Regional Differences in Carbon Budgets and Inter-Regional Compensation Zoning: A Case Study of Chongqing, China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript assessed the annual carbon emissions, carbon sequestration, carbon deficit, and interregional carbon compensation costs from 2000 to 2021 in Chongqing, China. This study contains some interesting findings which revealed inequities in carbon compensation and proposes a novel zoning solution, which can provide scientific reference and data support for further establishing interregional carbon compensation mechanisms. I believe this article is of high quality and suitable for publication in the Land journal. However, there are some issues that need to be addressed. Therefore, minor revision is required before this manuscript can be accepted for publication in Land.

1. LINE 129 needs correction.

2. LINE 251 needs correction.

3. LINE 317 needs correction.

4. It is recommended to add a discussion on different zoning development strategies in the discussion section to enhance the practical value of the results.

5. Standard coal coefficients and carbon emission coefficients, these coefficients are based on previous studies. What are the criteria for selecting these references? Could this lead to uncertainty in the research results? I suggest discussing this in Section 4.4.

6. In addition to important findings, the conclusion section should also include the paper's innovative methods and suggestions for future research.

7. The references seem to be exclusively from Chinese scholars; I suggest appropriately including research from scholars in other countries.

Author Response

Brief summary: This manuscript assessed the annual carbon emissions, carbon sequestration, carbon deficit, and interregional carbon compensation costs from 2000 to 2021 in Chongqing, China. This study contains some interesting findings which revealed inequities in carbon compensation and proposes a novel zoning solution, which can provide scientific reference and data support for further establishing interregional carbon compensation mechanisms. I believe this article is of high quality and suitable for publication in the Land journal. However, there are some issues that need to be addressed. Therefore, minor revision is required before this manuscript can be accepted for publication in Land.

Response: Thank you very much. We are grateful for your professional comment; it is very helpful to improve the logic and content of this manuscript. After careful reading and consideration, we have made significant revisions, and the point-to-point responses are as follows:

 

Comments 1. LINE 129 needs correction.

Response: Thank you for your patient reminder, we agree with this comment. Following your guidance, we have corrected this and other similar errors arising from software failures, as detailed on page 4, lines 131-132 of the revised manuscript.

 

Comments 2. LINE 251 needs correction.

Response: Thank you for your patient reminder, we agree with this comment. Following your guidance, we have corrected this and other similar errors arising from software failures, as detailed on page 9, line 254 of the revised manuscript.

 

Comments 3. LINE 317 needs correction.

Response: Thank you for your patient reminder, we agree with this comment. Following your guidance, we have corrected this and other similar errors arising from software failures, as detailed on page 12, line 320 of the revised manuscript.

 

Comments 4. It is recommended to add a discussion on different zoning development strategies in the discussion section to enhance the practical value of the results.

Response: Agree, and thanks for your suggestion. Based on your meaningful comments, we have enriched the discussion on the different zoning development strategies in in Section 4.3. The results of carbon compensation zoning in this study are consistent with those of existing planning schemes and further quantify compensation costs, and can provide support for the implementation, management and dynamic adjustment of relevant planning in Chongqing. For example, extracting the corresponding amount of tax transfers from key payment areas and basic payment areas to key recipient areas and basic recipient areas, as well as encouraging cooperation in industrial transfer, environmental protection, eco-product development, etc. based on the complementarity between key payment areas and key recipient areas, which will be conducive to coordinating the promotion of China's carbon neutrality target (please refer to page 18, lines 477-485).

 

Comments 5. Standard coal coefficients and carbon emission coefficients, these coefficients are based on previous studies. What are the criteria for selecting these references? Could this lead to uncertainty in the research results? I suggest discussing this in Section 4.4.

Response: Agree, and thanks for your suggestion. We have added the criteria for setting these coefficients in Materials and Methods. These coefficients set according to previous studies, taking into account the information provided by the IPCC guidelines for national greenhouse gas inventories, China Energy Statistical Yearbook and the practical situation in Chongqing (please refer to page 4, lines 132-134). In addition, we also agree that these parameters may lead to uncertainty, as this is a common problem in carbon budget estimation. Following your comment, we have added more discussion of them in Section 4.4 (please refer to page 18, lines 487-496).

 

Comments 6. In addition to important findings, the conclusion section should also include the paper's innovative methods and suggestions for future research.

Response: Thank you for pointing this out, we agree with this comment. As you suggested, we have, we have enriched the Conclusion and covered this paper's innovative methods and suggestions for future research (please refer to pages 18-19, lines 498-525).

 

Comments 7. The references seem to be exclusively from Chinese scholars; I suggest appropriately including research from scholars in other countries.

Response: Many thanks for your suggestion. As you suggested, we have added more references, including 8 papers from scholars outside China (please refer to pages 22-23, lines 663-721). It should be explained that due to China's additional attention and exploration of interregional carbon compensation, the references in this paper are mainly from Chinese scholars.

 

Thank you for your insightful and thoughtful comments.

Reviewer 2 Report

Comments and Suggestions for Authors

After reading this article, I have a few suggestions for improving it:

 

- the quotations in abstract are unacceptable

 

-The abstract mentions the use of "optimisation methods" to estimate carbon emissions, sequestration and the deficit, but does not specify which methods were used or how they were applied. A brief mention of the specific techniques or models used would increase the clarity and credibility of the study.

 

-The proposed carbon compensation zoning scheme is an important contribution of the study, but the criteria or rationale for the zoning categories (key payment areas, base payment areas, etc.) are not explained. A brief explanation of the factors considered in the zoning categorisation would make the abstract more comprehensive and informative.

 

-Can you explain the specific research gap that your study addresses in the existing literature on carbon offset zoning? It would be beneficial if you could clearly explain how your approach differs from or improves on previous methods.

 

-Your results suggest significant regional differences in carbon budgets within Chongqing. Can you provide more context or hypotheses on the driving factors behind these differences?

 

-How does the trend analysis account for possible future changes in carbon policy or economic development that could alter the carbon budgets of different regions?

 

-Have you conducted sensitivity or uncertainty analyses to assess how variations in input data or modelling assumptions might affect your results? This could strengthen the robustness of your results.

 

-The study mentions potential policy implications of your results. Could you elaborate more how your zoning recommendations could be implemented in practise, taking into account potential socio-political challenges?

 

- How does carbon offset zoning in Chongqing compare to other regions in China or around the world? A comparative analysis could provide more context for your findings.

 

-conclusion has to be extended with future recommendations

 

Author Response

Comment 1: the quotations in abstract are unacceptable.

Response: Many thanks for your suggestion, we agree with this comment. The Abstract has been reorganized, and we have changed the presentation of the research background to avoid the appearance of quotations (please refer to page 1, lines 15-17).

 

Comment 2: The abstract mentions the use of "optimisation methods" to estimate carbon emissions, sequestration and the deficit, but does not specify which methods were used or how they were applied. A brief mention of the specific techniques or models used would increase the clarity and credibility of the study.

Response: Many thanks for your suggestion, we agree with this comment. Due to the multiple techniques and models involved and limited abstract words, so we highlighted the local optimization in the estimation process, and the highlight of the carbon compensation zoning scheme is that it took into account the present situation and trend analysis (please refer to page 1, lines 18-21).

 

Comment 3: The proposed carbon compensation zoning scheme is an important contribution of the study, but the criteria or rationale for the zoning categories (key payment areas, base payment areas, etc.) are not explained. A brief explanation of the factors considered in the zoning categorisation would make the abstract more comprehensive and informative.

Response: Thank you for pointing this out, we agree with this comment. As you suggested, we have added the explanation for the zoning categories. All the counties were zoned into key payment areas, basic payment areas, key recipient areas and basic recipient areas; The key payment areas, which accounts for 39.47%, maintain and grow payment status and are the main sources of carbon compensation costs, while the key recipient areas, which accounts for 44.74%, maintained a negative compensation status and a continuous downward trend, meaning that they may receive increasing carbon compensation costs (please refer to page 1, lines 26-30).

 

Comment 4: Can you explain the specific research gap that your study addresses in the existing literature on carbon offset zoning? It would be beneficial if you could clearly explain how your approach differs from or improves on previous methods.

Response: Thank you for your professional reminder, we agree with this comment and have added a corresponding discussion in Section 4.3. At present, there are only a few studies conducted on the carbon compensation zoning scheme generally consider only the economic costs at the provincial or city level and lack detailed consideration of the changing trend. To address these deficiencies, we constructed a zoning scheme based on the present situation and trend analysis of county-level carbon compensation costs (please refer to pages 17-18, lines 456-465).

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Comment 5: Your results suggest significant regional differences in carbon budgets within Chongqing. Can you provide more context or hypotheses on the driving factors behind these differences?

Response: Agree, and thank you for your professional comment. We have carefully considered your suggestion and have provided more context on these regional differences. In terms of direct causes, regional differences in carbon budgets are due to the different spatial distribution of carbon emissions and carbon sequestration. Within Chongqing Municipality, the vast southeast and northeast regions provided more carbon sequestration than other areas, the preferentially developed urban and sur-rounding regions produced carbon emissions exceeding twice the sequestration (please refer to pages 16-17, lines 426-431). As for the differences in spatial distribution of carbon emissions and carbon sequestration and their driving factors, we intend to further explore and enrich them in future studies (please refer to page 18, lines 493-494).

 

Comment 6: How does the trend analysis account for possible future changes in carbon policy or economic development that could alter the carbon budgets of different regions?

Response: Thank you for your professional reminder. We have enriched the discussion of trend analysis for carbon policy and economic development. We believe that changing trends in carbon compensation costs implies the efforts of counties in carbon management, and only when their contributions are comprehensively considered can the incentive role of the compensation mechanism be better played, which is conducive to reducing the pressure of low-carbon transition in high-carbon emission counties, and avoiding those high-carbon absorption counties (which are usually low-income counties) from falling into a new " resource curse "  (please refer to page 17, lines 458-463).

 

Comment 7: Have you conducted sensitivity or uncertainty analyses to assess how variations in input data or modelling assumptions might affect your results? This could strengthen the robustness of your results.

Response: Agree, and thank you for your professional comment. Structural and parametric uncertainties are prevalent in carbon budget estimation models. In this study, some empirical parameters are used in carbon emission and carbon compensation costs accounting, and there is a certain dependence on population, NPP and other data. However, limited to the focus and length of this paper, we only local optimized the relevant parameters and data selection, and the corresponding sensitivity analysis and uncertainty analysis need to be enriched in the future (please refer to page 18, lines 486-196).

 

Comment 8: The study mentions potential policy implications of your results. Could you elaborate more how your zoning recommendations could be implemented in practise, taking into account potential socio-political challenges?

Response: Agree, and thank you for your professional comment. We have added more detailed recommendations in the Discussion for readers to understand and practice. The results of carbon compensation zoning can provide support for the implementation, management and dynamic adjustment of relevant policies in Chongqing. For example, extracting the corresponding amount of tax transfers from key payment areas and basic payment areas to key recipient areas and basic recipient areas, as well as encouraging cooperation in industrial transfer, environmental protection, eco-product development, etc. based on the complementarity between key payment areas and key recipient areas (please refer to page 18, lines 477-485).

 

Comment 9: How does carbon offset zoning in Chongqing compare to other regions in China or around the world? A comparative analysis could provide more context for your findings.

Response: Thank you for your professional reminder, we agree with this comment and have added more comparative analysis of the background of carbon compensation zoning. Similar to other urbanized regions, Chongqing’s total carbon emission is greater than its carbon sequestration, with an annual carbon deficit of 556.24×10⁴~3,621.58×10⁴ t; This means that carbon sequestration, mainly from terrestrial ecosystems, offsets about 40.37% of the anthropogenic carbon emissions, which is higher than the global average (33.69%) over the same period, and also high in China (please refer to page 16, lines 421-426). The reason for this phenomenon is that there were greater regional differences in the carbon budget within Chongqing, which provided the possibility and necessity for the exploration of carbon compensation zoning. In addition, direct comparative analysis can only be carried out when the framework proposed in this study is applied to the Chinese and world scales in the future.

 

Comment 10: conclusion has to be extended with future recommendations.

Response: Thank you for pointing this out, we agree with this comment. As you suggested, we have extended the Conclusion. The Conclusion was expanded into three paragraphs, which describe the important innovations, discoveries and significance of this study in turn (please refer to pages 18-19, lines 487-525), which we hope will meet your approval.

 

Thank you for your insightful and thoughtful comments.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper is well structured and very clear in its approach.

The characterization and calculation of the counties that present deficit or surplus in terms of emissions is interesting. 

However, from the point of view of the results, the lack of sensitivity of the calculation of emissions to the economic cycle is striking, which makes the calculation methodology unrealistic.  This is especially significant in the years most affected by the economic slowdown policies motivated by COVI-19.  In these years, no significant drop is observed.

From the point of view of CO2 absorption capacity, the results are also striking in relation to their clearly increasing trend. Some discussion of its limitations would be very useful because it is difficult to understand this trend. 

Finally, regarding the balance between emissions and absorption capacity, the results are interesting but would be more useful if they were clearer:

1. What is the value of the compensation for territories in terms of income of each county.

2. Who is the administration that draws the funds to establish the compensation between counties and where do these funds come from (local taxes, national taxes)?

3. It would be worthwhile to reflect on this calculation system and its capacity to achieve carbon neutralization at a regional scale, if it makes sense.

Author Response

Brief summary. The paper is well structured and very clear in its approach. The characterization and calculation of the counties that present deficit or surplus in terms of emissions is interesting. However, from the point of view of the results, the lack of sensitivity of the calculation of emissions to the economic cycle is striking, which makes the calculation methodology unrealistic.  This is especially significant in the years most affected by the economic slowdown policies motivated by COVI-19.  In these years, no significant drop is observed. From the point of view of CO2 absorption capacity, the results are also striking in relation to their clearly increasing trend. Some discussion of its limitations would be very useful because it is difficult to understand this trend. Finally, regarding the balance between emissions and absorption capacity, the results are interesting but would be more useful if they were clearer:

Response: We appreciate your professional and patient review. You understand our paper well, and your thoughtful and deliberate comments were very helpful for improving the quality of this paper. In particular, you mentioned the response of carbon emissions and carbon sequestration to the COVID-19 pandemic, which gives us a good inspiration. Chongqing's carbon emissions in 2019, 2020 and 2021 are 3892.17×10⁴ t C, 3849.87×10⁴ t C and 3688.6×10⁴ t C, respectively, showing a downward trend. During the same period, carbon sequestration are 1504.67×10⁴ t C, 1546.12×10⁴ t C and 1478.24×10⁴ t C, showing an fluctuating trend. The decrease in human activities during the COVID-19 pandemic may lead to a decrease in carbon emissions and fluctuations in carbon sequestration, but the content of this study is not enough to distinguish the specific impact of the Pandemic, which is worth further exploration. In addition, we added the limitations of the data and parameters used in the study (please refer to page 18, lines 486-496), and also added the content of carbon budget balance capacity (please refer to page 16, lines 421-425), and we expect the following responses to satisfy your concerns:

 

Comment 1. What is the value of the compensation for territories in terms of income of each county.

Response: Many thanks for your professional reminder, we have revised our analysis of the impact of carbon offsets on each region's GDP share (please refer to page 18, lines 486-496). For counties, the county that pays the highest costs is Yuzhong District, the costs accounts for 0.24-2.74% of GDP, while the county that should receive the most costs is Chengkou County, the costs accounts for 0.89-9.56% of GDP.

 

Comment 2. Who is the administration that draws the funds to establish the compensation between counties and where do these funds come from (local taxes, national taxes)?

Response: Thank you for your comment. The Chinese government pays close attention to the exploration of ecological compensation mechanisms, including carbon compensation, and has just issued a Regulation on Ecological Protection Compensation. For feasibility reasons, our proposed carbon compensation framework takes into account the provisions of this Regulation, that is, the sources of carbon compensation costs should not be limited, including both national and local taxes, and even the funding of social enterprises is appropriate. Accordingly, the forms of carbon compensation include financial transfer payment, counterpart cooperation, industrial transfer, purchase of ecological products and services, etc., and we also gave more detailed recommendations on the implementation of carbon compensation zoning scheme in section 4.3 (please refer to page 18, lines 477-485).

 

Comment 3. It would be worthwhile to reflect on this calculation system and its capacity to achieve carbon neutralization at a regional scale, if it makes sense.

Response: Thank you for your professional reminder, we agree with this comment and improve the corresponding Conclusions. A scientific and comprehensive zoning scheme can support the carbon compensation mechanism to better play an incentive role, guide regions to reduce carbon emissions or increase carbon sequestration, which is of great significance to the formation of a sustainable development model. In this study, a quantitative estimation and detailed analysis of the carbon budgets in Chongqing was completed, and a novel framework for interregional carbon compensation zoning was proposed. The research results can provide scientific solution for China's further exploration of local regional carbon compensation regulations and systems and promote China's carbon peak in 2030 and carbon neutrality in 2060 through local initiatives (please refer to pages 18-19, lines 498-525).

 

Thank you for your insightful and thoughtful comments.

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

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