Coupling Relationship Between Organic Matter And Phosphorus In Lake Sediments Eutrophication

Eutrophication has been one of the most serious environmental disasters in water by far. Water Eutrophication is the result of joint action by many physical factors, chemical factors and biological factors. Its formation is a complex and dynamic process, not only with a rich source of nutrients, but also closely related to the systemic effects of the environment. Phosphorus is the primary limiting-factor in eutrophication. The environment of terrestrial freshwater lakes as an example, the concentration, distribution, source and the coupling relationship between organic matter and phosphorus in the aquatic ecosystem was studied. The following conclusions were obtained:1. The distribution of TP and various forms of phosphorus in different lakes’ sediments was analyzed.The four different types of lakes including Tai Lake, Chao Lake, Baiyang Lake and Lugu Lake were researched,it found that the TP content Tai Lake> Chao Lake> Lugu Lake> Baiyang Lake. Phosphorus forms in these lakes are different is related to the environment of the lake. The phosphorus content in the northern Tai Lake is higher than that in the southern Lake. The content in the western half of Chao Lake is higher than that in the southern half of the lake, and from north to south has a reduced trend. The district in Baiyang Lake influenced by upstream pollution has a higher phosphorus content than the lake district center. Lugu Lake in western Lake District has a higher phosphorus content than in the eastern Lake. Advantage phosphorus forms in Tai Lake, Chao Lake, Lugu Lake is respectively for Ferromanganese of Chelated phosphorus, iron and aluminum oxidation state phosphorus, calcium and magnesium bound phosphorus, active organic phosphorus. The bioavailable phosphorus’s proportion in TP in different degree of pollution in sediments:the heavily polluted area moderately contaminated areas> not contaminated area. The iron and aluminum oxidation state a maximum contribution to bioavailable phosphorus.2. Distribution characteristics and sources of organic matter and its components in different lake sediments were studied.Analysis of organic matter in lake sediments found that Baiyang Lake and Lugu Lake belong to the high content of organic matter lakes, and Chao Lake and Tai Lake belong to the low organic matter content. Lakes with high organic matter have a higher humus proportion than low organic matter lakes. The proportion of fulvic acid in sediments is higher than in the soil humus. Water-soluble organic matter in different lakes is mainly derived from biological sources. The fulvic acid and humic acid component in Chao Lake and Tai Lake are close to the land-side sources. Baiyang Lake and Lugu Lake are more inclined to the biological source.3. Coupling relationship between the organic matter and phosphorus was researched.Coupling relationship of organic matter and phosphorus showed that the release risk of Bioavailable phosphorus is independent to the level of organic matter concentration of the lake.The potential phosphorus release risk is mainly determined by the binding forms of organic matter and phosphorus. The organic matter in Tai Lake and Chao Lake have a significantly influence on the risk for release of bioavailability of phosphorus. The water-soluble organic matter in Lugu Lake affects the release of organic phosphorus. Baiyang Lake organic matter has no effect on release of phosphorus.Through this study, not only obtained a more in-depth and comprehensive understanding of biogeochemical cycling of phosphorus in the lake ecosystem of Tai Lake, Chao Lake, Baiyang Lake, and Lugu Lake. It provided scientific and theoretical basis for the governance of eutrophication in different types of lake.