Simulation study of nitrogen and phosphorus loss with runoff under different land Use in northern Jiangsu province

Non-point source pollutants have been accumulated for a long time, and the soil is always easy for eroding in northern area of Jiangsu province. The pollutants flood into the river with rainfall runoff in flood seasons, which has become the one of the important reasons that causes water quality not stable in this area. Three typical lands in northern water-deficient area of Jiangsu province were studied on nitrogen and phosphorus losses in artificial rain-runoff simulator, which rainfall intensity was set 80mm/h (rainstorm). The results showed that the loss amounts of runoff and sediment followed the order that paddy field > orchard > woodland under the same rainfall condition. The amounts of nutrient losses were different among three types of land. The losses of TN (total nitrogen) in runoff followed the order that paddy field > orchard > woodland, and the TP (total phosphorous) followed the order that orchard > paddy field>woodland. The characters of different nitrogen and phosphorous forms loss were significant difference in different types of land surface soil. The most of TN and TP were lost through suspended particle.