Study of Human Activity Intensity from 2015 to 2020 Based on Remote Sensing in Anhui Province, China
Round 1
Reviewer 1 Report
"Study of Human Activity Intensity from 2015 to 2020 Based on Remote Sensing in Anhui Province, China" is a well-written article. It is about an interesting topic that involves some physical features as well as human activities in relation to a very relevant feature of territory dynamics: the land cover variation.
Regarding the aims and scope of the Journal, the manuscript seems to be adequate for the following topic: Ecology and the Environment.
In my opinion, the manuscript could be published after some modifications which are described, as follows:
1) Study area: Figure 1. I suggest changing the colors for the topography. The blue color is more adequate to represent water coverage. I suggest adding the source of the information for the cartography elaboration ate the epigraph (as an example: administrative boundaries, vectorial information)
2) Methods: in this section authors describe the sources of the data. I suggest adding the temporal resolution of them. It is annual? Have the authors selected only two years (2015 and 2020) from a longer series of data?
What are the criteria for the selection of those years? I suggest explaining and justifying this part of the methodology.
3) Figure 2 shows the percentage of the variation of HAILS. I suggest indicating this feature in the epigraph.
4) Figure 4. Which characteristics of the river could be the reason or driving force for the variation of HAILS along flow path distance? I suggest adding information about this.
5) Results: The Ecological protection policies were pointed out as driving forces for the HAILS. However, they were not described or detailed in the manuscript. I suggest adding information about this analysis.
6) Results: from the equation of HAILS index, I understood that there are available data regarding types of land covers. I suggest adding this information in a figure or in a table.
What is the most representative land cover (area extension) in the study area?
7) Typing errors: page 1, line 41, typing error: "seclecting"
page 2, lines 80-81, please verify the redaction
Author Response
We have carefully considered and accepted all your suggestions. The main corrections to the paper and the responses to the comments are detailed in "author-coverletter-27488517.v1.docx".
Author Response File: 
Author Response.docx
Reviewer 2 Report
First of all, I would like to congratulate the authors for the effort made. Secondly, I believe that the selected topic may be of interest for possible publication if the indicated changes are made. The authors analyze the relationship between human activities and land cover and the territorial implications of this in the Anhui area (China). The work does not generate great international interest, as it is a case study and the designed methodology does not incorporate novel elements. However, for a sector like the one analyzed, it seems to me that this type of work is of great interest and usefulness. Although it is not the subject of this work, what is interesting about the analysis carried out is that it constitutes an element of great value for designing future simulations of land use change in the analyzed region, for example from models based on cellular automata. In addition, this fact can also be linked to sustainability actions, aimed at GHG reduction strategies or the design of urban adaptation actions against climate change. However, I believe that before its possible acceptance, the authors must make a series of improvements to make the work more interesting internationally.
a-) Introduction: The authors should improve it so that this section is of greater interest. Almost all of the references provided refer to China. As it is an international journal, I believe that the introduction should introduce papers that address the issue of work in other sectors (Europe, the United States, etc.). In this way it will be of more interest to readers.
b-) Materials and Methods: The designed method satisfies the objective of the work. However, I only suggest improving the resolution of figure 1. Similarly, the red letters of the municipal districts are difficult to read.
c-) Results: I recommend increasing the size of figure 2. On figure 3 the axes can hardly be read. In general, all the figures (3,4,5,6,7 y 8) in the manuscript have to be improved, as far as their resolution and size are concerned.
d-) Discussion: As in the introduction, I suggest including works from regions other than China. It is important to compare whether the results commented by the authors are also found in other spaces. For all these reasons, the originality of the work may be reduced if comparisons are not made. It would also be interesting if in the discussion the authors comment in detail on how the work being presented can contribute to carrying out new, more complex investigations. For this, it is important to review the literature again.
e-) Conclusions: They are well proposed, however it would be interesting if the authors could expand this section.
f-) References: This is the main weakness of the article, it is necessary to incorporate a greater number of references to work carried out in other sectors. This will enhance both the introduction, the discussion and the conclusions.
Author Response
We have carefully considered and accepted all your suggestions. The main corrections to the paper and the responses to the comments are detailed in "author-coverletter-27603823.v1.docx".
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript aims to estimate the intensity of human activities on land surface (HAILS) in Anhui Province, China, by analyzing land use and cover data from 2015 and 2020. The manuscript examines the spatial, slope, and hydrological distribution characteristics of HAILS and identifies the drivers of HAILS changes. However, the manuscript has several issues that require attention.
1. The manuscript's innovation point is weak, as there have been numerous studies characterizing the intensity of human activities on land surfaces. The study merely applies similar methodologies to a new study area, namely Anhui Province.
2. The manuscript does not sufficiently highlight the "interaction" between human activities and land cover, which is essential to understanding the intensity of HAILS.
3. The introduction section of the manuscript lacks an explicit statement of motivation for the study, which could clarify the study's objectives and research questions.
4. The literature review section of the introduction appears to be merely a compilation of existing research without offering a comprehensive synthesis or critical evaluation of the literature on the research topic.
5. The manuscript does not clearly explain why HAILS was chosen to characterize human activity intensity.
6. Subsections 2.3.2 do not present the analytical methods used in the manuscript clearly.
7. The manuscript's choice of using population density, average land GDP, and average nighttime light data to validate the HAILS index is unclear. It is not evident why these variables were chosen instead of directly modeling human activity intensity.
8. The discussion part of the manuscript lacks a comprehensive analysis of the essential reasons behind the study's findings.
9. The manuscript did not analyze specific change areas and actual values at the spatial level when exploring the driving factors that led to the changes in HAILS.
Author Response
We have carefully considered and accepted all your suggestions. The main corrections to the paper and the responses to the comments are detailed in "author-coverletter-27603823.v1.docx".
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The authors have satisfactorily answered all my first-version questions.
Author Response
Thank you very much for your previous suggestions. We have accepted all the suggestions and have expanded the manuscript again.
Author Response File: Author Response.docx
Reviewer 2 Report
Dear authors,
Thank you for responding to all my suggestions. Congratulations for the work done.
Author Response
Thank you very much for your previous suggestions. We have accepted all the suggestions and have expanded the manuscript again.
Author Response File: Author Response.docx
Reviewer 3 Report
The authors have addressed the comments raised by the reviewers. I have no further question.
Author Response
Thank you very much for your previous suggestions. We have accepted all the suggestions and have expanded the manuscript again.
Author Response File: Author Response.docx
