Multi-Scenario Simulation of Land-Use Change and Delineation of Urban Growth Boundaries in County Area: A Case Study of Xinxing County, Guangdong Province

Round 1

Reviewer 1 Report

The reviewed article presents simulations and analysis of possible trends in the development of land use in a selected administrative unit. It is a typical example of simulation analyzes using one of the prediction methods on a newly selected area under certain restrictions. The distinguishing element of the conducted research is the size of the analyzed area and the adopted assumptions and limitations in line with the current regional policy. However it is difficult to fully assess the correctness of the calculations made because of poor quality of illustrative material attached to the article (at least in my wersion of generated pdf file). Therefore:

1. The Authors should include high resolution maps and figures with clearly visible legends, labels and additional descriptions on all figures.

2. The model validation is highly discussable. If I understand well, the Authors biult the model for LULC changes simulation on the basis of data from 2015 and 2020. Then the prediction is prepared for 2020 and it is compared to obserwed from 2020 . If it is the same data set which had been used before for model construction then it is no wonder that the matching of the simulation to the existing state is high, and thus the model accuracy is high. The simulation should be generated for another time period and validated on other data set, for example from 2022.

3. It is discusable that model of changes is constructed on the basis of 5 years changes, and then simulated LULC changes time period is 15 years long.

4. It is not clearly presented how the "Three-line scenario Coordination" for 2035 was developed.

5. Due to the slight changes observed and simulated for the entire area except for two sub-regions, it may be considered whether to conduct the entire analysis only for these two sub-regions. It seems that the accuracy of the simulation for such a limited area could be higher due to the fact that the results of the calculations would not be affected by data from the areas not affected by changes, and yet somehow influencing and "disturbing" results for areas with high variability.

Some minor coments are listed below:

Figure 1: Due to the fact that Land is a journal aimed at international readers, location of the study area should additionally include a map of Xinxing County location against the background of all China.

Line 179: There is no publication assigned to position 48 in list of references.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript “Multi-scenario Simulation of Land use Change and Delineation of Urban Growth Boundaries Based on Multi-source Big Data: A Case Study of Xinxing County, Guangdong Province?” addresses a topic of great current interest. The article is clearly structured, the influencing factors are comprehensively considered, and the research methodology is informative. The following comments and suggestions are made to the authors for improving their work:

1. This title. what is big data? in my opinion, the big data should be removed.

2. The abstract should be reworked to make it clearer for the readers the research objectives, the type of analysis that has been done and the findings attained. Too long. Specifically, the abstract should be a total of about 200 words. It should be a single paragraph and should follow the style of structured abstracts, but without headings: 1) Background: Place the question addressed in a broad context and highlight the purpose of the study; 2) Methods: Describe briefly the main methods applied. 3) Results: Summarize main findings; and 4) Conclusion: Indicate the main conclusions.

3. Enhancing the logic between paragraphs in section “1 Introduction” will be helpful. Too long also. Try to focus on the most important information.

4. Xinxing county is mentioned in Section “Study area” as the main ceramic producing area. I am questioned in why choose a ceramic producing area as the research area for food safety and ecological security, and whether it is meaningful. Based on the existing description, this area may not sufficient as typical study area.

5. Figure 3 could be made clearer, especially for section of UGBs delineation. Too simple, not informative.

6. In line 292 “By adopting the LEAS module” was mentioned first without any explanation.

7. LULC change and land expansion are relevant but different concepts, Authors are needed to use them in an accurate and logical manner. For examples, section “4.2 Land use expansion analysis” emphasize LULC change more than land expansion and should be renamed, corresponding to the title of the manuscript, section 4.1 and 4.3.

8. The authors need to explain convincingly why only industrial and urban land was considered in section “4.3 Analyzing the underlying driving forces of the LULC”.

9. Figure 7 should be renamed and the horizontal axis should be clarified.

10. The section 5.1 should be clearly highlighting what is “Three-line Coordination” and how to get the results of “Three-line Coordination”. In case of a conflict between the farmland protection line and the ecological red line, which one shall prevail? The important thing is to make clear to the reader, so that one should avoid at all costs ambiguous and imprecise phrases. Furthermore, readers are not required to understand Chinese planning.

11. In line 471 and following it says: “Hence, we can conclude that the introduction of the multi-source big data can better explore the influence of human socio-economic activities in the LULC dynamics.”. I don't see any evidence to support this claim elsewhere in the manuscript. If using the big data is important, the authors should mention it more often.

12. All the figures are unclear. The authors should enhance the resolution. The caption of figure 2 is not clear. Spatial driving factors of what? Please check all captions of Figures and Tables.

13. Line 186, change “date” to “data”. Please carefully check the full manuscript.

14. The method of UGBs delineation is missing. Figure 3 contains three parts, but in the following methods, only 3.1 and 3.2, where is 3.3?

15. Change “4. Results and analysis” to “4. Results”.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

I have no further comments on this article. I would like to thank the authors for extensive and precise answers.

Best regards.

Reviewer 2 Report

Thank you for the revision. All my concerns are treated carefully. I think it can be accepted in its present form.