| In September 2020,the Chinese government declared that "China will continue to make extraordinary efforts to scale up its nationally determined contributions and adopt even more forceful policies and measures and strive to peak carbon dioxide emissions before 2030 and achieve carbon neutrality before 2060",namely the solemn commitment of "carbon peak" and "carbon neutrality".In October 2022,the report of the 20 th National Congress once again emphasized that "Chinese-style modernization is the modernization in which people and nature coexist in harmony","It is high time to speed up the green transformation of development mode,implement the comprehensive conservation strategy,develop green and low-carbon industries,advocate green consumption,and promote the formation of green and low-carbon production mode and lifestyle".Under this scenario,it is urgent to continuously broaden the path of reducing emissions and increasing foreign exchange,and accelerate the low-carbon transformation of all walks of life.Among them,the agricultural sector is not only one of the main sources of greenhouse gas emissions,but also the most sensitive industry to climate change.The carbon peak and carbon neutrality goal cannot be achieved without the deep participation of the agricultural sector.Promoting the low-carbon transformation of agricultural production has become one of the important academic frontiers in agricultural economic research.With the rapid development of industrialization and urbanization,agricultural and rural areas are facing the dilemma of short of agricultural land area and increasingly lack of labor force.Innovation in agricultural management system and appropriate expansion of agricultural land scale have become an unavoidable leading trend in China’s agricultural development.In line with the policy,many discussions on agricultural land scale are mainly from the perspectives of production cost,input-output,production efficiency and so on.In addition,studies have also been carried out on fertilizers intensity as well as that of pesticides,the application of green production technology and so on,providing a substantial research basis for the advancement of this study.However,from the perspective of agricultural carbon emission reduction,there are still the following research deficiencies: On the one hand,existing studies on agricultural land scale and agricultural low-carbon production behavior are still mainly focused on the use of agricultural materials,lacking the analysis of different stages within the whole process.On the other hand,limited by the data availability,the overall relationship between agricultural land scale and agricultural carbon emissions needs to be empirically tested,and how to decide agricultural land scale against the goal of agricultural carbon reduction targets remains to be answered.Therefore,following the logic of "Reality Analysis-Theoretical AnalysisEmpirical Test-Policy Enlightenment",this study was carried out from both theoretical and empirical perspectives.Based on systematic review of relevant theories and literature,combined with the macro data,this study has deeply analyzed the status quo,policies,and challenges of Chinese agricultural carbon emission.In the empirical analysis part,this study uses the data of rural fixed observation points and micro data of China Land Economic Survey(CLES),and according to the logical clue of "Agricultural Materials Purchase-Agricultural Materials Use-Waste Disposal-Overall Impact",comprehensively uses the panel fixed effect model,instrumental variable method,binary selection model and other methods.This paper paid attention to the following questions:(1)In the purchasing stage,how does agricultural land scale affect the proportion of purchasing agricultural materials through formal channels?(2)In the using stage,how does agricultural land scale affect the intensity of chemical fertilizer application,and what role does agricultural mechanization play?(3)In the disposal stage,what impact does agricultural land scale have on the recycling behavior of agricultural waste?(4)Most importantly,what is the relationship between agricultural land scale and agricultural carbon emissions? Is there an optimal agricultural land scale against the goal of "agricultural carbon emissions reduction" ? Built on the above analysis,the main conclusions are as follows:(1)There was a significant positive relationship between the agricultural land scale and the proportion of purchasing agricultural materials through formal channels,and this result was still robust after considering the endogeneity.Heterogeneity analysis showed that this positive effect was more significant in households with low land fragmentation or no access to the internet.With the expansion of agricultural land scale,farmers would raise their need for more diversified agricultural materials with higher quality.Meanwhile,the budgetary constraints of farmers have been relaxed and their bargaining power have been improved as well,which positively affected the ability and willingness of farmers to purchase agricultural materials from formal channels.(2)The expansion of agricultural land scale significantly reduced the intensity of fertilizer application,and this result was still robust after considering the endogeneity.Heterogeneity analysis showed that this negative effect was more significant in households whose main business is planting,or mainly grow cash crops,or with smaller land scale.The analysis of the influence mechanism showed that agricultural mechanization played a significant mediating role,which means that the expansion of agricultural land scale would indirectly reduce the intensity of fertilizer input by promoting agricultural mechanization input.On the other hand,for small scaled farmers,the social machinery service played a significant moderating role.(3)Different from the purchasing and using stages,the expansion of agricultural land scale significantly discouraged the farmers to recycle agricultural waste,and this result was still robust after considering the endogeneity.The heterogeneity analysis showed that the negative effect of the sample farmers in the more developed areas was lower than that in the less developed areas.The negative effect was lower for younger farmers than that of older samples.The results of mechanism test showed that social norms and economic incentives played a significant role in regulating and promoting the recycling of agricultural waste by farmers under the condition of given agricultural land scale.As far as this study concerned,the moderating effect of social norms is more obvious.(4)On the whole,the relationship between agricultural land scale and agricultural carbon emissions intensity per mu presented a stable and significant inverted U-shaped relationship.Ceteris paribus,agricultural carbon emission per mu reaches the maximum when the land scale is around 6.19 mu.On the other hand,agricultural land scale and agricultural carbon productivity showed a steady horizontal S-shaped relationship.Ceteris paribus,agricultural carbon productivity reaches the minimum when the land scale is around 8.15 mu,and reaches the maximum when it was around36.27 mu,which can be treated as the moderate scale against the goals of "carbon reduction" as well as "production promotion".The analysis of heterogeneity showed that the land scale corresponding to the maximum point was different in the south and the north while maintaining the relationship.Under the existing productivity conditions,agricultural carbon emission intensity of food crops decreased with the expansion of agricultural land scale,but agricultural carbon productivity would increase.The mechanism analysis showed that agricultural land scale affected agricultural carbon emission intensity by influencing the relative structure and input intensity of agricultural carbon emission sources.Based on the above main conclusions,this study put forward the following policy recommendations:First,adhere to the orientation of appropriate scale operation and promote the modernization of agricultural production in an orderly manner.Nationwide,a small scale of agricultural land may constrain the dual goals of agricultural "carbon reduction" and agricultural production.Therefore,it is necessary to actively guide small farmers to carry out land replacement and integration,help the construction of high-quality land,to promote the normalization of the purchase stage of agricultural materials and break the constraints of land scale matching and mechanical utilization efficiency faced by the reduction of chemical fertilizer.On the other hand,all regions should adapt to local conditions rather than blindly pushing for land expansion.For example,when agricultural carbon emissions per mu reach the maximum in the south and the north,the corresponding land scale is different.Therefore,each region should promote moderate scale based on its own land endowment,phenological conditions and other actual conditions.Second,multiple measures should be taken to promote low-carbon transition in all stages of agricultural production.In the purchasing stage,we should regulate the management of purchasing agricultural materials and strengthen the training and supervision of dealers,to eliminate the phenomenon of unlicensed management and sale of inferior agricultural materials,and effectively protect the interests of farmers.In the using stage,in addition to relying on existing policies and technical support to continue to promote the reduction of chemical fertilizers,it is also necessary to speed up the green and efficient development of agricultural machinery.Research and development institutions should further strengthen the development of agricultural machinery towards high efficiency intelligent,large-scale,environmental-friendly,and economical.In the last stage,government should strengthen the education and training the publicity on the harmfulness of agricultural waste disposal and the necessity of recycling,improve farmers’ comprehensive cognition of agricultural waste,and guide farmers to actively recycle by strengthening the guidance and constraints of informal systems such as social norms.Third,in a systematic and holistic way,the goal of "carbon reduction" should be incorporated into the guidance of relevant agricultural policies,and clear agricultural carbon emission reduction policies should be comprehensively introduced.For example,the government may further introduce carbon reduction-oriented goal into the agricultural land protection subsidies.What’s more,the government can also guide farmers to purchase green and efficient agricultural machinery through agricultural machinery subsidies,or escort the smooth progress of agricultural carbon emission reduction with economic incentive policies.For another example,the target of "carbon reduction" can be incorporated into the diet structure to promote the reform of residents’ diet structure and guide the diversification of food planting.In summary,the marginal contributions of this study are mainly in the following two aspects: First,based on the new realistic goal of "carbon emission reduction",this study tried to pay much attention to the impact of agricultural land scale on the lowcarbon agricultural production behavior within different stages.Secondly,based on the analysis of the overall relationship between agricultural land scale and agricultural carbon emissions,the suggested area of agricultural land scale from the perspective of carbon emission reduction was provided.In the future analysis,this study can be further expanded from the following aspects: First,in terms of data indicators,the calculation of core indicators still requires for further precision and refinement.Second,in terms of empirical methods,newly frontier empirical models should be applied to alleviate the potential endogenous problems.Thirdly,from the perspective of research,not only can the narrow sense of agriculture be expanded to the broad sense of agriculture(farming,forestry,husbandry,side-line production and fishery),but also the carbon sequestration attribute of agriculture can be included in the calculation system of net carbon emissions. |
