Abstract:

Urbanization is an important symbol of the economy development,and one of the most significant economic and social phenomena of the contemporary era,but it brings a serious crisis of resources and ecological problems.Poyang Lake is the largest freshwater lake in China and an important wetland for birds in the world.Poyang Lake basin was chosen as the typical studied area; urban population was used to examine the urbanization process,1990-2011 Jiangxi Statistical Yearbook data was analyzed in this paper.The influences on ecosystems caused by urbanization in Poyang Lake basin were discussed,including land use pattern changes,water resources variation,wetland ecosystems biodiversity and other resources depletion,air and water pollution problems.The results showed that urbanization progress of Poyang Lake basin cities and its mechanism were different.Nanchang,Jiujiang and Shangrao had rapid urban expansion,and the development of Jingdezhen and Ganzhou was more gentle. Urbanization led to increasing scarcity of water resources,revolutionized the land surface,undermining the region of normal water cycle.Annual rainfall declined,but the total annual water consumption in the cities showed an increasing trend after 2003; the yearly agricultural water increased,but industrial water consumption changes were different in each city.Biological diversity was seriously threatened by urbanization.Lake water area and wetland area were continued to decrease,the composition and structure of the biological environment changed a lot. The rapid expansion of urbanization and lack of green infrastructure put enormous pressure on the ecosystem of Poyang Lake basin,especially on air pollution and water pollution.Industrial gas emissions of Jiujiang city increased,the industrial wastewater of Nanchang and other cities was pretty high,which caused the lakes environmental degradation.Finally,according to the analysis,appropriate countermeasures were proposed to deal with these problems,such as coordinating development between land use intensification and biodiversity conservation;utilizing water resources in a reasonable manner;strengthening water conservation,especially to strengthen industrial and agricultural water conservation;optimizing the controlling schedule scheme of the Three Gorges reservoir operation and the “five rivers” ecological water conservancy project; building the natural buffer zone and continuous habitats in the process of urbanization in order to save and restore biodiversity around the city; accelerating the construction of urban sewage treatment plants and landfill,controlling nonpoint source pollution; improving the ecological environment protection responsibility of citizens through education.In the early stage of Poyang Lake basin urbanization development,this research provides theoretical references for ecological urban construction of Poyang Lake economic zones,and harmonizes the urbanization and ecosystem sustainable development