描述：There are many polders around Chaohu lake.Agricultural activities dominate these polders which drain important non-point source pollutants to their receiving water:Chaohu lake.To understand nutrient export from these areas,a typical polder was chosen to make a detailed study.Water discharge was measured for the four pumping periods in the summer of 2008 and the outflow of one of these events was sampled for analysis of Total Nitrogen(TN), ammonia and nitrate and Total Phosphorus(TP).The results showed that of the 552mm total summer rainfall,which represent half of the total annual rainfall,258mm had been drained out by pumping during the four rainstorm events.Under the co-effect of dilution and purging, the concentration demonstrated temporal variation for the four indicators.The Event Mean Concentration(EMC)of TN and TP reached 1.16mg-N/L and 0.12mg-P/L respectively, attaining eutrophic-hypereutropic level.A rough estimation of the loads of TN and TP during the four events were roughly estimated by total drainage and the EMC.The loads, 3.16kg-N/ha and 0.33kg-P/ha respectively for TN and TP,were negligible for agriculture but could be a considerable treat to its final receiving water:the Chaohu lake.Further studies will focus on the detailed processes,spatial and temporal variation of nutrient export and the sources quantification for the purpose of an optimally integrated water and nutrient export management in these polder areas.