Does Urbanization Affect the Carbon-Output Efficiency of Agriculture? Empirical Evidence from the Yellow River Basin
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
Article entitled “Will urbanization affect the low-carbon efficiency of agriculture?-- Based on empirical evidence from the Yellow River Basin” concerns a very important and current research problem. The authors correctly justified the purposefulness of the research and used very advanced research methods.
The structure of the article is correct and the conclusions result from the research conducted.
The article is very professionally prepared and should be published. However, I have few minor suggestions:
1. In the introduction, the authors could refer not only to Chinese documents regarding the need to reduce carbon emissions, but also to many other important policies promoting a low-emission economy (SDGs, Fit for 55, etc.)
2. Please improve the quality of the Figure 2. The legend is unreadable.
3. Consider using colors on all maps (why are some maps in color and others in black and white?)
4. The recommendations are quite general. The research results allow for the formulation of more detailed recommendations.
5. There is a lack of discussion of the results. Please consider the possibility of comparing your results with those of other authors.
Author Response
AE1: In the introduction, the authors could refer not only to Chinese documents regarding the need to reduce carbon emissions, but also to many other important policies promoting a low-emission economy (SDGs, Fit for 55, etc.)
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. In the introduction, we add the SDGs and other policies to promote carbon reduction. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 33-Line 37)
The 17 Sustainable Development Goals (SDGs) are a unified global sustainable development evaluation system proposed at the United Nations Sustainable Devel-opment Summit in 2015. The goal of achieving a carbon peak by 2030 and carbon neu-trality by 2060, announced by China at the United Nations General Assembly in 2020, is one of the important components of the SDGs[1].
[1]Xi,J.X.;Construction and measurement of regional sustainable development evaluation system under the background of "dual carbon" and common prosperity.N. Zhejiang University,2023
AE2: Please improve the quality of the Figure 2. The legend is unreadable.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We replaced Figure 2 with a cleaner version. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 495-Line 496)
AE3: Consider using colors on all maps (why are some maps in color and others in black and white?)
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have replaced Figure 3 with a color version. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 503-Line 505)
AE4: The recommendations are quite general. The research results allow for the formulation of more detailed recommendations.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have made changes to the policy recommendations section to make them more specific. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 953-Line 964)
Therefore, regional cooperation and exchanges should be strengthened. Cities with high agricultural low-carbon efficiency should play a positive driving role, share successful experiences with neighboring cities with low efficiency, share advanced low-carbon agricultural technologies and scientific research results, and improve agricultural production efficiency. Cities with low agricultural carbon efficiency should take the initiative to learn from neighboring cities with high efficiency, combine their own environment and specific development conditions, improve agricultural production and management methods, enhance agricultural low-carbon efficiency, and narrow the gap between them and neighboring cities. Specifically, long-term comprehensive real-time monitoring can be carried out through the establishment of a carbon emission pollution linkage early warning mechanism in neighboring regions so as to strengthen exchanges and cooperation between regions to improve agricultural low-carbon efficiency[48].
[48] Li,L.;Xu,W.X.;Zheng,J.H. Spatial interaction between urbanization process and eco-efficiency in the Yellow River Basin.J. Economic Survey,2022,39,25-34.
AE5: There is a lack of discussion of the results. Please consider the possibility of comparing your results with those of other authors.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We supplement the discussion of the results in the conclusion section of the study. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 882-Line 922)
5.1. Discussion
Based on the panel data of 75 cities in the Yellow River Basin from 2000 to 2020, this paper used the super-DEA model for the first time to measure the low-carbon ef-ficiency of agriculture. Then, the theoretical logic of urbanization's impact on the low-carbon efficiency of agriculture is established. The three-dimensional kernel den-sity model and Markov chain model were used to measure the dynamic evolution and regional differences of agricultural low-carbon efficiency under spatiotemporal heter-ogeneity. The panel Tobit model analyzed the relationship between urbanization and low carbon efficiency in agriculture. In terms of agricultural low-carbon efficiency, this paper comprehensively considers the coordinated and overall development of resource conservation, environmental friendliness, and agricultural economic growth, as well as agricultural carbon emissions and carbon sinks, among which agricultural carbon emissions include carbon emissions from agricultural materials and carbon emissions from animal husbandry. In calculating carbon emissions from animal husbandry, five types of pigs, sheep, cattle, poultry, and rabbits were selected. A total of 18 crops, such as wheat, corn, rice, soybean, sweet potato, cotton, and oil, were selected for carbon sink calculation. Yuan, P. et al. measured the agroecological efficiency of 59 prefecture-level cities in the Yellow River Basin from 2000 to 2018 and concluded that the average efficiency showed a fluctuating upward trend, which was slightly different from the study in this paper[47]. The efficiency value obtained in this paper showed a slow downward trend in general, and the efficiency value in the downstream region was higher than that in the middle reaches, and the upstream region was the lowest. There are few existing studies on the impact of urbanization on agricultural low-carbon efficiency, and the research conclusions are quite different. In this paper, it is concluded that urbanization level has a significant positive impact on agricultural low-carbon efficiency in the upper, middle, and lower reaches of the Yellow River Basin. This may be due to the different measurement and analysis results obtained by scholars using different indicator systems, as well as the differences between the study area and the measurement, making the results incomparable. Therefore, it is urgent to study this area. The research area of this paper is still relatively macro, so in the future, more de-tailed and specific county-level data will be used for research, so as to more pertinently reflect the spatio-temporal change characteristics of local agricultural low-carbon efficiency and propose corresponding countermeasures and suggestions. In this paper, only a single population of urbanization is used to represent the level of urbanization. In the context of accelerating new-type urbanization and promoting high-quality agri-cultural development in China, especially in the Yellow River basin, a more diversified and comprehensive indicator system needs to be established in the future to make a more accurate evaluation of the level of urbanization. In addition, due to the availabil-ity and operability of data, this paper only selected some indicators to evaluate agri-cultural low-carbon efficiency, and with the continuous enrichment and change of the connotation of agricultural low-carbon efficiency, its index system needs to be further improved and amended in the future.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
Dear Authors,
I consider that the manuscript is focused on an interesting topic related to the analysis of the impact of urbanization dynamics on agricultural low-carbon efficiency in the Yellow River Basin using statistical analysis from 2000-2020. The importance of this study is related to the complex analysis based on super-DEA model, three-dimensional Kernel density model, Markov chain model, the panel Tobit model.
Key words: you should avoid using key words which are also in the title (eg. Yellow River Basin, low cabon efficiency in agriculture, urbanization.
Introduction:
In introduction statistical data about the case study should not be included. These details should be included in the description of the case study – a subsection of methodology.
Introduction should include a short presentation of the importance of the topic approach before going into specific details about your case study, taking into consideration that this topic is a particular problem faced by many countries.
At the end of the introduction, you should formulate the research questions in relation with the aim of the study and a synthetic presentation of the importance of the study.
You should also add the structure of the paper.
Methodology
You can include here a first subsection regarding your case study.
Regarding the presentation of the methods, you should include one or two sentences, in which you explain why you consider the chosen methods are relevant for the topic approached.
Results and Analysis
I recommend you to rename the section: Results and Discussion as you make also a critical interpretation of the results.
You should include in this section the subsections: 5.2. Policy suggestion and 5.3 Research limitation from the Conclusion section since this information is more suitable for discussion. Conclusion section may be shorter, because your study is extensive. Subsections: 5.2. and 5.3 can be added at the end of Results.
Conclusion and Suggestion
-this section can be rename simply conclusion as a result of the changes proposed in the previous section.
Minor comments:
On the first page there is letter R in the right part of the page that it should be deleted.
There is no reference in the text to Figure 1.
There is a repetition of the words low efficiency – see line: 426
Author Response
AE1: I consider that the manuscript is focused on an interesting topic related to the analysis of the impact of urbanization dynamics on agricultural low-carbon efficiency in the Yellow River Basin using statistical analysis from 2000-2020. The importance of this study is related to the complex analysis based on super-DEA model, three-dimensional Kernel density model, Markov chain model, the panel Tobit model.
Response: Thank you very much. In this paper, the agricultural carbon sink index is added as the expected output in the measurement of agricultural low carbon efficiency, and the impact of urbanization on agricultural low carbon efficiency in the Yellow River Basin is studied. Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript.
AE2: Key words: you should avoid using key words which are also in the title (eg. Yellow River Basin, low carbon efficiency in agriculture, urbanization.)
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have revised the keywords section to minimize the use of keywords in the title. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 29-Line 30)
Keywords: low-carbon; agriculture; spatial temporal heterogeneity; urbanization
AE3: In introduction statistical data about the case study should not be included. These details should be included in the description of the case study – a subsection of methodology.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have revised the introduction, but this paper not only takes the Yellow River Basin as an example, but also has very scientific and detailed empirical analysis, so a large number of figures are needed to prove it. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 47-Line 61)
In 2020, the total agricultural output value of the nine provinces in the Yellow River Basin was about CNY 2,633.46 billion, accounting for 32.94% of the total agricultural output value of the country. But at the same time, the agricultural development mode of the Yellow River Basin is extensive, the agricultural carbon emission is large, and the agricultural non-point source pollution has seriously affected the ecological environment of the Yellow River Basin [6]. According to the Bulletin of the Second National Pollution Source Census, in 2017, chemical oxygen demand, ammonia nitrogen, total nitrogen, and total phosphorus pollution in agricultural carbon emissions in the Yellow River Basin accounted for 80.6%, 40.9%, 53.0%, and 74.1% of the total pollutant emissions in the Yellow River Basin, respectively [7]. In addition, ecological problems such as vegetation destruction, soil erosion and soil degradation are very serious [8]. Since reform and opening, China's urbanization level has continuously improved. In 2020, China's urbanization level reached 63.89%, an increase of nearly 46% compared to1978.
AE4: Introduction should include a short presentation of the importance of the topic approach before going into specific details about your case study, taking into consideration that this topic is a particular problem faced by many countries.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have supplemented the importance of the research in the introduction by highlighting the particular problems facing the Yellow River Basin. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 39-Line 74)
According to statistics, agricultural carbon emissions account for about 25% of the total greenhouse gas emissions [2], which is one of the important components of China's carbon emissions, and improving agricultural low-carbon efficiency is an important way to achieve the "double carbon" goal [3].The Yellow River Basin is an important economic zone and agricultural production base in China, as well as an important ecological barrier in China [4]. Promoting the green modernization of its agriculture is of great practical significance for improving the ecological environment of the Yellow River Basin and achieving high-quality development [5]. In 2020, the total agricultural output value of the nine provinces in the Yellow River Basin was about CNY 2,633.46 billion , accounting for 32.94% of the total agricultural output value of the country. But at the same time, the agricultural development mode of the Yellow River Basin is extensive, the agricultural carbon emission is large, and the agricultural non-point source pollution has seriously affected the ecological environment of the Yellow River Basin [6]. According to the Bulletin of the Second National Pollution Source Census, in 2017, chemical oxygen demand, ammonia nitrogen, total nitrogen, and total phosphorus pollution in agricultural carbon emissions in the Yellow River Basin accounted for 80.6%, 40.9%, 53.0%, and 74.1% of the total pollutant emissions in the Yellow River Basin, respectively [7].In addition, ecological problems such as vegetation destruction, soil erosion and soil degradation are very serious [8]. Since reform and opening, China's urbanization level has continuously improved. In 2020, China's urbanization level reached 63.89%, an increase of nearly 46% compared to1978.The rapid increase in urbanization level can promote the transfer of agricultural surplus labor, improve the efficiency of agricultural resource allocation, and increase the total demand for agricultural products, but it may also include negative impacts such as agricultural non-point source pollution, ecological environment degradation and agricultural land consumption [9].Therefore, against the background of extensive agricultural production methods in the Yellow River basin, serious ecological environmental pollution, and accelerating urbanization process in China, it is of great practical significance to study the spatio-temporal evolution characteristics of agricultural low-carbon efficiency in the Yellow River Basin and whether the promotion of urbanization will affect the improvement in agricultural low-carbon efficiency. This will improve the development level of agricultural economy and promote ecological environmental protection in the Yellow River Basin, and provide relevant decision references for policy makers.
AE5: At the end of the introduction, you should formulate the research questions in relation with the aim of the study and a synthetic presentation of the importance of the study.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. In the last part of the introduction, we emphasize the significance and innovation of this study. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 165-Line 175)
Based on this, this paper uses the panel data of 75 cities in the Yellow River Basin from 2000 to 2020, uses the super-DEA model to measure the agricultural low-carbon efficiency in this special region more accurately, and establishes a three-dimensional kernel density model and Markov chain model to analyze the spatio-temporal evolution characteristics of agricultural low-carbon efficiency in the Yellow River Basin. In addition, the panel Tobit model is used to innovatively explore the relationship between urbanization and low-carbon agricultural efficiency., in order to provide references f to improve agricultural low-carbon efficiency and promote high-quality agricultural development in the Yellow River Basin.
AE6: You should also add the structure of the paper.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have supplemented the structure of the paper at the end of the introduction. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 176-Line 181)
This paper is organized as follows. The mechanism of influence of urbanization on the low-carbon efficiency of agriculture is introduced in the next section. The introduction of research methods and data usage is analyzed in Section 3. The analysis of the measurement, spatio-temporal evolution and the impact of urbanization on agricultural low-carbon efficiency in the Yellow River Basin is discussed in Section 4. Finally, some conclusions are given, and some policies are highlighted in Section 5.
AE7: You can include here a first subsection regarding your case study.
Response: Thank you for this helpful suggestion. According to your comments, I have added the article structure in the previous part. Additional steps may be repeated here. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
AE8: Regarding the presentation of the methods, you should include one or two sentences, in which you explain why you consider the chosen methods are relevant for the topic approached.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. In the first sentence of each research method, we supplement the reasons for choosing the method. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 238-Line 239，Line 280-Line 282，Line 334-Line 336)
In this paper, the super-DEA model is used to measure the agricultural low-carbon efficiency in the Yellow River Basin.
In this paper, the spatial correlation and evolution characteristics of agricultural low carbon efficiency were analyzed using the spatial Markov chain model, and the long-term evolution trend was predicted.
This paper uses the Tobit model to analyze the impact of urbanization on the low carbon efficiency of agriculture in the Yellow River Basin.
AE9: I recommend you to rename the section: Results and Discussion as you make also a critical interpretation of the results.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. There is already a discussion section below, so in order to avoid repetition, we have not changed the title. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
AE10: You should include in this section the subsections: 5.2. Policy suggestion and 5.3 Research limitation from the Conclusion section since this information is more suitable for discussion. Conclusion section may be shorter, because your study is extensive. Subsections: 5.2. and 5.3 can be added at the end of Results. This section can be renamed simply conclusion as a result of the changes proposed in the previous section.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We think that policy recommendations should probably not be included in the discussion section, we combine the study limitations with the discussion, and the policy recommendations are included in the study conclusions. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.（Line 924-Line 980)
5.2. Research conclusions
In this paper, the super-DEA model is used to measure the agricultural low-carbon efficiency of 75 cities in the Yellow River Basin from 2000 to 2020, and the nuclear density estimation method and Markov chain model are used to conduct an in-depth analysis of the spatio-temporal evolution of agricultural low-carbon efficiency. On this basis, the panel Tobit model explores the relationship between urbanization and agricultural low-carbon efficiency. Finally, the following conclusions and relevant policy recommendations are put forward as follows.
First, the overall level of agricultural low-carbon efficiency in the Yellow River Basin is low and has not reached the effective state, showing a slow downward trend. From a regional perspective, the level of agricultural low-carbon efficiency in the lower reaches > middle reaches > upper reaches showed a downward trend from 2000 to 2015, and gradually rebounded after 2016. The overall agricultural low-carbon efficiency in the Yellow River Basin is relatively low and has great potential for improvement. Therefore, we should attach importance to the application of science and technology in agriculture, promote the development of green agricultural modernization, change the previous extensive agricultural production mode, use organic fertilizers and low-carbon agricultural machinery and equipment, and use green high-tech innovations to improve resource utilization efficiency and reduce environmental pollution.
Second, the internal differences of the overall agricultural low-carbon efficiency in the Yellow River Basin decreased continuously during the sample period, and there was a significant spatial positive correlation. According to the traditional Markov chain, agricultural low-carbon efficiency has a negative trend of transferring to a low level on the whole, and tends to maintain the original state, and it is difficult to realize the leap-forward transfer between states. According to the spatial Markov chain, there is an obvious spatial spillover effect and "club convergence" phenomenon of agricultural low-carbon efficiency, and the high-efficiency area has a positive driving effect on the neighborhood area, while the low-efficiency area has a negative impact on the neighborhood area. Therefore, regional cooperation and exchanges should be strengthened. Cities with high agricultural low-carbon efficiency should play a positive driving role, share successful experiences with neighboring cities with low efficiency, share advanced low-carbon agricultural technologies and scientific research results, and improve agricultural production efficiency. Cities with low agricultural carbon efficiency should take the initiative to learn from neighboring cities with high efficiency, combine their own environment and specific development conditions, improve agricultural production and management methods, enhance agricultural low-carbon efficiency, and narrow the gap between them and neighboring cities. Specifically, long-term comprehensive real-time monitoring can be carried out through the establishment of a carbon emission pollution linkage early warning mechanism in neighboring regions so as to strengthen exchanges and cooperation between regions to improve agricultural low-carbon efficiency[48].
Third, in the Yellow River Basin as a whole, the urbanization level, multiple cropping index and agricultural economic development level all have significant positive impacts on agricultural low-carbon efficiency, while the level of energy-saving technology in agricultural production, the agricultural industrial structure, the agricultural scale level and government intervention have significant inhibitory effects on agricultural low-carbon efficiency. The influencing factors and directions of agricultural low-carbon efficiency in the upper, middle and lower reaches differ from those in the Yellow River Basin. More attention should be paid to the significant factors influencing agricultural low-carbon efficiency. This can promote the urbanization rate and the level of agricultural economic development, improve the crop planting structure, give play to the important role of the government in improving the agricultural ecological environment, rationally allocate financial funds to support agriculture, increase investment in agricultural ecological protection, encourage farmers to cultivate low-carbon awareness, and improve the level of energy saving technology in agricultural production. Moreover, improving the relevant legal system construction and institutional guarantee will promote agricultural low-carbon efficiency.
AE11: On the first page there is letter R in the right part of the page that it should be deleted.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have corrected the spelling of the words and the paper has been polished.（75693）And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
AE12: There is no reference in the text to Figure 1.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We supplemented the reference from Figure 1 in the article. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. （Line 187-Line 189)
The mechanism of influence of urbanization level on agricultural low-carbon efficiency can be mainly divided into positive and negative aspects (Figure 1).
AE13: There is a repetition of the words low efficiency – see line: 426
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have systematically polished the paper, corrected the language errors and improved the English language quality.（75693）And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors
Will urbanization affect the low-carbon efficiency of agriculture?-- Based on empirical evidence from the Yellow River Basin
This paper explores the possibilities for the improvement of urban agricultural practices to achieve "double carbon" goal in the Yellow River Basin through low carbon efficiency. It uses panel data from 2000 to 2020 and uses kernel density model and Markov chain model to measure and analyze the spatial-temporal evolution of agricultural low-carbon efficiency. It argues that this research is essential because agricultural carbon emissions account for about 25% of the total greenhouse gas emissions, and its amelioration is essential. It chose the Yellow River Basin because of
A. The important of this area for economic zone and agricultural production base in China.
B. Promoting the green modernization is of great practical significance for improving the ecological environment of the Yellow River Basin and achieving high-quality development.
C. The total agricultural output value of the nine provinces in the Yellow River Basin is about 42 2,633.46 billion yuan in 2020, accounting for 32.94% of the total agricultural output value.
Agricultural low-carbon efficiency is essential because urban population has exceeded the rural population from 2007 at the global scale and China’s overall urban population has just exceeded 63%. Thus, to optimize agricultural production technology, it is essential to reduce production mode and management measures to reduce carbon emissions, reduce environmental pollution, and promote the stable and healthy development of ecological environment. This rhetoric seems very appealing, however, it is hard to see these goals are achieved in this paper.
The paper has some theoretical importance, but it is hard to see its practical application. It neither uses any specific crops tied to specific carbon emission not it explains how much urban areas it covers. Additionally, the methodology presented is very unclear. Readers will not know what its application is to solve the real-world problems. It tries to present positive and negative aspects of agriculture which is just a basic theory that can be found in a textbook. These positive and negative aspects provided have no practical connotation and it is not tied to any specific study area, it is too vague.
This paper requires a thorough revision to illustrate the research findings with specific crop types and total urban areas covered in this research. Model wise, it sounds okay. Some specific technical glitches are given below:
Page 4, lines 165-185: It is not clear how urbanization will help in low carbon efficiency.
Page 4, lines 197-200: The 197 expansion of urban population increases the demand for high-carbon agricultural products such as meat, eggs and milk, resulting in a large amount of agricultural carbon emissions, which has a negative impact on the low-carbon efficiency of agriculture. What is the basis of this claim, it is not clear.
Page 6, lines 260-263 (0.25, 0.5): when 0.25 to 0.5 and 0.5 to 0.75 intervals are chosen, the value of 0.5 is counted twice. Likewise, there are other incidences that would have repeated values.
Page 2, line 47-51:
According to the Bulletin of the Second National Pollution Source Census, In [TYPO] 2017, chemical oxygen demand, ammonia nitrogen, total nitrogen and total phosphorus pollution in agricultural carbon emissions in the Yellow River Basin accounted for 49 80.6%, 40.9%, 53.0% and 74.1% of the total pollutant emissions in the Yellow River Basin, respectively [6].
Comments on the Quality of English Language
Moderate Engish correction is needed.
Author Response
AE1: Agricultural low-carbon efficiency is essential because urban population has exceeded the rural population from 2007 at the global scale and China’s overall urban population has just exceeded 63%. Thus, to optimize agricultural production technology, it is essential to reduce production mode and management measures to reduce carbon emissions, reduce environmental pollution, and promote the stable and healthy development of ecological environment. This rhetoric seems very appealing, however, it is hard to see these goals are achieved in this paper. The paper has some theoretical importance, but it is hard to see its practical application. It neither uses any specific crops tied to specific carbon emission not it explains how much urban areas it covers. Additionally, the methodology presented is very unclear. Readers will not know what its application is to solve the real-world problems. It tries to present positive and negative aspects of agriculture which is just a basic theory that can be found in a textbook. These positive and negative aspects provided have no practical connotation and it is not tied to any specific study area, it is too vague.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We supplement the practical significance of the research in the introduction. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. （Line 66-Line 74)
Therefore, against the background of extensive agricultural production methods in the Yellow River basin, serious ecological environmental pollution, and accelerating urbanization process in China, it is of great practical significance to study the spatio-temporal evolution characteristics of agricultural low-carbon efficiency in the Yellow River Basin and whether the promotion of urbanization will affect the improvement in agricultural low-carbon efficiency. This will improve the development level of agricultural economy and promote ecological environmental protection in the Yellow River Basin, and provide relevant decision references for policy makers.
AE2: This paper requires a thorough revision to illustrate the research findings with specific crop types and total urban areas covered in this research. Model wise, it sounds okay. Some specific technical glitches are given below: Page 4, lines 165-185: It is not clear how urbanization will help in low carbon efficiency.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. Urbanization promotes the low-carbon efficiency of agriculture by facilitating the transfer of surplus rural labor, supporting rural areas with capital, advanced technologies and concepts, and promoting increased demand for quality products and services. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. （Line 190-Line 211)
First, urbanization has a significant role in promoting the low-carbon efficiency of agriculture. On the one hand, the improvement in the urbanization level drives the increase in the proportion of secondary and tertiary industries, thus promoting the transfer of rural surplus labor force, improving the efficiency of agricultural land use and labor marginal output [20], promoting the specialization of agricultural development and the moderation of production scale [21], and thus improving the low-carbon efficiency of agriculture. On the other hand, improving the urbanization level will lead to a large number of high-quality labor population in cities and towns, which will transform the original agricultural producers into agricultural consumers, greatly increase the demand for high-quality life quality and agricultural products, and further promote the transformation of agricultural production mode from traditional extensive production to new green production [22], thus promoting low-carbon efficiency in agriculture. In addition, the rapid development of urbanization will also lead to a continuous reduction in agricultural arable land, but in the long run, the gradual return of urban capital to the countryside will be conducive to intensive and large-scale agricultural production and reduce production costs. At the same time, significant urban capital will flow into rural areas, bringing advanced production technology and management concepts to rural areas, promoting the development of agricultural technology and agricultural machinery, improving production conditions, reducing resource waste, promoting improved rural economic and ecological benefits, and contributing to improved low-carbon agricultural efficiency [23].
AE3: Page 4, lines 197-200: The 197 expansion of urban population increases the demand for high-carbon agricultural products such as meat, eggs and milk, resulting in a large amount of agricultural carbon emissions, which has a negative impact on the low-carbon efficiency of agriculture. What is the basis of this claim, it is not clear.
Response: Thank you for this helpful suggestion. The relevant explanation in this paper mentioned by you refers to the relevant literature of Cheng Linlin[18] and other scholars, which is similar to the explanation in this paper, so it can be considered that this statement is more reasonable. Specifically speaking, the increase in demand for agricultural products caused by the expansion of urban population, especially high-carbon products such as meat and their indirect consumption of food processing, will lead to more carbon emissions, thus inhibiting the improvement of low-carbon efficiency of agriculture. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
[18]Cheng,L.L.;Zhang,J.B.;He,K.different spatial impacts of agricultural industrial agglomerations on carbon efficiency: mecha-nism,spatial effects and groups differences. J.Journal of China agricultural University,2018,23,218-230.
AE4: Page 6, lines 260-263 (0.25, 0.5): when 0.25 to 0.5 and 0.5 to 0.75 intervals are chosen, the value of 0.5 is counted twice. Likewise, there are other incidences that would have repeated values.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have modified the four types of intervals in the agricultural low carbon efficiency numbers to ensure that no numbers are double-counted. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. （Line 291-Line 297)
In this paper, the agricultural low-carbon efficiency values(E) in the Yellow River Basin were divided into four types according to the following quartile: k=1 means low agricultural low-carbon efficiency (E≤0.25), k=2 means medium low agricultural low-carbon efficiency(0.25<E≤0.5), k=3 means medium high agricultural low-carbon efficiency (0.5<E≤0.75), and k=4 means high agricultural low-carbon efficiency (E>0.75).
AE5: Page 2, line 47-51: According to the Bulletin of the Second National Pollution Source Census, In [TYPO] 2017, chemical oxygen demand, ammonia nitrogen, total nitrogen and total phosphorus pollution in agricultural carbon emissions in the Yellow River Basin accounted for 49 80.6%, 40.9%, 53.0% and 74.1% of the total pollutant emissions in the Yellow River Basin, respectively [6].
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have corrected the case of the words, and the paper has been polished.（75693）And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
AE6: Comments on the Quality of English Language. Moderate English correction is needed.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We have systematically polished the paper, corrected the language errors and improved the English language quality. （75693） And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Comments and Suggestions for Authors
Lines 66-74:
I did not see any mention of specific crops to quantify how carbon efficiency is possible. It answers the broader question to support a macro theory but not at the micro level.
AE2: “First, urbanization has a significant role in promoting the low-carbon efficiency of agriculture. On the one hand, the improvement in the urbanization level drives the increase in the proportion of secondary and tertiary industries, thus promoting the transfer of rural surplus labor force, improving the efficiency of agricultural land use and labor marginal output [20], promoting the specialization of agricultural development and the moderation of production scale [21], and thus improving the low-carbon efficiency of agriculture. On the other hand, improving the urbanization level will lead to a large number of high-quality labor population in cities and towns, which will transform the original agricultural producers into agricultural consumers, greatly increase the demand for high-quality life quality and agricultural products, and further promote the transformation of agricultural production mode from traditional extensive production to new green production [22], thus promoting low-carbon efficiency in agriculture. In addition, the rapid development of urbanization will also lead to a continuous reduction in agricultural arable land, but in the long run, the gradual return of urban capital to the countryside will be conducive to intensive and large-scale agricultural production and reduce production costs. At the same time, significant urban capital will flow into rural areas, bringing advanced production technology and management concepts to rural areas, promoting the development of agricultural technology and agricultural machinery, improving production conditions, reducing resource waste, promoting improved rural economic and ecological benefits, and contributing to improved low-carbon agricultural efficiency [23].”
Are the authors talking about vertical farming in urban areas to increase greenery in the urban areas? Are they also talking about the Kuznets Curve concept that with the advancement in technology, pollution levels will be reduced in rural areas? This concept is not clear to me. I am not fully convinced with this logic.
AE3: “Thank you for this helpful suggestion. The relevant explanation in this paper mentioned by you refers to the relevant literature of Cheng Linlin[18] and other scholars, which is similar to the explanation in this paper, so it can be considered that this statement is more reasonable. Specifically speaking, the increase in demand for agricultural products caused by the expansion of urban population, especially high-carbon products such as meat and their indirect consumption of food processing, will lead to more carbon emissions, thus inhibiting the improvement of low-carbon efficiency of agriculture. I hope that I have modified and explained the manuscript enough, and it is to your satisfaction.”
I am not sure of this logic.
Comments on the Quality of English Language
Some corrections are needed.
Author Response
Responses to Reviewer
AE1: Lines 66-74: I did not see any mention of specific crops to quantify how carbon efficiency is possible. It answers the broader question to support a macro theory but not at the micro level.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. In the introduction part, we added the content about the quantification of agricultural low carbon efficiency, and explained the specific crops involved at the micro level. In addition, we added the specific content of the quantification of agricultural low carbon efficiency in the results and discussion part of the paper.And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 77-Line 79) (Line 363-Line 367)
Among them, the quantitative aspects of agricultural low-carbon efficiency mainly consider the large-scale crops planted in the Yellow River basin, including wheat, corn, rice, soybean, sweet potato, cotton, oil and so on. (Line 77-Line 79)
Agricultural carbon emissions include agricultural materials carbon emissions and animal husbandry carbon emissions. In calculating carbon emissions from livestock farming, five types of pigs, sheep, cattle, poultry and rabbits were selected. The calcu-lation of agricultural carbon sink mainly includes 18 crops such as wheat, corn, rice, soybean, sweet potato, cotton and oil. (Line 363-Line 367)
AE2: “First, urbanization has a significant role in promoting the low-carbon efficiency of agriculture. On the one hand, the improvement in the urbanization level drives the increase in the proportion of secondary and tertiary industries, thus promoting the transfer of rural surplus labor force, improving the efficiency of agricultural land use and labor marginal output [20], promoting the specialization of agricultural development and the moderation of production scale [21], and thus improving the low-carbon efficiency of agriculture. On the other hand, improving the urbanization level will lead to a large number of high-quality labor population in cities and towns, which will transform the original agricultural producers into agricultural consumers, greatly increase the demand for high-quality life quality and agricultural products, and further promote the transformation of agricultural production mode from traditional extensive production to new green production [22], thus promoting low-carbon efficiency in agriculture. In addition, the rapid development of urbanization will also lead to a continuous reduction in agricultural arable land, but in the long run, the gradual return of urban capital to the countryside will be conducive to intensive and large-scale agricultural production and reduce production costs. At the same time, significant urban capital will flow into rural areas, bringing advanced production technology and management concepts to rural areas, promoting the development of agricultural technology and agricultural machinery, improving production conditions, reducing resource waste, promoting improved rural economic and ecological benefits, and contributing to improved low-carbon agricultural efficiency [23].”
Are the authors talking about vertical farming in urban areas to increase greenery in the urban areas? Are they also talking about the Kuznets Curve concept that with the advancement in technology, pollution levels will be reduced in rural areas? This concept is not clear to me. I am not fully convinced with this logic.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. Our explanation of the positive impact of urbanization on low-carbon agricultural efficiency is not the impact of vertical agriculture in urban areas or the concept of Kuznets curve, but mainly reflected in the following three aspects: First, the employment gap and favorable living environment in cities and towns attract rural population to continuously gather in cities and towns, which effectively alleviates the problem of labor surplus in rural areas of the Yellow River Basin. Optimize the allocation of factors and resources, improve agricultural production efficiency; Second, the concept of environmental protection is transferred to left-behind farmers through the green agricultural product demand of urban farmers, prompting left-behind farmers to use green agricultural production methods to reduce environmental pollution; Third, with the passage of time, urban capital will gradually return to the countryside, bringing a large amount of capital, advanced technology and concept support, promote the development of green production technology in rural areas, and further reduce environmental pollution. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 179-Line 214)
First, urbanization has a significant role in promoting the low-carbon efficiency of agriculture. On the one hand, the improvement in the urbanization level drives the increase in the proportion of secondary and tertiary industries, thus promoting the transfer of rural surplus labor force, optimizing the allocation of resources and factors, improving the efficiency of agricultural land use and labor marginal output [20], promoting the specialization of agricultural development and the moderation of production scale [21], promoting the advancement of agricultural technology and improve the efficiency of agricultural technology [22], and thus improving the low-carbon efficiency of agriculture. On the other hand, the improvement of urbanization level will lead to a large number of high-quality workers gathering in cities and towns, transforming from agricultural producers to agricultural consumers. With the increase of per capita disposable income of urban residents, it will promote the upgrading of residents' consumption level, which may increase the consumption demand for high-quality life quality and green agricultural products [23]. It makes farmers pay more attention to the protection of agricultural ecological environment and reduce the use of pesticides and other chemicals in production. This concept of environmental protection is transmitted through the connection between urban farmers and left-behind farmers, thus promoting the transformation of agricultural production mode from traditional extensive production to new green production and promoting the improvement of low-carbon efficiency of agriculture [24]. In addition, the rapid development of urbanization will make a large number of urban capital gradually return to the countryside in the long run, which is conducive to agricultural intensive and large-scale production and reduce production costs, bringing advanced production technology and management concepts to rural areas, promoting the development of agricultural technology and agricultural machinery, improving production conditions, reducing resource waste, promoting improved rural economic and ecological benefits, and contributing to improved low-carbon agricultural efficiency [25].
AE3: “Thank you for this helpful suggestion. The relevant explanation in this paper mentioned by you refers to the relevant literature of Cheng Linlin[18] and other scholars, which is similar to the explanation in this paper, so it can be considered that this statement is more reasonable. Specifically speaking, the increase in demand for agricultural products caused by the expansion of urban population, especially high-carbon products such as meat and their indirect consumption of food processing, will lead to more carbon emissions, thus inhibiting the improvement of low-carbon efficiency of agriculture. I hope that I have modified and explained the manuscript enough, and it is to your satisfaction.”
I am not sure of this logic.
Response: Thank you for this helpful suggestion. We thank your comments which helped us improve the quality of this manuscript. We further elaborated on the theoretical logic that urbanization leads to the increase in the demand for high-carbon agricultural products of urban population, which in turn has a negative impact on the low-carbon efficiency of agriculture, and added two related literatures [28][29]. And all revisions are clearly highlighted by using the “Track Changes” function in Microsoft Word, so that changes are easily visible to you. I hope that I have modified and explained the manuscript clearly enough, and it is to your satisfaction. (Line 229-Line 239)
On the other hand, the non-agricultural employment of a large number of rural people has brought an increase in per capita income, and their diet structure, life and con-sumption pattern are also changing [28]. The food consumption demand has shown a new trend of health and diversification. The expansion of urban population has re-duced the demand for food and increased the demand for agricultural products such as meat, eggs and milk. Thus, the production of agricultural products such as meat, eggs and milk is increased. Since the carbon emissions generated by the consumption of ag-ricultural products such as meat, eggs and milk with the same weight are higher than that of grain consumption [29], more agricultural carbon emissions will be generated, which will have a negative impact on the low-carbon efficiency of agriculture.
