Empirical analysis of agricultural economic growth and planting non-point source pollution emissions from the perspective of spatial effects

Agricultural resources and environment are the basic resources and necessary conditions for the development of agricultural production and realization of agricultural economic growth. Analyzing the relationship between agricultural economic growth and planting non-point source pollution from the perspective of spatial effects can help to explore a new direction for prevention and control of planting non-point source pollution, and provide theoretical support for promoting the implementation of the policy of prevention and treatment of planting non-point source pollution. Based on the provincial panel data from 2000 to 2019, this study used the equal-standard pollution load method to measure the planting non-point source pollution emissions; and used the spatial Durbin model to empirically analyze the spatial effect of agricultural economic growth, consumption capacity, technological progress, agricultural modernization level, risk perception, financial support, disaster situation, and industrial structure on the emission of planting non-point source pollution, and to split the spatial effect of the influencing factors into direct and indirect spatial effects. The results are as follow: 1) A significant positive global spatial autocorrelation among the planting non-point source pollution in 31 provinces (cities, autonomous regions) was noted. In 2019, the spatial pattern was characterized by “high-high” and “low-low” aggregations, and the agglomerations were mainly in large agricultural provinces and economically developed areas. 2) The planting non-point source pollution had a significant negative spatial spillover effect, with a spatial lag coefficient of −0.11, and agricultural economic growth had a significant effect on the region and adjacent regions in a mutually exclusive direction. 3) The results of the effect of decomposition showed that the direct and indirect effects of agricultural economic growth, consumption capacity, technological progress, agricultural modernization level, and risk perception were significant at 5% confidence level. Among them, agricultural economic growth had a relieving effect on planting non-point source pollution discharge, and the estimated coefficient was −0.175; however, it had an aggravating effect on the planting non-point source pollution discharge in the adjacent area, with an estimated coefficient of 0.397. Therefore, by paying more attention to the guiding role of the significant influencing factors, such as agricultural economic growth, technological progress, and financial support, local governments should actively give full play to their own advantages and linkage with adjacent areas to play a spatial interaction, carrying out new agricultural technology training, and establishing an effective supervision and management system to achieve balanced development. From the perspective of the research object, this study analyzed the relationship between agricultural economic growth and agricultural non-point source pollution from the perspective of the planting industry, and it enriches existing research on planting non-point source pollution and improves the attention to the prevention and control of planting non-point source pollution. Moreover, the emissions of planting non-point source pollutants were calculated based on the emissions of ammonia nitrogen, chemical oxygen demand, total nitrogen, and total phosphorus from agricultural chemical fertilizer and farmland solid waste, and this helps to ensure the comprehensiveness of the data required for empirical analysis and can more accurately describe the relationship between agricultural economic growth and planting non-point source pollution emissions. The combination of the two dimensions of time and space to analyze the relationship between agricultural economic growth and agricultural non-point source pollution emissions can provide a new analytical perspective and play an important role in putting forward more practical countermeasures and suggestions.