Simulation on Change Law of Runoff, Sediment and Non-point Source Nitrogen and Phosphorus Discharge under Different Land uses Based on SWAT Model: A Case Study of Er hai Lake Small Watershed

[摘要] The Er yuan watershed of Er hai district is chosen as the research area, the law of runoff and sediment and non-point source nitrogen and phosphorus discharges under different land uses during 2001 to 2014 are simulated based on SWAT model. Results of simulation indicate that the order of total runoff yield of different land use type from high to low is grassland, paddy fields, dry land. Specifically, the order of surface runoff yield from high to low is paddy fields, dry land, grassland, the order of lateral runoff yield from high to low is paddy fields, dry land, grassland, the order of groundwater runoff yield from high to low is grassland, paddy fields, dry land. The orders of sediment and nitrogen and phosphorus yield per unit area of different land use type are the same, grassland> paddy fields> dry land. It can be seen, nitrogen and phosphorus discharges from paddy fields and dry land are the main sources of agricultural non-point pollution of the irrigated area. Therefore, reasonable field management measures which can decrease the discharge of nitrogen and phosphorus of paddy fields and dry land are the key to agricultural non-point source pollution prevention and control.

[发布机构] Chang Jiang River Scientific Research Institute(CRSRI), Wuhan, HUBEI; 430010, China^1;State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, HUBEI; 430072, China^2

[效力级别] 经济学

[关键词] Agricultural non-point pollution;Agricultural non-point source pollutions;Different land use types;Groundwater runoff;Nitrogen and phosphorus;Runoff and sediments;Small watersheds;Surface runoff yields