The simulation of nitrogen (N) and phosphorus (P) pollution load structure in Bali Lake basin was performed by SWAT model using the spatial and attribute database acquired through social survey and statistical data. The model was applied and validated based on the data of meteorology, runoff and water quality from 2010 to 2014. The spatial-temporal distribution of N and P in the basin was also studied. The results showed that the urban life was the most important source of N and P load, following by agriculture and livestock breeding pollution source, and the least was industry pollution source. The annual TN and TP loads were mainly concentrated in flood season (from May to September) which took up nearly 55% of the whole year load. As the amount of precipitation increased, TN and TP loads increased during flood period, which was mainly due to the increasing of non-point rural living water and agricultural fertilization pollution source with scouring action of the heavy rainfall during flood season. The spatial distribution of N and P was centered on the Jiujiang county, Xunyang and Lushan district as the urban agglomeration area affected by urban sewage pollution.

基于SWAT模型, 通过社会调查和统计数据获取模型所需的空间数据及污染源输入数据, 构建江西八里湖流域的氮磷负荷模拟模型, 并利用当地 2010—2014年的气象、径流和水质观测资料, 对模型进行率定和验证。依据该模型, 分别在时间和空间上对研究流域的氮磷污染物分布进行模拟。结果表明: 流域氮磷污染主要来自城镇生活源、农田施肥和畜禽养殖, 工业源最少; 氮磷负荷主要集中在汛期(5—9月), 占全年的55%, 汛期污染负荷主要受农村生活和农业施肥的面源影响, 随着降水增大等因素导致冲刷作用增强, 径流中总氮和总磷的负荷也随之增大。氮磷等营养物负荷主要分布在流域内人口密集的九江县、浔阳区和庐山区, 与对应区域大量城镇生活污水的排放相关。