The improved MEI model for forecasting TP reference concentration in Lake Taihu basin

Abstract

太湖流域湖泊污染严重,非常有必要建立相应的水质基准以便于湖泊水体的保护与修复.根据太湖流域12个受人类影响较小的湖库及太湖早期的总磷、总碱度、平均水深等数据建立了MEI(morphoedaphic index)模型,通过对模型中总磷与总碱度、平均水深因子的相关关系进行分析,并结合太湖流域湖库水深较浅的特征,提出了确定太湖流域湖库水体中总磷参照浓度的改进MEI模型.将该模型应用于太湖,得到太湖总磷参照浓度为0.025 mg/L.研究结果旨在丰富我国水体营养物基准的确定方法,并为太湖流域水体富营养化的控制提供理论依据,同时为长江中下游类似湖库水质基准的建立提供技术支撑.;In view of the status of serious pollution in Lake Taihu basin,it is necessary to establish an appropriate water quality criteria to protect and restore the lake environment.According to the data on total phosphorus,total alkalinity,mean water depth in 12 reservoirs and lakes with little human influence in Lake Taihu basin as well as the early-time (pre-industrial) data in Lake Taihu,a morpho edaphic index (MEI) model was built.The correlations between TP and two factors,which are mean water depth and total alkalinity in MEI model,were analyzed,respectively.Considering the fact that all the lakes in Lake Taihu basin are shallow, the improved MEI model was proposed.Then the improved MEI model was used to determine TP reference concentration in Lake Taihu.The result showed that the reference concentration of TP was 0.025 mg/L.This study is aimed at diversifying the methods of nutrient criteria research in China,and providing theoretic support for eutrophication control in Lake Taihu basin as well as establishing nutrient criteria for similar lakes in the middle and lower reaches of the Yangtze River.s