Nitrogen Load Of Agricultural Nonpoint Source In Zhanghe Upstream Basin

Zhanghe located in the southwest of the Haihe Basin,is the main tributary of the South Canal in Haihe Basin.Zhanghe upstream basin is located in the junction of shanxi,hebei and henan provinces.With a long time serious shortage of water resources,zhanghe upstream basin supplied water resource could not meet the social demand.water environment is deteriorating result from many sewage outfall and soil erosion is serious Zhanghe upstream basin.Consequantly,water ecology health and social economic sustainable developmentis have affected greatly.To resolve those problems,the improvement export coefficient model applied in the basin to estimate the nitrogen loads from agriculture non point source in this paper,the result as follow :Nitrogen delivered-to-rivers loads for agriculture non point source pollution is2422.22t/a.and the proportion of nitrogen delivered-to-rivers loads from field cropsland,vegetable cropland and garden plots are 86%,11% and 3% respectively among the total nitrogen delivered-to-rivers loads from crop farming.The rate of nitrogen delivered-to-rivers loads from bodymanure and rural domestic sewage are 12% and88% respectively in the total nitrogen delivered-to-rivers loads root in rural life.And from big livestockmanute,pigmanure,sheepmanure and poultrymanure are 63%,36%,1% and 0.08% respectively among the total nitrogen delivered-to-rivers loads originate from livestock and poultry breeding.The contribution rate,93%,of nitrogen delivered-to-rivers loads from livestock and poultry breeding is the most part of the total nitrogen delivered-to-rivers loads from agriculture non point source pollution.And 5%~8%,from rural life and the part of rate from crop farming is lettle.At the same time,ArcGIS applied in Zhanghe upstream basin to simulate the nitrogen loads from agriculture non point source.The spatial distribution characteristics of agricultural non point source nitrogen pollution and the sensitivity of export coefficient model are analyzed.And Verifies the critical importance of the export coefficient to the exportt coefficient model.