Tai-lake region lyinn on the Yangtze and Qiantang delta at the juncture of north and central subtropics is an independent agro-ecological region. Through thousands years of human activities of agricultural practice, this region started from its ecological stage of soil swamping, through the stages of polder farming, cropping of rice and wheat, to a stage of coexisted multiple systems of agriculture, forestry, fishery and sericulture. A well efficient and functional agro-ecological system with stable stricture, high resistibility to natural calamities has been formed, which leads to the region being developed to be,one of the most notable integrated agricultural bases in China.In recent years, triple cropping system. has been adopted extensively regardless of the local conditions, which results in deterioration of soil environment and its fertility. In order to improve this situatiop, it is necessary to study agno-ecological regionalization of this region.