The Association between Carbon Emission and Urban Spatial Form—A Study of Zhuhai, China

Round 1

Reviewer 1 Report (Previous Reviewer 5)

The content of the manuscript was definitely improved.

Nevertheless, new added texts need to be revised.

For instance, the authors used several times the first-person pronoun “we”: this is not a good practice in writing scientific papers.

Furthermore, in lines 143-147, as the research described was concluded, the text should be written in past tense instead of present.

Sentence starting at line 146 is incomplete, as the verb “analyze” has no subject.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report (Previous Reviewer 1)

Comments have been addressed. 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Overall, this paper provides a good and attractive topic by exploring the relationship between carbon emissions and spatial form, where the spatial form was subdivided into landscape and social. Overall, the analysis is good, but the introduction is not logical, some information of the method section is missing, and the implication section is not provided. Please revise this paper substantially.

The abstract can be improved by adding some theoretical or general findings, rather than highly dependent on the Zhuhai case. Moreover, the first point of the conclusion does not necessarily indicate the carbon information. Please revise.

Line 52-54, it is too broad to describe the studies on the carbon emissions. Please directly go to the urbanization-related carbon emissions, so that authors can analyze the relationship between carbon emission and urban structures, and further the relationship between carbon emissions with social information. There have been many studies working on this. Please refer:

Wei, G., Bi, M., Liu, X., Zhang, Z., & He, B. J. (2023). Investigating the impact of multi-dimensional urbanization and FDI on carbon emissions in the belt and road initiative region: Direct and spillover effects. Journal of Cleaner Production, 384, 135608.

Zhou, Y., Yu, Y., Wang, Y., He, B., & Yang, L. (2023). Mode substitution and carbon emission impacts of electric bike sharing systems. Sustainable Cities and Society, 89, 104312.

Line 57-60, please remove such information, since such description does not focus on the urban carbon emissions, while they are associated with urban morphology. Please focus on the association between urban morphology and carbon emissions.

Line 66-77, not logical at all, please restructure. The information in line 57-77 can be shortened to no more than two sentences to describe the carbon sources and influential factors.

Line 81-82, move forward.

Line 106, it is not “whether”, you may investigate “how”.

Figure 1, it should not be the technology roadmap, you may mean framework for analyzing ……

Please also redraw Figure 1, some information is not readable. Moreover, LUCC, land use/cover change? Please use full name.

Line 114, why Zhuhai? What is the urgency?

Figure 2, please indicate the national map, province map and then the city.

Line 153, please briefly introduce the reason for such 15 indicators. The similar question for line 162. Please justify. How about the importance in urban planning, urban management or….?

Line 176, Edirect? Or subscript? See line 185 as well.

Authors failed to provide a section of discussion and implications. It is critical to provide this.

Reviewer 2 Report

This study tests the relationship between the land spatial index from Fragstat and carbon emissions and presents a low-carbon urban space strategy based on this. It is interesting approach and the manuscript is written well. However, I question the value of this study for mainly two reasons.

First, it is questionable whether the city-scale analysis in this study is relevant. As the author mentioned, these studies are usually conducted at the national level or as intra-city comparisons. But, this study set each district in a single city as the analytic unit. Land spatial index, socioeconomic factors, and carbon emissions of each district are not independent and have spatial autocorrelation to each other. Therefore, simple regression has limitations in statistical relevance. Moreover, the representativeness of the pattern derived from this study is limited to only the studied city. In my knowledge, more replicates (i.e., cities) are necessary to be able to suggest the low-carbon urban spatial strategy.

Second, non-Chinese readers who are not familiar with the background of Zhuhai city feel difficulty in following the manuscript. In the result section, geospatial patterns between districts in Zhuhai are described (e.g., “the scale of urban clusters in Xiangzhou is relatively small” [L. 282]). I failed to follow the descriptions with my low understanding of Zhuhai city and Chinese place names.

Reviewer 3 Report

The relationship between global climate change and greenhouse gas emission has been found and approved. Net zero carbon has been received increasing attention. Like authors mentioned, cities are responsible for such serious carbon emission. This study applies 50 clusters in Zhuhai to quantifying the spatial form and carbon emission. The followings are the questions for the authors.

1. Figure 1. There are no description regarding “city basic database”, “direct measurement method”, and “indirect measurement method” in section 1. It would be great to add up more discussion on past studies applying direct measurement and indirect measurement method to similar topics. 

2.Section 1. It would be great to add up research gap in section 1. For example, there are many discussions in mitigating carbon emissions in sectors, or cities. What is the main contribution from the article can fulfill the research gap?

3.Section 1. What are the definitions for all the indicators mentioned in Figure 1.

4. Section 2.2.1. The study applies landscape index to evaluating the urban form, and there are many parameters used. Is it necessary to use that many variables?

5. There are approaches measuring carbon emission. What are the benefits and limitations of applying such method in this study?

6. Due to the article attempt to explore the relationship between urban form and carbon emission, what is the method applied to do such discussions?

Reviewer 4 Report

Dear Authors,

This Paper expresses one of the main challenges for the next future,through an innovative scientific approach.

To appreciate some details

-The direct and indirect carbon emissions are both based on a multiplicative model.

-Normalisation formula needs to be explicited.

-Spearman rank correlation is a first  adequate approach to solve the multicolinearity problem.

-VIF Factor implements the Spearman methodology.

-In general,the methodology to exclude the most correlated variables is well adequate.Being applied on the space context,it gives a correct picture of the data distribution.

-If multicolinearity is detected and solutioned,it is worth to ask if heteroschedasticity could be present in nthis complex set of interrelated data.

The merit of this work is to propose a time-spatial approachand to give an impulse towards the necessary actions and decisions,to respect the Agenda 2030 on the reduction of carbon emissions.The territorial distribution of the emissions,combined with a time series analysis,is definitely innovative.The social consequances of carbon emissions constitues the fundament of the adaptation of the territory management to its population.

Reviewer 5 Report

The paper aims to study the Association between Carbon Emission and Urban Spatial Form.

The proposed methodology seems to be a way to meet this purpose but only as a generalized estimation. Using planning and governance units that can have in their area characteristics not homogeneous, may give estimation that are not always the best representation of the reality.

On the other hand, some recommendations given by the authors are too firm, almost as an imposition. It is advised to rephrase those sentences.

Line 83: sentence as no main verb. English review is needed

Line 88: Which other reasons?

Line 96: sentence is too long. Review

Line 118: “socialist modern international special economic zone” what kind of zone is that? Furthermore, 5 adjectives in a row are used to classify the zone. English Review is needed.

Line 150: All tables should be kept in one peace, in the same page. Table 1 is split.

Line 161: Table 2 is split

Line 179: “-2.3” should be together on the same line

Line 222: Table 3 is split

Line 234: Table 4 is split

Line 236: “…this paper eliminated the 236 landscape spatial form index…” the paper eliminated? If think that was the authors. Review

Line 335: You are calculating the carbon emissions or an estimation?

Line 381: Table 7 is split

Lines 417-420: Those recommendations are quite peculiar and last sentence is incomplete. Review.

Line 449: Title is at the bottom of the page

Some references seem to be incomplete, using “et al.” instead of all authors names.