An estimation and evaluation of non-point source (NPS) pollution in the Yellow River Basin

It is necessary to assess NPS pollution loads in the Yellow River Basin in the national water resource synthesis plan. Using Remote Sensing and Geographic Information System techniques, the study has been carried out to analyze water and soil pollution data in the Yellow River Basin in 2000. The results are as follows: (1) The total nitrogen (TN) and total phosphorus (TP) loads in the form of NPS pollution are greater than the point source pollution in 2000; (2) Agriculture is the key source of TN and TP NPS pollution, mainly distributed in the Weihe River, the Fenhe River, and the Ningmeng irrigation regions; (3) In the pasturing areas, culture raising contributes much of the NPS pollution; (4) The impact of TN in urban and rural areas is relatively less than that of TP for the same areas throughout the Yellow River Basin; (5) The load of nitrogen from erosion is greater than the phosphorus load.