Principle Of Contaminant Release From Sediment In Urban Lakes And Its Application In Water Quality Model

Shallow lakes playing an important role in urban ecological environment, but polluted sediment block the harnessing progress of aquatic environment. It's significant for restoring lake ecological system to strengthen the research of release rule from sediment and control methods. Numerical simulation is one of important technologies in water resource planning, the precision of model cannot be ensured because it's difficult to ascertain the veracity of parameters, some ways must be created to improve it.The main contents discussed in this paper are as follows:(1) The releasing principle of lake sediment are summarized through the simulated experiment of pole-core sample in Xuanwu lake, and ration study on the relationship between releasing rate and factors are also taken on.(2) Through the statistics analyze of test data, we can select the factors which affect the releasing rate markedly, and educe the equations based on influencing factors according to the exchange principle between water and soil, then the static release coefficient will easily be gained.(3) A two-dimension water quality model, which coupled with sediment, was adopted to forecast the effect of water diversion in Xuanwu lake. The practicability of static release coefficient was validated by comparing the computer result and monitoring data.This paper provide train of thoughts to ascertain the coefficients by relating the physical and numerical simulation, and also analyses the cooperative effect of environmental conditions on sediment releasing, in order to provide gist for decision-making on the controlling of endogenesis in lake.