Abstract：Based on the monitoring with MODIS data, the DPeRS model and algae bloom (AB) information were extracted and were used to assess nitrogen (N) and phosphorus (P) diffuse pollution (DP) and AB characteristics at pixel scale. Results showed 1) the yearly production of total nitrogen was 1900.3t in 2010 and 846.5 t were discharged. The total phosphorus production was 244.1t and the discharge load was 76t. 2) Agriculture contributes mostly the N-DP, and the water loss and soil erosion had great effect on P-DP. 3) The spatial-temporal feature analysis on N/P-DP loads and AB frequency confirmed that the N/P-DP related to AB. The AB happening lagged the DP firstly and after AB reaching the maxim. The DP and AB had the same temporal trend. The spatial distribution of AB matched well with DP. The correlation coefficient of bloom areas and NP loads was 0.45. 4) The scenarios analysis was analyzed with DPeRS model due to the dependency between DP and AB . The four scenarios could reduce N/P-DP 50% with reducing the fertilizer application 30%, improving the decontamination rate of urban and livestock refuse to 80% and rural life to 60%.
