Research on variation of non-point source pollutant of field in Qingtongxia Irrigation District

An experiment was conducted to research the non-point source pollutant of field in qingtongxia irrigation area, and its variation features was also analyzed. The results showed that the rate of pollutants' concentration in water of the paddy field during the crop growing season was in the order of salinity, in agricultural ditch of the paddy field which is in the order of salinity, and in agricultural ditch of the dry field which is in the order of . The salinity concentration in field changes greatly. The content and loss quantity of TP are rarely small. The nitrogen loss is mainly . The variation process of pollutants' concentration in field was closely related to fertilization, irrigation process, the crop growing season and so on.