WANG Jingfu¹, CHEN Jingan¹, LUO Jing², ZHANG Hong¹, YU Pingping³

（1. State Key Laboratory of Environmental Geochemistry, Institute of geochemistry, Chinese Academy of Sciences, Guiyang 550081;
2. China Aerospace Construction Group Co., Ltd, Beijing, 100071;
3.Guizhou University, College of resources and environmental engineering, Guiyang 550025; ）

Abstract: Phosphorus（P）released from sediments is considered to be an important source of P in lake waters, but currently quantitative researches on fluxes of internal-P loading are still lacking. In this study, comparative studies on the methods of flux estimation of internal P release, e.g. field survey analysis, simulating experiment and the diffusion model were investigated to accurately estimate the contribution of the internal P flux in Lake Hongfeng. Rough contributions of different pollutant sources could be obtained by field survey in macro scale, but the results often have big error and uncertainty, as the harsh requirements of the working method are hard to be met practically. Since the physical and chemical structure of the sediments is destroyed during the sampling and cultural experiment, it is difficult to estimate accurately by the simulating experiment method. The diffusion model method has advantages in quantitative flux estimations. It is worth noting that high-resolution data of P at the sediment-water interface is crucial for reliable and quantitative calculation based on the diffusion model method. Our estimation results show that the flux of internal P release in Lake Hongfeng is reasonably high, accounting for 22%~46% of the total P in overlying waters. Therefore, in order to prevent the lake eutrophication fundamentally, it is necessary to 1) strengthen the external pollution governance, and 2) reduce the release of internal P earnestly.

Keywords：Sediment; Internal phosphorus; Release flux; Lake Hongfeng

EARTH AND ENVIRONMENT Vol.46, No.1, Tot No.321, 2018, Page 1-6