Study Of Ecosystem Quality Evaluation In Shanghai City

It gradually attracted people’s attention that the development of urbanization caused land-use:hanges and ecosystem changes. Social and economic activities of human beings had a great mpact on the structure and function of ecosystem. According to the ecology principle and method of system science, how to evaluate the evolution characteristics of ecosystem quality has become one of the most important and fundamental issues which harmonize he relationship between city development and ecological protection.Based on RS and GIS echniques, this paper analyzed the dynamic changes of ecological system, Shanghai city was aken as research object. An assessment model of ecosystem quality was designed in this paper pased on ecosystem structure, function and stress, to study the dynamics changes, spatial difference and influencing factors of ecosystem quality in2000-2010.The main research conclusions are as follows:(1) Since2000, with urbanization development, great changes have taken place in the ecosystem-types in Shanghai city. In ten years, urban land increased by a big margin and substantially, with an average annual growth rate of95.73km2. The most obvious increase district was Fengxian.Forest land area accounted for small proportion, but had some growth.Chongming County had the most area of forest land and the largest increase in all districts with118.19km2increased; wetland showed a fluctuation change with increased first and then decreased, but the general trend was up in10years. Chongming County also had the most area of wetland and the largest increase in all districts.The cultivated land always accounted for higher proportion in the ecosystem of Shanghai.But for greatly influenced by human-caused, it reduced111.83km2area every year.And Pudong District showed the maximum decrease by215.76km2in ten years.(2) In the evaluation of ecosystem quality of single factors, Chongming County and central urban district had the highest indexes of ecosystem structure, and the general trend was upward.Chongming County had the highest indexes of ecosystem function.There are1434300 tons of biomass and3045000tons of net primary productivity in2010.Central urban district was the lowest,only had10600tons of biomass and76000tons of net primary productivity.Ecosystem quality was significantly influenced by urbanization,which is the most important factor of stress.Chongming County was under least stress of urbanization, and central urban district was heavily urbanized.(3) In the comprehensive evaluation of ecosystem quality,from the spatial and temporal variation,Chongming County was the best quality region in Shanghai, as its ecosystem quality indexes were at optimum level in the three stages. Followed by Pudong and Jinshan District, their level declined from fine in2000to general in2010and2005respectively. The ecosystem quality of central urban district was the worst. The changes of ecosystem quality are——Jinshan, Fengxian and Songjiang District turned worse significantly, Pudong District become down obviously, Jiading District had a slight variation, and the other districts hadn’t changed much.The research provided a method of ecosystem quality assessment. The results showed the dynamics changes of Shanghai ecosystem quality in2000-2010. It can provide reference frame for ecosystem management.