Abstract: The lake field in the East Taihu Lake had been rapidly cultivated in the Qing Dynasty. Together with the mountain soil erosion, the sediment and water vegetation in the East Taihu Lake were increasing，and both the silt and the lake field were expanding. The East lake field cultivation blocked the water flow out of Tai Lake，causing the Wusong River shift northward to the Guajing-Kou. This helped to the rapid development of the lake field in the Northeast of the Tai Lake. Small dikes set up in this cultivation movement gradually made up the new river networks in the field, ideal for growing mulberry and rice. The mulberry and silk industry provided the fertility for the rice paddy soil, eventually forming an ecologically sustainable agriculture pattern that is traditional to the Jiangnan area．