我国农业面源污染的时空分异研究

Spatial- temporal variation of agricultural non- point source pollution in China

农业面源污染已成为我国环境污染的重要组成部分,并对农业生产、经济发展带来了重大威胁,从国家层面分析农业面源污染的时间、空间分布特征,为我国农业提供基于区域污染规律的污染防治和环境治理的政策完善着力点。选取全国农业面源污染数据分析污染物时序变化特征并对样本进行聚类分析。结果表明:我国农业化肥投入、农田固体废弃物及畜禽排泄物,以及由它们产生的TN、TP、COD三类排放物都总体上随时间呈增长趋势,且存在着显著的地区差异;除个别省份,我国农业面源污染程度(污染源和污染物两个角度)在空间上呈以华北、中部地区为核心,污染程度向外辐射递减,且经济发达地区和农业发达地区的污染更为严重的分异特征。亟需全面结合地区经济社会和农业发展状况,准确把握区域发展差异,因地制宜、适时调整和完善农业环境政策。

Agricultural non- point source pollution has become an important part of environmental pollution in our country,and posing a major threat to agricultural production and economic development. Analyzing spatial-temporal variation of agricultural non- point source pollution can provide policy perfection focus for agricultural non- point source pollution prevention and control based on regional pollution regularity. This study calculated total amount of pollutants using the data of national agricultural non- point source pollution,and analyzed temporal variation characteristics of pollutants. Furthermore,this study analyzed spatial variation of agricultural non-point source pollution using clustering method. Results showed that there were growing trend over time generally and significant regional differences on agricultural fertilizer input,farmland solid waste,poultry excrement,and TN,TP,COD emissions produced by them. Agricultural non- point source pollution in our country from two angles of pollution sources and pollutants existed similar spatial variation except for several provinces. The spatial variation was that pollution level showed outward radiation decline with northern and central China as the core,and the pollution was more serious in economically developed areas and agriculture developed areas. It needs to grasp accurately the differences of regional development,adjust measures to local conditions,timely adjust and improve the agricultural environment policy by fully combined with regional social economy and agricultural development.