『Abstract
　There were many differences between rivers and lakes such as flow velocity, hydraulic retention time, water vegetation community and other chemical-physical factors that may lead to different characteristics of sedimentary phosphorus. In our research, sedimentary phosphorus fractions and its phosphorus adsorption differences between the lower Nansi Lake and its main inflow rivers were compared. The results showed that the contents of NaOH-P, Org-P, IP-P, and TP in lake sediments were obviously higher than those in its inflow river sediments while HCl-P had no obvious difference between them. Based on analysis, the unstable NaOH-P would accumulate in lake sediments, while it is difficult for it to retain in sediments of rivers because of a high frequency of flood flows and unstable bed sediments. In addition, water vegetation communities were helpful in the accumulation of Org-P in lake sediments. From phosphorus adsorption experiments results, the Ceqc (equilibrium concentration of phosphorus release/adsorption) of lake sediments was higher than that of river sediments. It was indicated that sedimentary phosphorus would be more easily released from lake sediments than river sediments. So in future more work should be focused on internal P loading from lake sediments release.

Keywords: Inflow rivers; Nansi Lake; Phosphorus adsorption characteristics; Sedimentary phosphorus fractions』

Introduction
Materials and methods
　Study sites
　Sediment sampling and analysis
　Sedimentary phosphorus fractions
　Phosphorus adsorption kinetics experiments
　Phosphorus adsorption isotherm experiments
Results and discussion
　Sedimentary phosphorus fractions
　Phosphorus adsorption kinetics process
　Phosphorus adsorption isotherms process
Conclusions
Acknowledgments
References