Measurement And Spatial-temporal Evolution Of Agricultural Green Total Factor Productivity In Major Grain-producing Areas

Major grain-producing areas are important grain production bases in China and play an important strategic role in ensuring national grain security and dynamic balance between supply and demand of agricultural products.According to statistics,the grain output in major grain-producing areas reached 524 million tons in 2019,accounting for more than 78 percent of China’s total grain output and about 60 percent of the country’s rural population.Agricultural production in major grain-producing areas has an important impact on stabilizing grain prices,raising farmers’ incomes and promoting the development of agriculture,rural areas and farmers.In recent years,grain output and agricultural economy in major grain-producing areas have grown rapidly.However,the long-term extensive production mode driven by high input of factors and high consumption of resources has resulted in the loss of agricultural factors,ecological environment deterioration and resource shortage.On the one hand,a large amount of agricultural film residue,excessive use of pesticides and fertilizers and improper treatment of rural solid waste have caused great harm to water resources and cultivated land resources.On the other hand,agricultural carbon emissions are approaching the peak,the utilization rate of agricultural inputs is low,the follow-up of grain increase is weak,and the agricultural production mode in major grain-producing areas is in urgent need of upgrading and transformation.In 2019,the No.1 Document of the CPC Central Committee proposed to strengthen the strategy of innovation-driven development,promote green agricultural development,and shift agriculture from increasing production to improving quality.The 14 th Five-year Plan for The Green Development of Agriculture further points out that accelerating the overall green transformation of agriculture and continuously improving the rural ecological environment.The measurement of agricultural green total factor productivity can comprehensively measure agricultural economic growth and resource and environment constraints,and effectively reflect the agricultural production efficiency more in line with the actual situation.Measuring agricultural green total factor productivity is of great significance to solve the resource and environment problems in the agricultural development process of main grain-producing areas.In view of this,in this thesis,agricultural carbon emissions and agricultural non-point source pollution composite index were taken as undesired outputs,and the dynamic change indices of agricultural GTFP and its decomposition in 13 major grain-producing provinces from 2002 to 2019 were measured by combining improved EBM model and ML index method.The spatial characteristics of agricultural GTFP were further investigated by using Moran index.On this basis,the kernel density estimation and Markov chain analysis method were used to explore the dynamic evolution trend of agricultural GTFP.Finally,the optimization potential of agricultural GTFP was analyzed by the redundancy rate of each input and output index.The research conclusions were as follows:(1)The comprehensive evaluation analysis showed that agricultural GTFP was closer to the real agricultural production efficiency.From 2002 to 2019,agricultural GTFP in major grain-producing areas fluctuated in an "M" shape,with a weak overall growth rate.(2)The analysis of regional differences showed that the agricultural GTFP of major grain-producing areas was significantly different among regions.At the provincial level,Hebei province had the highest annual average agricultural GTFP,while Inner Mongolia had the lowest.At the regional level,the main agricultural production areas in the Yangtze River Basin had the best agricultural green production effect,followed by the Huang-Huai-Hai region,and finally the northeast Region.(3)The characteristics of exploratory spatial agglomeration showed that agricultural GTFP had a negative spatial correlation in the long term.The agricultural GTFP of one province had a different trend with that of its neighboring provinces,and the spatial agglomeration of agricultural GTFP gradually changed from strong to weak.(4)The dynamic evolution trend showed that the kernel density curve showed a "double peak" distribution in 2019,and the agricultural GTFP showed a trend of polarization.By Markov analysis,it is found that the diagonal probability of Markov transition probability matrix is generally larger than the off-diagonal probability,and it is difficult to realize the leap improvement of agricultural GTFP in major grain-producing areas.(5)Optimization potential analysis shows that the three indexes with the greatest optimization potential of agricultural green input and output in major grain-producing areas are labor input,machinery input and carbon emission output.Finally,based on the results of empirical research and combined with the strategic needs of green agricultural development and high-quality development,this thesis proposes countermeasures and suggestions to establish and improve environmental supervision and prevention mechanisms,promote green and intensive agricultural production,and improve regional cooperation and interaction mechanisms.