Abstract:The N and P accumulation characteristics of soil in Songhuaba Reservoir are studied.Results show that the average content of total N of soil(0-20 cm) in the whole reservoir is 1.79 g/kg;NH4-N,13.55 mg/kg;and NO3-N,7.29 mg/kg.Landuses ranked from the high content of total N to the low are in turn the agricultural land,fruit land and vegetable land;NH4-N,in turn the fruit land,agricultural land and vegetable land;and NO3-N,in turn the fruit land,vegetable land and agricultural land.The average content of total P of soil(0-20 cm)is 1.60 g/kg,and available phosphate,10.36 mg/kg.Landuses ranked from the high content of total P to the low are in turn the agricultural land,fruit land and vegetable land;available phosphate,in turn the vegetable land,agricultural land and fruit land.The content of total N in the rivers entering the reservoir is in the 2nd grade,but falls into the 5th grade near the reservoir.The content of total P of the rivers is in the 2nd grade,and the highest content of total P is in the 3rd grade.However,the water quality falls into the 3rd grade near the reservoir.