Exploring Public Preference and Willingness to Pay for the Ecosystem Benefits of Urban Green Infrastructure: Evidence from a Discrete Choice Experiment of Pilot Sponge Cities in China

Round 1

Reviewer 1 Report

Dear Authors,

Your research has demonstrated exceptional quality and has made significant contributions to the field of urban green infrastructure and ecosystem services evaluation. The topic of urban green infrastructure and its role in ecosystem services is of utmost importance in the context of sustainable urban development. Your manuscript addresses a relevant and timely subject, shedding light on the public's perception and willingness to invest in such projects, particularly in pilot Sponge Cities in China. Your study design is well-structured, and the data analysis is thorough, enhancing the credibility of your research outcomes. The implications and recommendations derived from your study have significant practical value for policymakers and urban planners therfore recommend the publication of your manuscript.

 

However it would be beneficial if the authors could incorporate more global examples and studies related to the topic. While the regional examples presented in the paper are essential for context and understanding, a broader perspective that includes findings from various regions and countries could enrich the study's analysis and strengthen its conclusions. By including international research, the manuscript can highlight common trends, variations, and challenges that might exist across different geographical contexts. This broader outlook would not only make the study more relevant to a wider audience but also increase its potential to be cited and referenced by researchers worldwide.

Author Response

Dear Reviewer,

We appreciate this encouraging comment.

According to your advice, we have added some global examples and studies related to the topic in introduction section (page 2, line 65-73).

At the same time, we believed that global studies mentioned in the discussion section can also be used to strengthen conclusions and highlight common trends, variations, and challenges that might exist across different geographical contexts.

Reviewer 2 Report

added in the pdf file attached

Comments for author File: Comments.pdf

Minor corrections needed.

Author Response

Dear Reviewer,

Thanks for the valuable comments.

We have revised the manuscript accordingly. 

1. Line 49-50: please correct the sentence.

We have corrected the sentence. See page 2, line 48-51.

2. Line 77: Elaborate WTP here.

We have revised the sentence to specify the WTP here. See page 2, line 84.

3. Line 78: Put space.

We have put space. See page 2, line 85-86.

4. Line 134: Remove the blank spaces.

We have removed.

5. Line 152: The opinions on ecosystem services may also be taken and explained in introduction section.

In introduction section, we have described how GI can provide ecosystem services in page 2, line 56-58.

6. Line 176: Explain this section properly.

We have explained this section as properly as possible.

7. Line 273: Where are the results for such a scientific term? Need to be added.

We have added the description of it in results section in page 8, line 255-256 and line 263-264.

8. Line 286-287: How ecosystem services were enumerated and used in this article is not clear, that needs to be clarifier.

We added information about ecosystem services in 2.2.3. Questionnaire design section (see page 5, line 180-184), and examples of cultural services are also added in parentheses (see page 11, line 320-321).

9. Line 359: May be improved with the addition of result oriented conclusions.

We agree that the addition of result-oriented conclusions is needed. We added more texts in the conclusions section (page 13, line 398-405) to improve our conclusions.

10. Line 384: Change font.

It has been changed in the page 13, line 427.

11. Line 389: Use times new roman fort for all the references.

We have changed them to “Times New Roman fort” and reorganized the literature.

Reviewer 3 Report

1.      Line 150: It is necessary to explain more detail why authors defined five attributes and their corresponding levels of ecosystem benefits, including reduction of run-off pollutant, degrees of ponding, plant type, planting aesthetics and their cost. Please describe the important reasons to choose these five attributes.

2.      Line 169: What much is the population in study area? How to sampling the respondents? The questionnaire survey was conducted on April 16 and 17, 2023. What is the effect of different month or season on the questionnaire survey?

3.      Line 176: 2.3. Econometric model. The different method of designed payment could affect research results. Please detail to describe your method of designed payment. In addition, did you have pre-tested your questionnaire design?

4.      Line 212: A total of 287 respondents completed the survey, including 267 valid questionnaires. These 267 respondents are too little. Maybe that could not reflect most residents’ opinions.

5.      Line 244: It is an important finding that male residents in Xianyang were more willing to pay for the improvement of GI’s ecosystem services, while older residents in Xianyang had lower WTP. Why? Are there similar literatures to support this finding?

6.      Line 270: In Table 8, the marginal WTP of residents is low for both Xianyang and Xi’xian New Area. Why is local residents’ marginal WTP for ecosystem services so low?

7.   Line 323: This may be because the government had failed to propagate the benefits of planting aesthetics brought by GI in Xianyang. How to change this situation?

Author Response

Dear Reviewer,

Thank you for your advice. We have revised the manuscript accordingly. 

1. Line 150: It is necessary to explain more detail why authors defined five attributes and their corresponding levels of ecosystem benefits, including reduction of run-off pollutant, degrees of ponding, plant type, planting aesthetics and their cost. Please describe the important reasons to choose these five attributes.

More explanation regarding the defined five attributes and their corresponding levels of ecosystem benefits has been added in the page 4, line 133-143.

2. Line 169: What much is the population in study area? How to sampling the respondents? The questionnaire survey was conducted on April 16 and 17, 2023. What is the effect of different month or season on the questionnaire survey?

We have added the population of study area and method of sampling in the page 6, line 191-196 and line 203-205. Regarding the effect of different month or season on the questionnaire survey, it may be a limitation of the study. We tried to add some reasons in page 6, line 197-201.

3. Line 176: 2.3. Econometric model. The different method of designed payment could affect research results. Please detail to describe your method of designed payment. In addition, did you have pre-tested your questionnaire design?

The designed payment method was described in page 4, line 147-152. Namely, based on the data of Water Resources Bulletin of Shaanxi province in 2021, the average annual personal water fee was calculated. In Xianyang, it was 649.98 yuan/year, and in Xi’xian New Area, it was 706.56 yuan/year. Therefore, we set 0%, 5%, 10%, 15%, 20% and 25% of the average annual personal water fee in the two regions as the levels of the cost attribute (Table 1).

 

We have pre-tested our questionnaire design and we have added the explanation for conducting the questionnaire pre-test in the page 5, line 186-187.

4. Line 212: A total of 287 respondents completed the survey, including 267 valid questionnaires. These 267 respondents are too little. Maybe that could not reflect most residents’ opinions.

We added the sample size determination method in the page 6, line 191-196. Based on the Scheaffer equation, the effective sample size of Xianyang should be 150, and that of Xi’xian New Area should be 100. Meanwhile, after data cleaning, a total of 2403 valid choice observations were retained for further analysis. Thus, it is reasonable to believe that the data collected is representative.

5. Line 244: It is an important finding that male residents in Xianyang were more willing to pay for the improvement of GI’s ecosystem services, while older residents in Xianyang had lower WTP. Why? Are there similar literatures to support this finding?

We analyzed factors related to gender in section 4.2.2 (page 13, line 380-393). The results above were similar to many previous studies as explained in the section.

6. Line 270: In Table 8, the marginal WTP of residents is low for both Xianyang and Xi’xian New Area. Why is local residents’ marginal WTP for ecosystem services so low?

It is an interesting question. Comparing with previous studies (page 2, line 67-73), residents’ marginal WTP of the two case studies were not lower.

However, it is worth thinking deeply regarding this phenomenon. Residents normally showed a willingness to pay for GI, but the amount of there are willing to contribute tends to relatively low. This highlights the need to explore additional solutions to address the funding challenges associated with the implementation of GI for stormwater management.

7. Line 323: This may be because the government had failed to propagate the benefits of planting aesthetics brought by GI in Xianyang. How to change this situation?

Some suggestions have been added in the Conclusion section (page 13, line 414-418). For example, government decision-makers should firstly popularize GI knowledge to residents before building GI in the community in order to obtain paid support from them. Moreover, the knowledge of rainwater utilization can also be incorporated into school education to raise cognition of the younger generations.