基于Copula函数与经验频率曲线的富营养化风险分析

富营养化问题是我国湖泊面临的重要问题。太湖作为我国东部最大的淡水湖泊，附近城市供水水源地，其富营养化问题直接关系到苏州、无锡、江阴、湖州等环太湖城市的饮用水安全。选取浮游动物生物量、浮游植物生物量和叶绿素作为浮游生物数量的3个指标，绘制经验频率曲线，并采用Copula函数将其进行有效联结，从而得到太湖不同分区的富营养化风险评估。结果表明，太湖西北部湖区富营养化较为严重。

Eutrophication Risk Assessment Based on Copula and Empirical Frequency

Eutrophication problem is an important issue of lakes in China. Taihu Lake,the largest freshwater lake in eastern China,is a source of water supply of adjoining city. Its nutrient links to directly the drinking water safety of Suzhou,Wuxi and so on. Zooplankton biomass,phytoplankton biomass and chlorophyll were selected as indicators of plankton,rendering empirical frequency curve,and using Copula function to be effectively linked to obtain the number of lake plankton in different zones risk assessment. The results showed that the eutrophication of northwest Taihu Lake is more serious.