Through the study on soil erosion and agricultural non-point source pollution to the water body of the Fangbian valley in Nanjing,a new research approach,integrated quantitative monitoring,was introduced.It adopts the "3S" technique to gain necessary data to satisfy factors of the mathematical model of soil erosion monitoring.First,obtain accurate amount of soil loss through quantitat ive monitoring of soil erosion,and then work out an accurate non-point pollution sources distribution map and figure out pollution load to the reservoir based on the results obtained in the previous step and the annual mean soil nutrient contents under different land uses.Precision of the monitoring is verified through evaluation of the measured bedloads at the upstream and downstream hydraulic monitoring stations,while pollution load into the reservoir is determined through test and analysis of water samples and measured volume of runoffs.In 2002,the precision of monitoring of soil erosion was 93.62% in the studied area,and of the pollution load of total phosphorus into the water body from non-point sources was 77.79%.The results initially show that the method of integrated quantitat ive monitoring is characterized by precision,quickness and economization.