Huang Laxi small watershed,which locates at Longsheng town in central sichuan hilly region,was considered as the research object in this paper.With the practical measured and survey data,the water environmental capacity and the quantity of non-point pollutant were discussed.The results indicated that from August to next January,there were three months,particularly in August,the water quality condition was exceed standard in Huang Laxi,and the amount of TN should be reduced 19.36 t/a.Requires special attenti...