Abstract:Nitrogen and phosphorus are the major contributors to eutrophication of water.The dynamic output of non-point resources in Lanhe watershed located at Fenhe River's upstream was studied in the present paper using the method for non-point source pollutants revenue and expenditure analysis.The total nitrogen and phosphorus export of watershed were mostly influenced by the runoff amount of the watershed.The retention rate was mostly determined by plants and microbial organisms in the watershed.The value of correlative coefficient between the total nitrogen and retention rate was 0.724 and the corresponding dates between two of total phosphorus,and retention rate,runoff amount are more than 0.7.The average error rate was controlled within 10 percent through simulating the watershed's TN and TP with no-point resource's export and import analysis method.The correlative coefficient between total nitrogen simulated data about export concentration and load and their monitored date were 0.895 and 0.924,respectively. The correlative coefficient between the total phosphorus simulated data about export concentration and load and their monitored data were 0.896 and 0.997,respectively.