Sensitivity Analysis on Environmental Capacity Model of Nitrogen and Phosphorus for Lake and Reservoir

摘要

Taking a certain large water supply reservoir as example, this paper applies homa solution of lake perfect mixing attenuation model to analyze lake volume, lake staying time and degradation coefficient's effect on water environment capacity of total nitrogen and total phosphorus. The elastic coefficients are used as sensitivity indicators to discuss the above tbree model parameters' contribution rates to environmental capacity. The contribution rates of lake volume, staying time and degradation coefficient to total nitrogen capacity are respectively 36%, 2go% and 35%, and the contribution rates to total phospborus capacity are respectively 26%, 43% and 31%. The results show that the variation of model parameters can change dramatically dilution, degradation and displace capacity, and the change will affect the total environmental capacity. From the average value of elastic coefficient, each model parameter has great contribution to total nitrogen and total phosphorus environment capacity.