in our research, indicating that factors such as altitude, human activity, and ecological protection policies have a considerable impact on environmental quality.

By comparing the results of these studies with our research, we can better discuss the characteristics of the ecological quality in the Qinling region and understand its universality and uniqueness within the global context of mountain ecosystems. Please see line 433-443 for details.

3. Lacks detailed discussion on potential future research directions and areas.

Response: Thank you for your valuable comments on our paper. In the revised manuscript, we have supplemented it with a discussion on potential future research directions.

In the discussion section, we first address how to further improve remote sensing technology to enhance the quality and resolution of image data, such as employing the Continuous Change Detection and Classification (CCDC) technique. We also consider the integration of multi-source data as a potential avenue to achieve large-area ecological assessments with short revisit period.

Furthermore, we discuss the refinement of the RESI to more accurately reflect the ecological environment quality. For instance, the precision of the RSEI could be increased by optimizing and improving the algorithms of the four indices that compose it, such as the LST. Additionally, introducing new spatial information, such as Net Primary Productivity (NPP) and water-related data, could help to establish a more comprehensive evaluation system and enhance future ecological quality assessments. Please see line 468-474 and 476-493 for details.

The other revisions in the text have been highlighted in red for your review. Thank you once again for your assistance with the manuscript.

Author Response File: Author Response.doc

Reviewer 3 Report

The reviewed paper is an example of a high-quality GIS supported research. It is systematic, following the IMRAD structure and coherent in its text. All parts are systematically developed and linked to each other. Majority of the sources used were published in the last five years, making them recent in their message. There are some minor suggestions from my part to upgrade it to be more understandable to the wider audience. Therefore, here are general suggestions:

1.       The keywords are sensibly selected, but I suggest adding some regional names (e.g. Qinling mountains, China).

2.       Provide a larger-scale regional setting map that will show the study area. Where exactly is the study area located on the country level? Additionally, add all the places’ names from the text to this map, so that the reader can easily link the message with the space. Thirdly, correct the legend so that the polygon elements are above the raster ones. Also, make the scale of the same size on all the maps (I suggest 100 km).

3.       When mentioning a table or figure for the first time, add that table/figure immediately.

4.       Think of adding a workflow image to the Materials and Methods section. It would make reading the text even more understandable.

5.       Add a sensible concluding remark on the importance of such studies to the end of the conclusion (since of course such studies are of vast importance to the policy makers and others).

6.       Go through the text and edit the font sizes, formulas (some are in italics, the others in bold, some nothing of that).

In the continuation, I prepared a line-by-line suggestions list for the improvements.

Comments for author File: Comments.docx

There are some minor corrections required. I wrote the suggestions in the attached document. However, the text is on a very high English language level.

Author Response

Response to Reviewer 3 Comments

1. The keywords are sensibly selected, but I suggest adding some regional names (e.g. Qinling mountains, China).

Response: Thank you for your feedback on the selection of keywords for the paper. We have added regional names such as “Qinling mountains, China” to the keywords as your suggestion.

2. Provide a larger-scale regional setting map that will show the study area. Where exactly is the study area located on the country level? Additionally, add all the places’ names from the text to this map, so that the reader can easily link the message with the space. Thirdly, correct the legend so that the polygon elements are above the raster ones. Also, make the scale of the same size on all the maps (I suggest 100 km).

Response: Thank you for your feedback on the map presentation. We have made the following changes as per your suggestions:

1) We have added a larger regional setting map to show the study area’s location within the country. Please see Figure 2 and 5 for details

2）We have included the names of all places mentioned in the text on the map for easy reference by the reader. 

However, the boundaries of the Qinling protected areas, which include general protection area, key protection area, and core protection area, are classified and cannot be disclosed publicly.

Therefore, we have provided a diagram from the official website, along with a concise translation, strictly for reference. For additional information, please see Figure S1.

Similarly, the ecological function areas are also the data used for our driving force analysis, which do not fall under the category of data that requires detailed analysis of their spatial distribution patterns. Therefore, they are included in the Supplementary Materials, with the mapping details available in Figure S2.

3) We have adjusted the legend to ensure that polygon elements are above raster elements.

4) We have ensured that all maps have the same scale size (100 km).

We are looking forward to your further review and hope that these changes meet with your approval

3. When mentioning a table or figure for the first time, add that table/figure immediately.

Response: Thank you for your suggestion. We have rearranged the order of the tables and figures to ensure that when a table or figure is mentioned for the first time, it is immediately presented.

4. Think of adding a workflow image to the Materials and Methods section. It would make reading the text even more understandable.

Response: Thank you for your suggestion. We have added a workflow image to the Methods and Materials section. Please see Figure 1 for details. This figure provides a detailed depiction of the key steps and processes in our study, which will help readers to more intuitively understand our research methodology. 

5. Add a sensible concluding remark on the importance of such studies to the end of the conclusion (since of course such studies are of vast importance to the policy makers and others).

Response: Thank you for your insightful review of the conclusion section of the paper. We have addressed your suggestion by adding a reasonable concluding remark on the importance of such studies. We have highlighted the significant impact of ecological protection measures and the expansion of vegetation cover on the ecological quality of the Qinling region. We have also emphasized the necessity of continuous monitoring for the sustainable development of this critical ecological zone. These insights provide a scientific foundation for the protection of the ecological environment and the promotion of high-quality development in the Qinling region. Please see line 520-526 for details.

6. Go through the text and edit the font sizes, formulas (some are in italics, the others in bold, some nothing of that).

Response: Thank you for your suggestions. We have reviewed and revised the text and formulas to ensure they meet the specified requirements.

In addition, thank you for your line-by-line suggestions for my paper. We have compiled your questions below and addressed them one by one.

7. 14 I suggest changing ‘necessitating’ into (→) needing.

Response: Thank you for your suggestions. We have revised it. Please see line 14 for detail.

8. 23: a space is missing in front of and.

Response: Thank you for your suggestions. We have revised it. Please see line 24 for detail.

9. 25: factors → forces

Response: Thank you for your suggestions. We have revised it. Please see line 25 for detail.

10. 28-30: Think of changing the text in the following way: … Qinling region, making this study a scientific reference for providing ecological environment protection and promoting high-quality development.

Response: Thank you for your suggestions. We have revised it. Please see line 29-31 for detail.

11. 36: …and serves (besides the historical development)…

Response: Thank you for your suggestions. We have revised it. Please see line 38-39 for details.

12. 39: effectively → effective

Response: Thank you for your suggestions. We have revised it. Please see line 41 for detail.

13. 43: space [3]

Response: Thank you for your suggestions. We have revised it. Please see line 45 for detail.

14. 45-46: have been OF widespread use

Response: Thank you for your suggestions. We have revised it. Please see line 48 for detail.

15. 49: etc. is not necessary

Response: Thank you for your suggestions. We have revised it. Please see line 51 for detail.

16. 50: brackets [8])

Response: Thank you for your suggestions. We have revised it. Please see line 52 for detail.

17. 53: comprehensive and (semi-)automatic? Think of adding this perhaps.

Response: Thank you for your suggestions. We have revised it. Please see line 55 for detail.

18. 57: soil → pedological

Response: Thank you for your suggestions. We have revised it. Please see line 59 for detail.

19. 58: security → stability

Response: Thank you for your suggestions. We have revised it. Please see line 60 for detail.

20. 59: no comma in front of and in this case

Response: Thank you for your suggestions. We have revised it.

21. 62, 66: source missing

Response: Thank you for your suggestions. We have revised it. Please see line 65 and 68 for details.

22. 68: Shaanxi government? Or Who?

Response: Thank you for your suggestions. We have revised it. Please see line 71 for details.

23. 72, 73: no commas

Response: Thank you for your suggestions. We have revised it. 

24. 80: and ARE with

Response: Thank you for your suggestions. We have revised it. Please see line 94 for details.

25. 81: I suggest using the past tense in this case: selected

Response: Thank you for your suggestions. We have revised it. Please see line 95 for details.

26. 82: to investigate

Response: Thank you for your suggestions. We have revised it. Please see line 97 for details.

27. 83: 30 years IN THE AREA

Response: Thank you for your suggestions. We have revised it. Please see line 98 for details.

28. 83: analysed

Response: Thank you for your suggestions. We have revised it. Please see line 98 for details.

29. 84: in ITS ecological

Response: Thank you for your suggestions. We have revised it. Please see line 98 for details.

30. 85: The aim OF THE ARTICLE is (i)…, (ii)…, and (iii)…

Response: Thank you for your suggestions. We have revised it. Please see line 99-102 for details.

31. 90: focus → focuses/focused

Response: Thank you for your suggestions. We have revised it. Please see line 114 for details.

32. 93: Han River – add such names to the regional setting map

Response: Thank you for your suggestions. We have revised it. Please see Figure 2 for details.

33. 1.: add sources for all the information on temperature… Also, briefly describe geological and geomorphological setting.

Response: Thank you for your suggestions. We have revised it. Please see line 120-124 and 128 for details.

34. 103: brown earth is not a precise name nor a soil type, please correct it. What is broader distribution on the southern slope?

Response: Thank you for your suggestions. We have revised it. Please see line 131-132 for details.

35. 113 was → were

Response: Thank you for your suggestions. We have revised it. Please see line 142 for details.

36. 117-124: why have you put the links here? I suggest moving them to the References section

Response: Thank you for your suggestions. We have revised it. Please see line 149 and151-154 for details.

37. 132: repeat the source of the RSEI

Response: Thank you for your suggestions. We have revised it. Please see line 191 for details.

38. Equation 1: Is it possible to make the acronyms in the equation more understandable

Response: Thank you for your suggestions. We have revised it. Please see line 194-195 and Table 1 for details.

39. 151-159: Start explaining from the beginning of the equation.

Response: Thank you for your suggestions. We have revised it. Please see line 211-216 for details.

40. 157: ‘‘interacion was an interaction’’ – this is a circular definition. Revise it.

Response: Thank you for your suggestions. We have revised it. Please see line 217-218 for details.

41. 169-172: why in bold?

Response: Thank you for your suggestions. We have revised it. Please see line 231-233 for details.

42. 173: I suggest renaming the title into ‘Results and Analysis’ since it encompasses lots of analysis, which is a good thing.

Response: Thank you for your suggestions. We have revised it. Please see line 235 for detail.

43. 1.1.: the name of the subsection is missing

Response: Thank you for your suggestions. We have revised it. 

44. were shown → are shown

Response: Thank you for your suggestions. We have revised it. Please see line 237 for detail.

45. 180: what was the criteria for the classification? Make a reference if you explained it elsewhere.

Response: Thank you for your suggestions. We have revised it. Please see line 243 for detail.

46. 182: one space too much

Response: Thank you for your suggestions. We have revised it. 

47. Figure 3: make one scale, one legend and one arrow. Make the text on the legend larger.

Response: Thank you for your suggestions. We have revised it. Please see Figure 5 for detail.

48. 225: Can you show the mentioned protected areas on a location map or somewhere else? The same for the cities and districts. Namely, it is difficult to distinguish between general, key and core protected areas.

Response: Thank you for your suggestions. Regrettably, as we have explained previously, the vector boundaries of the protected area are classified data, and we can only provide a schematic diagram from the official website without latitude and longitude coordinates in the Supplementary Materials. We appreciate your understanding. The positions of other cities have been indicated on the map accordingly, please see Figure 2, 3 and 5 for details.

49. Table 2: Is it possible to visualizethat?

Response: Thank you for your suggestions. However, due to the significant variation in area proportions within the table, visualizing this data in a chart might make it challenging to represent the smaller areas clearly. In contrast, the table format provides a more intuitive presentation of the varying sizes and proportions of the different categories. For this reason, we believe that retaining the tabular format is more suitable for this data. I am looking forward to your further review and hope that this explanation addresses your concern.

50. Figures 4 and 5: Make the fonts bigger.

Response: Thank you for your suggestions. We have revised it. Please see Figure 6 and 7 for detail.

51. Table 3: Land use with a capital letter (L)

Response: Thank you for your suggestions. We have revised it. Please see Table 2 for detail.

52. Figure 6: I realizethat you explained the factors in Table 3, but add a legend here as well.

Response: Thank you for your suggestions. We have revised it. Please see Figure 8 for detail.

53. 319: which human activities? Name them and add a source.

Response: Thank you for your suggestions. We have revised it. Please see line 387-388 for details.

54. 323: processed? Think of another more suitable expression. Additionally, add a source, which is missing.

Response: Thank you for your suggestions. We have revised it. Please see line 392 for details.

55. 326: Source missing

Response: Thank you for your suggestions. We have revised it. Please see line 396 for details.

56. 337: a typo (.)

Response: Thank you for your suggestions. We have revised it. Please see line 406 for details.

57. 338: Cui’s – a space too many

Response: Thank you for your suggestions. We have revised it. Please see line 407 for details.

58. 352-355: I suggest citations here to boost credibility

Response: Thank you for your suggestions. We have revised it. Please see line 414-417, 424 and 426 for details.

59. 387: show these cities on the map

Response: Thank you for your suggestions. We have revised it. Please see Figure 2 and 5 for details.

60. Source 25: NDVI with capitals perhaps? A space before ‘in Chinese’

Response: Thank you for your suggestions. We have revised it. 

The other revisions in the text have been highlighted in red for your review. Thank you once again for your assistance with the manuscript.

Author Response File: Author Response.doc

Round 2

Reviewer 1 Report

The authors have well addressed all my comments. I have no more concerns.