Effect of ecological engineering on the nutrient content of surface sediments in Lake Taihu, China

Ecological engineering was carried out in Meiliang Bay of Lake Taihu beginning in 2003 in order to improve water quality. There were two main objectives: to improve the growth environment for macrophytes, and to restore macrophyte assemblages. We examined surface sediments once per month beginning in April 2005 to study the response of sediment nutrient content to the ecological engineering. Average total nitrogen (TN) and total phosphorus (TP) concentrations in the surface sediments were 7043 and 1370 mg kg −1, respectively, in May 2005, while after 1 year, TN concentration was reduced to 2929 mg kg −1 and TP concentration was reduced to 352 mg kg −1. We conclude that ecological engineering can lower the nutrient content in surface sediments when it is used to improve water quality.