Spatial Distribution Characteristics And Pollution Source Analysis Of The Main Pollutants In Nanfei River

Research shows that the input of exogenous pollution is the main pollution source of Chaohu Lake,especially the pollution input of Naifei River,as an incoming river of Chaohu Lake.According to the strategy of “ water treatment before lake governance,harness a river before water treatment”.The study of pollution and governance of Naifei River is imminent.In this paper,a comprehensive survey of pollutant emission from Nanfei River and the amount of pollutants discharged to the Chaohu Lake is researched,then analysis the pollution source structure,taking the content of COD,NH3-N,TN and TP and their time-space distribution characteristics in the Nanfei River as the main line,using the nemerow index method to evaluate the water quality of the Nanfei River,and based on the partition of Nanfei River,using multivariate statistical principle to analysis the pollution source.The following results are obtained.(1)The results of investigation and analysis of pollutants show that the main pollution factors of Nanfei River is COD?NH3-N?TN?TP.At the same time,the evaluate results of nemerow index method also show that the water quality of Nanfei River is mainly between the class V water and inferior class V water.(2)The results of the temporal and spatial of pollutants show that,from the time point of view,it is coincidence with the trend as follows : dry season > temperate season > wet season;as a whole,the pollution characteristics of Nanfei River is obvious by the impact of urban pollution characteristics.The variation trend of the water-quality index of Nanfei River show initially increased and then decreased,conbined with the pollution source investigation and analysis and water compliance plan of Nanfei River,in order to effectively control the pollution of Nanfei River,we should be take the control of nitrogen and phosphorus in Banqiao River,Ershibu River and Dianbu River input as the main.(3)On the basis of the partition,the pollution sources are identified by principal component analysis according to the factor loading of variables and the factor scores of monitoring sections.83.33% of pollution of point sources of A area are from the organic and nutrients;70.16% of pollution of point sources of B area are from the organic and nutrients;73.63% of pollution of the non-point source of C area are from agricultural nutrients and biochemical effects.Through principal component multiple linear regression analysis,the pollution contribution rate of the water-quality index of each type is obtained,The pollution degree of main factors to water quality can be better estimated.It can provide technical support for scientific and rational management of rivers.