Research on Water Quality Changes in Dongting Lake

According to the monitoring data of Dongting Lake from 1992～2010 year,water quality,eutrophication state and main pollution indicators in Lake Dongtinghu were evaluated and analyzed.The results show that Lake Dongtinghu is mostly polluted by nitrogen and phosphorus,and water quality is deteriorated with eutrophication.Although chemical oxygen demand in water phase of Lake Dongtinghu decreased after remediation in 2007,concentrations of total nitrogen and total phosphorus is still on an upward trend,which result in significant increases of chlorophyll a concentration and phytoplankton abundance.