Analysing the Driving Forces and Environmental Effects of Urban Expansion by Mapping the Speed and Acceleration of Built-Up Areas in China between 1978 and 2017

Round 1

Reviewer 1 Report

The manuscript entitled "Mining the Driving Forces and Environmental Effects of Urban Expansion by Mapping the Speed and Acceleration of Built-up Areas in China between 1978 and 2017" aimed to quantify the dynamics of urban expansion in China using information derived from remotely sensed satellite sensor data.

In my opinion, the manuscript is suitable for publication in Remote Sensing, after the authors have addressed the following comments below.

1) Page 1, lines 37-38: You mentioned, “Built-up areas concentrate population and economic activities and facilitate socioeconomic progress”. It is confusing. Population and economic activities are concentrated in built-up areas not the reverse. So, rewrite the senescence.

2) Page 2. Lines 48-57: The authors should report the previous studies that used nighttime satellite data to explore the dynamics of urban expansion at the national scale of China.

3) Page 2. Line 65: You have to write the full name of the WTO in the first time. After that, you can use the acronym. Also GAIA in line 89.

4) Page 2, line 85: Always use a term “spatial resolution”. Rewrite the sentence.

5) Page 2, line 87: Put a reference at the end of the sentence (… more than 90%).

6) Page 3, lines 125-135: You have to define a city and where it is located in relation to the administrative divisions of China. Is it smaller or larger than the township level? In addition, what is the smallest, largest and mean numbers of population for each class (small, medium, largest and mega cities). Provide a table.

7) Page 5, lines 163-164: This sentence is not clear “Theoretically, along with industrial transformation, the importance of land expansion for economic development diminishes”.

8) Page 6, line 207 (Figure 5): Maps in Figure 5 should be clear. It is recommended to be presented in a full page.

9) Page 7, line 218 (Figure 6): Figure 6 must be self-explained. What do the numbers (highlighted in red) mean i.e. 19,434, 60,046 and 94,994?

10) Page 7, lines 220-232: Give some results (numbers) of the size of the built-up areas.

11) Page 11, line 314 (Figure 10): I don’t think it is necessary to draw a line for the built-up area in Figure 10a (the black trend line). The title of the x-axis must be written (Years).

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear authors, the manuscript is well-conceived and informative but it has some inadequacies.  I shall highlight them and the authors might improve the quality and readability of this research paper accordingly.

1. All the geo-referenced maps and other details (Figures 2,5,6,7,10 and A1) should be included in high resolution so that the details and the legends in each figure could be read properly.
2. The most relevant data-results should be summarized and demonstrated by a graph and a corresponding table.
3. Please, highlight the outliers in your table/s.
4. The introduction section needs elaboration on the literature review to set the manuscript in an international context and show how it builds on previous work on the subject.
5. The methods are not correctly described and sufficiently informative to allow replication of the research. Make the workflow design more detailed. 
6. The models presented in the manuscript require sufficient details (including calibration, sensitivity analysis and validation) to allow other researchers to develop and test the models later on. Please include the parameters that I have mentioned here.
7. Please, briefly add future perspectives and further applied applications of this specific research work in the manuscript, before the conclusion section.
8. The English language of the paper needs a thorough revision. Please have the manuscript proofread by competent authorities and include the certificate on resubmission. 

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Manuscript: remotesensing-1005423

Title: Mining the Driving Forces and Environmental Effects of Urban Expansion by Mapping the Speed and Acceleration of Built-up Areas in China between 1978 and 2017

 

 

Overall: The manuscript is mostly well written, and the authors/researchers have done a good job in breaking the process into sections with a logical order. Despite that, there were some major editions needed in the manuscript, with some questions/concerns that need to be considered during the revision. Thus, all parts need improvement to provide a strong justification for the study.

In particular:

1. Please, do not use numbering within abstract.
2. Please, expand the abstract explaining a little more your methodology.
3. The introduction is very poor and focuses only on China. Reference should also be made to studies that have been carried out for urban expansion worldwide. You should provide more references about relevant studies and you should describe what new your work brings. I need more technical motivation for this project.
4. A minor point: in subsections 2.1 and 2.2 begin with Capital letter.
5. Please provide a table for the used data with all the appropriate information.
6. In 2.2 subsection, you are presenting the steps of your work and these steps are not clear in Figure 1. Please, remake figure 1 and provide with a better resolution.
7. Again, you should point the steps that you are describing in 2.2.1, in Figure 2.
8. Please remake Figure 2, and make the flow vertical. At this point all the information that you want to provide is disappearing.
9. P3L117: The formulae of speed and acceleration in step 4 are as follows…Correct the word formula
10. Please provide a better resolution image for Figure 3. And make it bigger.
11. In terms of heterogeneity, I would like to a spatial index like Moran’s I, in order to justify what you have done.
12. Figure 5 is very poor in order to justify your work. Please for speed and acceleration close to zero (0), please use a hollow symbol
13. Figure 6 is very impressive. Bravo. But please, use for the little diagram the same color palette as the bigger one, while make it bigger in order the letters to be readable.
14. In Figure 7, please maximize the symbols within the map and also the diagrams are not readable. Perhaps you should put them under the map while maximizing the map to cover the page width.
15. Again, in Figure 8 letters are not readable, while the aesthetic view of it, is great.
16. In Table 1 and 2, please maximize the size of the numbers.

Well done.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The manuscript has been improved. However, the authors did not addressed the second comment in the first version. Thus, after addressing this comment, I believe the work is ready for publication.

Page 2, lines 66-83: You have to talk about the pervious studies that used DMS-OLS data to to explore the dynamics of urban expansion at the national scale of China. For example, studies such as:

Spatiotemporally enhancing time-series DMSP/OLS nighttime light imagery for assessing large-scale urban dynamics

Extracting the dynamics of urban expansion in China using DMSP-OLS nighttime light data from 1992 to 2008

Urban Growth and Rural Transition in China Based on DMSP/OLS Nighttime Light Data

 

Author Response

We are sorry that we misunderstood your suggestion in the last version. Thank you for explaining it in such a detail. As you suggested, nighttime light data is essential. It is a kind of remote sensing data, which, to some extent, reflects the intensity of socio-economic and human activities. And it’s suitable for studies at large spatial scale due to its relative low resolution. The results of previous studies using DMSP-OLS data were summarized in line 66-80.

Thank you again for helping us improve this manuscript!

Reviewer 2 Report

Dear authors, I am okay with the changes made. Please, kindly double-check Figure 11(a). Thanks.

Author Response

Thank you for your suggestion. We have double-checked Figure 11(a) and rearranged the layout so that the text does not obscure the underlying lines. And the data source have also been checked. Characteristic of environmental data is described in Table 1, with missing data pointed out.

In all, we do appreciate your suggestions for improving this article. We really get a lot from it. Thank you!

Reviewer 3 Report

Thank you for accepting my comments.

Author Response

We appreciate the time and effort you spent on reviewing this article. Thank you for helping us improve this manuscript!