【摘要】 对重庆市2000—2020年间的土地利用数据进行分析，基于改进的输出系数模型和核密度分析工具，开展全市面源污染风险测算和集聚程度分析。研究发现：（1）2000年、2010年、2020年TN的无风险和极高风险等级比例分别为6.09%→2.05%→10.04%和9.2%→9.79%→6.86%，表明2000—2020年期间全市面源污染风险呈现先增加后降低的趋势。（2）2010—2020年期间面源污染风险降低显著，风险等级均值在4以上的乡镇由19个减少到7个，风险等级均值在2以下的乡镇由38个上升到82个。（3）核密度分析结果显示2000—2020年期间面源污染的高风险区域的集聚程度存在降低趋势，尤其在各区县的城区以及渝东北城镇群和渝东南城镇群的退耕还林区域。更多还原

【Abstract】 The research analyzes the land use data of Chongqing from 2000 to 2020, and carries out the calculation and agglomeration degree analysis of non-point source pollution risk in Chongqing Based on the improved output coefficient model and nuclear density analysis tool. The study found that:(1) the proportions of no risk and extremely high risk levels of TN in 2000, 2010 and 2020 were 6. 09%→2. 05%→10. 04% and 9. 2%→9. 79%→6. 86% respectively, indicating that the risk of non-point source pollution in Chongqing showed a trend of " first increasing and then decreasing" from 2000 to 2020.(2) During 2010—2020, the risk of non-point source pollution decreased significantly, the number of townships with an average risk level of more than 4 decreased from 19 to 7, and the number of townships with an average risk level of less than 2 increased from 38 to 82.(3) The results of kernel density analysis show that the agglomeration degree of high-risk areas of non-point source pollution has a decreasing trend from 2000 to 2020, especially in the urban areas of districts and counties and the areas of returning farmland to forest.更多还原