| Lake sediments, where nutrition accumulation and exchange take place, are the complex transporter for the water. The border transportation between water and sediments is an important factor which influences the over richment of the lake. Phosphus is one of the constricting factors causing the nutrition enrichment. In the water body, where the outer phosphorus could be controlled, the distribution of Phosphus in the sediments is important for the growth of the sea organisms, especially the growth and breed of the algae. It also plays an important role to promote the nutrition over-enrichment of the lakes. Phosphorus has many patterns and differs according to the lake location, biological condition and the input of outer space. In this study, we choose the sediments of the lakes in eastern plain and mainly focus on seven characteristic lakes located in the down stream of Changjiang River as well as investigated eighty sediments samples. We used the strategy of analyzed the data got from the wild monitering and compared it with the history records in order to study the distribution pattern of the phosphorus in the area, the difference of the phosphorus in the aspect of shape and content, and the realtion of it between the micro-organism and enzyme. We hope this would provide the basic data for the phosphorus contamination control in the classic area.We investigated the content distribution patter of the division district with different nutrition over-enrichment in Poyang Lake and Tai lakes and found that TP variation in the surface sediments of the Poyang Lake is 0.010%~0.094% and the average is 0.046%. It decreases from south to north. The overall content of phosphorus in Tai lake is 0.035~0.115%, and the average TP value is 0.058%, which is higher than the average value of Poyang Lake and is near the lake body. The history trend behaved slowly augment though some variation.The content of TP in the sediments of eastern lake differs largely,but it mainly matains in the form of Ca-P, De-P, Fe-P and Occ-P, which takes 58% to 87% of the TP content. With the increase of of TP, the amount of Ca-P, De-P, is increasing, Occ-P do not change too much. The amount of Asd-P and Al-P is lower and it stays relatively stable. The Po sediments in Tai Lakes, East Lake and South Lake mainly exsit in the form of moderate Po and the content is about58.6~241.9 mg/kg.However, the Po sediments in Poyang Lake, Dongting Lake and Junshan Lake mainly stayed in non-active form, which take the amount of 47%~64.9% of the overall content. It differs in the shape and content of the organic Phosphorus, non-organic Phosphorus as well as the enzyme activity of the samples. The related research shows that the four types of enzyme is largely related to the transformation of the organic phosphorusAccordingly, the phosphorus content and shape distribution in the sediments of east plain differs according to the different contamination level. Among them, in the lakes that behaves over enrichment of the nutrition, phosphorus mainly in the state of active phosphorus and the active phosphorus content is related to the available phosphorus and effective phosphorus. Meanwhile, in the research of the activity of the enzyme, in the period of the higher enzyme activity, the content of the organic phosphorus decreases. If we do not control the phosphorus in the lake, it will increase and the active phosphorus would get into the water body and would be used by the algea. Therefore, reducing the inner phosphorus burden is very important for controlling the over enrichment of nutrition.
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