The Variations of Nitrogen and Phosphorus Concentrations in Longchuan River-a Tributary of Jinsha River

The study was carried out in Chuxiong station from 2007 to 2009,in order to illustrate characteristics of nitrogen and phosphorus.The mean concentration of total nitrogen(TN) were 1.088 ～ 3.834 mg/L,and mean content of total phosphorus(TP) was about 0.091 ～ 2.036 mg/L,accounted for 39.4 percent to 93.7 percent,and more than 93.6 percent of the total phosphorus was in form of particle phosphorus(PP).TN、NH4 +-N and NO3--N were correlated well with water discharge first and then deviation,Conclude that the various forms of nitrogen in Longchuan River comes from the farm pollution.There existed positive relationships between total phosphorus and water discharge;therefore,soil erosion control should be an effective countermeasure in limiting nitrogen and phosphorus loss in the rainy season.