Research On The Agricultural Environmental Efficiency In The Urbanization Process Of China

Agriculture is the basic industry of the national economy and the root of agricultural economic growth is the improvement of agricultural production efficiency.In the process of urbanization in our country,the relationship between urban and rural areas has undergone many adjustments,the environmental pollution is once more severe,and the regional economic ties are increasingly close.Under this background,integrating environmental factors into the framework of traditional agricultural production efficiency,measuring the agricultural production efficiency,studying the characteristics of temporal and spatial changes and influencing factors can reflect the mode and path of agricultural economic growth,and testing the effect of the state's implementation of environmental pollution control,which will have important practical significance for safeguarding the national food security,changing the mode of agricultural economic growth,and protecting the ecological environment.Module one is the measurement of the real level of agricultural production efficiency in the process of urbanization without considering environmental factors.Starting from the connotation of urbanization,this paper attempts to theoretically analyze the influence mechanism of urbanization development on agricultural production efficiency.Then it combines Super-SBM-DEA model with SFA model to improve the traditional three-stage DEA model.Using this model,it measures the agricultural production efficiency before and after stripping the external environment of urbanization,and regards the stripped efficiency as the real efficiency.Finally,it compares the timing characteristics and regional differences of the two groups of agricultural production efficiency.The study found that the actual level of agricultural production efficiency is higher than the efficiency value under the urbanization environment,and urbanization will affect agricultural production efficiency.In the process of narrowing the regional differences in urbanization,the level of agricultural production efficiency will be improved.Under the effect of "spatial proximity effect" of urbanization,agricultural production efficiency presents spatial agglomeration characteristics,while the spatial dependence characteristics of agricultural production efficiency are no longer obvious after the urbanization environment is stripped.Module 2 is the static and dynamic measurements of agricultural environmental efficiency in the process of urbanization.The inventory survey method was used to calculate agricultural non-point source pollution as an undesired output.Based on the global production technology,the SBM-DEA model and the Global-Malmquist-Luenberge productivity index were used to measure the agricultural environmental efficiency level and its growth and changes.The overall characteristics and regional differences were compared with the traditional agricultural production efficiency.The study found that the agricultural environmental efficiency showed an upward trend,but was lower than the traditional agricultural production efficiency.The excessive discharge of agricultural non-point source pollution caused greater efficiency loss to agricultural production,but the growth of agricultural environmental efficiency was higher than that of the traditional agricultural efficiency.Judged from the speed of development trend,the effect of agricultural pollution control was beginning to show.The average agricultural environmental efficiency in the four major regions is ranked a s eastern region > northeast region > western region > central region from high to low.Considering environmental factors,the efficiency gap between eastern region and other regions will be widened.After 2008,the growth of agricultural environmental efficiency in central region will be accelerated,surpassing western region,and the gap will be gradually wider.Module 3 is an analysis of the spatial and temporal characteristics of agricultural environmental efficiency evolution in the process of urbanization.On one hand,it analyses the agricultural environmental efficiency of provinces and cities in time series,describes their changing trend characteristics and studies the time lag effect.On the other hand,based on the spatial statistical analysis method,using the global and local spatial correlation diagnostic techniques,the spatial agglomeration and spatial heterogeneity characteristics of agricultural environmental efficiency and agricultural environmental productivity were investigated,and their spatial effect differences were compared.The study found that agricultural environmental efficiency has the characteristics of lag in time and obvious global positive spatial correlation,and shows the characteristics of spatial agglomeration as a whole with the trend of strengthen.Agricultural environmental efficiency and environmental productivity both have local spatial correlation.Module 4 is a spatial econometric analysis of factors affecting agricultural environmental efficiency in the process of urbanization.Firstly,on the basis of theoretical analysis of the influence mechanism of urbanization on agricultural environmental efficiency,the transmission function of social and economic structural changes and spatial spillover efficiency,the factors affecting agricultur al environmental efficiency at the natural level,economic level,institutional level and regional level are analyzed,and at the economic level the effects of urbanization development on the quality of production factors,agriculture industrial structure and technological input are discussed.Furthermore,four kinds of spatial weight matrices,namely,adjacent spatial weight,geographic distance weight,economic distance weight and population migration weight,respectively set up to study the spatial lag effect in different adjacent areas,then construct a static spatial Dubin panel econometric model and analyze the direct effect and spatial spillover effect of the influencing factors.Finally,the static model is expanded to a dynamic spatial Dubin panel measurement model to analyze the effects of time-space lag and other influencing factors on agricultural environmental efficiency.The research finds that the static model shows that agricultural environmental productivity has negative spatial spillover effect and will inhibit the growth of agricultural environmental productivity in neighboring regions.Urbanization will produce "Siphon effect" on agricultural production resources in neighboring regions and release negative spatial spillover effect.The improvement of human capital level and the adjustment of agricultural structure are conducive to the improvement of local agricultural environmental productivity.The increase of technological input level has a significant pulling effect on the productivity of local agricultural environment,and will produce a positive spatial spillover effect on neighboring regions.Fiscal policies for supporting agriculture and pollution control show more "crowding-out effect" on local impacts,which is not conducive to the growth of agricultural environmental productivity.The dynamic model shows that the impact of agricultural environmental productivity in both local and neighboring regions has time lag.However,unlike the static model results,the diffusion effect of agricultural environmental productivity lag depends on spatial proximity,which is still a negative effect between neighboring regions in geographical location,while it is a positive effect between regions with close socio-economic ties.The spatial spillover effect of urbanization development on agricultural environmental productivity has a significant promoting effect among regions with close economic and social ties,but has no obvious effect on the neighboring regions with geographical location.Because population urbanization brings spillover of rural human capital,the improvement of rural human capital level is not conducive to the improvement of local agricultural environmental productivity,but will promote the growth of agricultural environmental productivity in neighboring areas.Economic urbanization can increase technological investment,which have spatial spillover effects on the improvement of agricultural environmental productivity and concretely speaking it is a dynamic evolution process.