基于土壤流失的农业面源TN和TP排海系数估算

以黄河三角洲为典型研究区，通过分析区域地表污染物流失风险与入海通量的关系，构建了海岸带农业总氮（TN）和总磷（TP）面源污染排海估算模型.在此基础上，计算了包含水田、水浇地和旱地等耕地类的TN和TP面源污染排海系数，验证表明输出系数估算结果较好.研究区耕地的TN和TP排海系数分别为18.33 kg·（hm²·a）^-1和1.02 kg·（hm²·a）^-1，在夏季面源污染负荷较高.子流域尺度较大的耕地类农业面源污染负荷主要位于支脉河、广利河和小岛河管控区域.TN和TP总负荷较大的行政区主要位于北部黄河口镇和永安镇；较大的单位面积负荷在西南部.因此，需要关注农业面源污染的时间效应，同时协调社会经济发展，从子流域和行政单元的角度制定综合性面源污染防控策略，陆海统筹治理海域污染.

Estimation of Agricultural Non-point Source TN and TP Export Coefficients Based on Soil Loss

Taking the Yellow River Delta as a typical research area, we constructed a coastal agricultural TN and TP non-point source pollution estimating model by analyzing the relationship between the surface soil pollutant loss risks and the monitored pollutant flux into the sea. On this basis, TN and TP non-point source export coefficients of paddy fields, irrigated land, and dry land were calculated, and the verification showed that the estimated export coefficients were acceptable. In the study area, the TN and TP export coefficients into the sea of arable land were 18.33 kg·(hm²·a)^-1 and 1.02 kg·(hm²·a)^-1, respectively. The agricultural non-point source pollution loads of arable land were relatively high in summer. The sub-basins with larger agricultural non-point source pollution loads were mainly located in the control areas of the Zhimai River, Guangli River, and Xiaodao River. The administrative regions with larger total agricultural TN and TP loads were mainly in the northern Huanghekou Town and Yong''an Town, and areas with larger loads per unit area were in the southwest. Therefore, it is necessary to pay more attention to the temporal effects of agricultural non-point source pollution, simultaneously coordinate the social and economic development, and formulate comprehensive agricultural non-point source pollution prevention and control strategies from the perspective of sub-basins and administrative units. This will allow us to improve the offshore pollution status from the perspective of land and sea coordination.