Temporal And Spatial Distribution Of Nitrogen And Phosphorus In Hongfeng Lake And Analysis Of Influencing Factors

Lake eutrophication is one of the main water pollution problems in China,which has become an important factor restricting the national production and living standard.Hongfeng Lake,a representative lake in the Yunnan-Guizhou Plateau,is an important drinking water source in Guiyang.Nitrogen and phosphorus are important indicators that affect the eutrophication of lake water bodies,Their spatial and temporal distribution directly affects the stability and change of water quality.This paper takes Hongfeng Lake as the research water body,the temporal and spatial distribution characteristics of nitrogen and phosphorus in the water body of Hongfeng Lake were monitored and monitored during the period from 2017 to 2018,the areas and time periods in which the nitrogen and phosphorus pollution in the lake area are heavier are determined,and analyze its influencing factors and environmental effects.On this basis,based on the calculation of the eutrophication index,assessing the eutrophication of Hongfeng Lake.The research results can provide a scientific basis for the water environment assessment and protection of Hongfeng Lake.The main conclusions are as follows:(1)The temporal and spatial distribution characteristics of nitrogen and phosphorus in the water body of Hongfeng Lake,its concentration in the Hongfeng lake presented spatial characteristics of that the upstream exceeded the downstream and the south over the north.with seasonal changes as flood season > normal season > drought period and the overall vertical distribution as bottom > middle > surface.(2)Water quality parameters such as p H,water temperature,DO(dissolved oxygen),precipitation and transparency all affected the spatial and temporal distribution characteristics of nitrogen and phosphorus in Hongfeng Lake.The correlation index was 0.7~1?(3)The nitrogen-phosphorus ratio of Hongfeng Lake is between 41.1 and 200.2,and the water eutrophication index(TLI)is between 43.1 and 45(in terms of season),in the intermediate stage of eutrophication.Phosphorus is the main limiting factor for the eutrophication of the whole lake in Hongfeng Lake.(4)Houwu and Yangchang River have more nitrogen and phosphorus in the water,the release of endogenous phosphorus in these two sites is more serious,it should be used as a key area for monitoring the eutrophication of water bodies.