By the end of May in 2007，blue algae pollution broke out in Taihu drainage area，which was noted for prolific production of primary products.This event revealed that water pollution in Taihu watershed area had almost researched the critical point.Hence，it aroused intensive public doubt on the economic developmental pattern of the South-Jiangsu area.And now，the South-Jiangsu area is adopting various measures to solve the pollution of Taihu through implementing the most rigorous policies，and they are also seeking for new problem solving measures such as Trade on Pollution-Discharge Right.