Reassessment and analysis of agricultural non-point source pollution in China: 2009-2023

Assessing the fundamental status of agricultural non-point source pollution in China, identifying its regional variations, and summarizing its dynamic evolution patterns hold significant theoretical and practical implications for advancing the construction of ecological civilization. Although some scholars have estimated China's agricultural non-point source pollution, significant controversy remains regarding the emission indicators constituting this pollution and their conversion coefficients. This paper recalculates agricultural non-point source pollution using officially published calculation manuals, results more aligned with China's specific realities. Furthermore, based on the assessment of China's agricultural non-point source pollution from 2009 to 2023, this study employs the Dagum Gini decomposition method and kernel density analysis to examine regional variations and dynamic evolution patterns. The findings reveal:(1) From 2009 to 2023, China's agricultural non-point source pollution emissions showed an overall upward trend. While pollution from Crop cultivation declined significantly, the rapid expansion of Livestock farming led to more severe agricultural non-point source pollution. Livestock farming is currently the primary source of agricultural non-point source pollution in China, with its chemical oxygen demand emissions continuing to rise.(2) Although regional disparities are pronounced, the overall differences in agricultural non-point source pollution show a fluctuating contraction trend, with inter-regional variations being the primary driver of these overall differences. (3) The overall dispersion of agricultural non-point source pollution in China has increased, a characteristic evident to varying degrees across different economic areas, grain functional areas, and agricultural functional areas. These findings contribute to a comprehensive understanding of the current distribution and evolving trends of agricultural non-point source pollution, aiming to provide a reference basis for achieving green and sustainable agricultural development in China.