Assessment of Urban Green Space Equity in Beijing’s Central Urban Villages: A Remote Sensing Perspective on Environmental Justice

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study takes into consideration an extremely important aspect concerning the salutogenic city, environmental justice, to evaluate the equitable distribution of green spaces in two different areas of the city of Beijing.

 

Very interesting topic, current, much studied, which has been treated by the authors with attention especially regarding the references to scientific literature.

The study is clearly organized, contains all components of a scientific article (introduction, materials and methods, results, discussions, and conclusions).

Overall, the article was interesting to read, and in my opinion the text is quite exhaustive and should only be integrated with some basic concepts on the salutogenic city.

Furthermore, I would clarify what the authors mean by quality of green spaces.

In my opinion, a more detailed literature review on environmental justice could be integrated into the introduction.

The aim of the study is clear, and the research questions are well outlined.

The results section was treated in a linear way by the authors, just as I find the sections relating to discussions and conclusions well argued.

Reading the article was, in my opinion, quite interesting and could interest readers, even from different areas, because the topic lends itself to being explored in a transversal way involving different disciplines. The topic is current, and, in my opinion, the article needs a minor revision before publication.

 

 

 

In particular

Introduction

The introduction to the study has been done with care, I would just go into a little more detail about the concept of environmental justice, in its different dimensions, connecting it to the salutogenic city.

 

Methods

The section was well organized and the subdivision into subsections makes the study very understandable. The description of the study area also seems quite detailed and clear to me.

The method was described clearly, but I do not find references regarding the evaluation of urban quality.

In lines 94-96 there is talk of a holistic approach in the evaluation that also incorporates vegetation quality and coverage. As for the measurement of vegetation cover, I find confirmation in the text and I understand the measurement method used, which has been described in quite a detailed manner.

But the evaluation of the quality of greenery? I do not find the reference to the holistic approach. Perhaps for the evaluation of quality it is necessary to clearly specify what is meant. That is, it would be appropriate to explain in the text what is meant by the quality of green areas.

Using a holistic approach in the evaluation, would I perhaps have used a more qualitative tool? But this essentially depends on the personal definition that I give to the "quality of green spaces". I believe it is useful to clarify this specific point.

 

Results

In general, the results are clearly described as detailed in the method section.

 

Discussions and conclusions

I appreciated how this section was treated. Well written and well researched.

Comments for author File: Comments.pdf

Author Response

Comments：But the evaluation of the quality of greenery? I do not find the reference to the holistic approach. Perhaps for the evaluation of quality it is necessary to clearly specify what is meant. That is, it would be appropriate to explain in the text what is meant by the quality of green areas.
Response： 
Thank you for pointing out. We agree with this comment. Therefore, we have add the explanation in "

2.3.4. Indicators of Green Space Quality". Thank you again for your patience and advice. I really appreciate and the chance to learn from you. 

Wish all the best to you.

Reviewer 2 Report

Comments and Suggestions for Authors

Since this paper was written carelessly, a strong rejection is recommended.

The paper has the following issues:

1. Professional abbreviations should be defined when first introduced. In this paper, NDVI appears multiple times without an initial definition.
2. Once an abbreviation is introduced, there is no need to repeatedly provide both the full term and the abbreviation. Otherwise, the purpose of using abbreviations is lost.
3. In line 212, "his study employs the Theil Index"—the use of "his" is inappropriate.
4. What does "2.1 Subsection" mean?
5. Is the sentence in line 129 incomplete?
6. The expression in lines 130-135 is inappropriate.
7. The formula (2) for NDVI is incorrect, which makes the entire FVC calculation completely wrong.
8. Lines 144-145 should be deleted.
9. The conclusion section is overly lengthy and needs to be more concise.
10. Many references are incorrect or missing.

Comments on the Quality of English Language

NO

Author Response

Comments 1： Professional abbreviations should be defined when first introduced. In this paper, NDVI appears multiple times without an initial definition.
Response： 
Thank you for pointing out. We agree with this comment. Therefore, we have add the explanation in Introduction.

Comments 2： Once an abbreviation is introduced, there is no need to repeatedly provide both the full term and the abbreviation. Otherwise, the purpose of using abbreviations is lost.
Response： 
Thank you for pointing out. I have correct all the mistake. It's my first paper, I finished the manuscript myself. I still have too much to learn. Sorry for my stupid mistake.

Comments 3： In line 212, "his study employs the Theil Index"—the use of "his" is inappropriate.
Response： 
Thank you for pointing that out. I was about to use "This" but "T" was missed. Thank you so much for your patience and sorry again for my careless. I have correct it in the new manuscript.

Comments 4： What does "2.1 Subsection" mean?
Response： 
Thank you for pointing that out. It should be "research framework". It's another mistake again.... It was right before submission. I still don't know what made it like this.... I'm so sorry for this.

Comments 5： Is the sentence in line 129 incomplete?

Response： 
Thank you for pointing out. It's in 133 now and it should be"

The research framework consists of three main components：

Green Space Data Extraction"

There is an enter being missed. Sorry again....

Comments 6： The expression in lines 130-135 is inappropriate.

Response： I have changed it to"

Urban green space information was extracted from Landsat remote sensing data using ENVI. The results are presented in Figure 1A (Section 2.2). Additionally, urban land use classification data was used to identify and delineate residential communities and urban villages, including their spatial extent and geographic distribution, as shown in Figure 1 (Section 2.2). The population of residential communities was estimated based on multiple factors, including building area, geographic location, building height, and the average residential floor area per capita in Beijing." Is there any problem? I'd like to correct any mistake. Thank you so much.

Comment 7： The formula (2) for NDVI is incorrect, which makes the entire FVC calculation completely wrong.

Response： 
Thank you for pointing that out. It was a mistake only in the manuscript. It didn't influence the calculation. We used ENVI for calculation, so it won't be wrong because of the formula.

Comments 8：Lines 144-145 should be deleted.

Response： 
Thank you for pointing that out. I have deleted the sentence in 144-145 "

The methods for calculating equity metrics are detailed in Section 2.3.3, and the results are discussed in Section 3.3."

Comments 9：The conclusion section is overly lengthy and needs to be more concise.

Response： 
Thank you for pointing out. I have shorten the conclusion section:

 

Investigating green space (GS) equity for disadvantaged groups is crucial for environmental justice. Urban villages (UVs) and residential quarters (RQs), two common residential types in Chinese cities, present stark contrasts in GS accessibility. Ensuring equitable GS access for UV residents aligns with the United Nations’ Sustainable Development Goals on reducing inequalities, yet research on this issue remains limited.

This study examines GS equity between UVs and RQs in central Beijing, considering varying buffer distances. Findings indicate that RQs have significantly more internal GS and better equity than UVs. However, intra-community disparities, rather than differences between UVs and RQs, are the primary drivers of GS inequity. Per capita GS inequity emerges as the dominant factor shaping overall GS disparities.

Based on these findings, targeted strategies are recommended to address GS inequities in central Beijing. This research also provides broader insights into GS equity in marginalized housing typologies, including informal settlements in developing regions. From an environmental justice perspective, it highlights the need for integrating GS improvements into urban renewal initiatives, with a focus on enhancing internal GS availability for disadvantaged communities.

Despite its contributions, this study has limitations. First, it focuses on residential GS inequities but does not consider GS access in other daily environments, such as workplaces or commercial areas, which may also impact well-being. Second, it does not differentiate between GS types, such as parks or community gardens, which offer distinct benefits. Future studies should adopt a weighted evaluation approach to account for these variations. Finally, the macro-level remote sensing assessment of GS quality does not capture micro-level attributes, such as recreational facilities, safety, and aesthetic appeal, which influence usage and perceptions. Future research should integrate these aspects for a more comprehensive understanding of GS equity.

It's more concise now.

Comments 10：Many references are incorrect or missing.
Response： 
Thank you for pointing out. We are trying to make the references better. Could you please tell us which part was missing and wich part was incorrect?

Thank you again for your patience and advice. I really appreciate and the chance to learn from you. 

Wish all the best to you.

 

Reviewer 3 Report

Comments and Suggestions for Authors

This study examines the equity of urban green space (GS) distribution between urban villages (UVs) and residential quarters (RQs) in Beijing's central urban areas, using remote sensing data and statistical equity measures. The findings reveal significant spatial disparities in GS accessibility and quality, emphasizing the role of intra-group inequities in shaping environmental justice outcomes.

Advantages:

1. Comprehensive Analytical Framework: The study integrates multiple dimensions of green space equity by considering per capita green space, Normalized Difference Vegetation Index (NDVI), and Fractional Vegetation Cover (FVC). This holistic approach provides a more nuanced understanding of GS distribution patterns.
2. Policy-Oriented Insights: The research highlights key policy implications for urban planning, identifying priority areas for improving GS accessibility and proposing strategies for integrating green infrastructure into urban development.

Areas for Improvement:

1. Lack of Remote Sensing Data Details: The study does not clearly specify the methodology for NDVI and FVC calculation, the spatial resolution of the remote sensing imagery, acquisition time, or preprocessing steps. These omissions impact the reproducibility of the results. It is recommended that the authors provide more details on the data sources (e.g., Landsat or Sentinel imagery) and the temporal range of analysis.
2. Limited Discussion on Causal Mechanisms: The study identifies disparities between UVs and RQs but does not deeply explore the underlying causes, such as land tenure, urban planning policies, and capital investment differences. Incorporating an urban political ecology perspective could help analyze how power structures influence green space distribution.
3. Vague Policy Recommendations: While the paper offers some policy suggestions, they remain broad and lack concrete implementation details. Future research should specify how particular policies could be designed and executed to enhance GS equity more effectively.
4. Lack of Ground-Truthing and Public Perception Data: The study primarily relies on remote sensing data and statistical models, lacking in-depth field surveys or qualitative insights. Future work could incorporate surveys, interviews, or social media analysis to capture public perceptions of green space equity and validate the remote sensing findings, refer to [1, 2]
   [1] Ruan, Tao, and Qin Lv. "Exploring equity perception of electric vehicles from a social media perspective." Transportation research interdisciplinary perspectives 25 (2024): 101103.
   [2] Ruan, Tao, and Qin Lv. "Public perception of electric vehicles on reddit over the past decade." Communications in Transportation Research 2 (2022): 100070.

Overall, this study provides valuable insights into urban green space equity but would benefit from more detailed methodological transparency, a deeper exploration of causal mechanisms, and a stronger integration of qualitative data.

Author Response

1. Lack of Remote Sensing Data Details: The study does not clearly specify the methodology for NDVI and FVC calculation, the spatial resolution of the remote sensing imagery, acquisition time, or preprocessing steps. These omissions impact the reproducibility of the results. It is recommended that the authors provide more details on the data sources (e.g., Landsat or Sentinel imagery) and the temporal range of analysis. 

Response:

Thank you for pointing that out. We have specified the methodology for NDVI and FVC calculation in the Method section. Please check the new manuscript. I appreciate your patience.

2. Limited Discussion on Causal Mechanisms: The study identifies disparities between UVs and RQs but does not deeply explore the underlying causes, such as land tenure, urban planning policies, and capital investment differences. Incorporating an urban political ecology perspective could help analyze how power structures influence green space distribution.

Response:

Thank you for your advice. We have deeply explored the land tenure, urban planning policies, and capital investment differences in dthe iscussion in the new manuscript. Thank you for your advice and patience. 

3.Vague Policy Recommendations: While the paper offers some policy suggestions, they remain broad and lack concrete implementation details. Future research should specify how particular policies could be designed and executed to enhance GS equity more effectively.
Response:

We have added more detailed Policy Recommendations in the discussion section. Thank you again for your patience.

4.Lack of Ground-Truthing and Public Perception Data: The study primarily relies on remote sensing data and statistical models, lacking in-depth field surveys or qualitative insights. Future work could incorporate surveys, interviews, or social media analysis to capture public perceptions of green space equity and validate the remote sensing findings, refer to [1, 2]

Response:

Thank you for your advice. We are planning to do more research based on Ground-Truthing and Public Perception Data and the paper you recommended has inspired us a lot. In our future research, we will learn more from the paper you recommended. Thank you so much.

Wish all the best to you.

 

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The author seems to be very careless.

The full terms for NDVI, FVC, etc. are introduced the first time they appear in the article, and abbreviations should be used thereafter. However, in the revised manuscript, there is still a frequent mix of full terms and abbreviations.

Many references are incomplete; many lack page numbers or article numbers, the format is inconsistent, and some references are duplicated.

Author Response

Comment 1:
The full terms for NDVI, FVC, etc. are introduced the first time they appear in the article, and abbreviations should be used thereafter. However, in the revised manuscript, there is still a frequent mix of full terms and abbreviations.

Response 1:
We sincerely appreciate this insightful observation. We have now carefully reviewed the entire manuscript to ensure that:

All abbreviations (e.g., NDVI for Normalized Difference Vegetation Index, FVC for Fractional Vegetation Cover) are consistently defined upon their first appearance in both the abstract and main text.

Comment 2:
Many references are incomplete; many lack page numbers or article numbers, the format is inconsistent, and some references are duplicated.

Response 2:
We deeply regret these oversights and have thoroughly addressed them by:

1. Completing all references: Added missing page numbers (e.g., Reference 22, 23), article numbers (e.g., Reference 35, 70), and DOIs where available.

2. Standardizing formatting.

3. Removing duplicates.

We are grateful for these constructive suggestions, which have significantly improved the manuscript's rigor and readability. Please let us know if any additional refinements would be helpful. Thank you so much for your patience. I really appreciate it.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

NO