Abstract:

 Assessment of ecological quality is central to environmental management but at present little consensus exists on what it constitutes Increasing recognition of the validity of including human values as part of our understanding of ecological quality has arisen with the concept of ecosystem services，ie the benefits people obtain from ecosystems，as a means of valuing ecosystems As the largest and most modern city，Shanghai has experienced extensive urban expansion and urbanization since Chinas economic reform in the late 1970s In the process of urbanization，natural vegetation cover is largely replaced by paved surfaces，and open spaces are maintained for recreational or ornamental purposes，so that the ecosystem dynamics of the remaining green areas of the city are usually quite different from those of the open countryside Changes in vegetation imply changes in the physical properties of land surface，including surface albedo，surface roughness，leafarea index，rooting depth，and availability of soil moisture The resulting ecological consequences of urban sprawl have caused considerable concern among scientists and policy makers To date，however，spatially explicit monitoring of the urbanization together with comprehensive studies of the ecological consequences of human settlements in the entire Shanghai area has not been conducted Based on the climate data from 11 meteorological stations，land use data derived from satellite remote sensing，and damage data from meteorological disaster and vegetation leaf area index data，the assessment index system of urban ecological quality for human settlements was built using analytic hierarchy process and Delphi technique. The assessment and regionalization of ecological quality of human settlements was completed at 250 m spatial grid from humidity index，meteorological disaster index，water body density index，vegetation coverage index and vegetation quality index with the help of remote sensing and geographic information system technique The results indicate that the assessment index system is suitable for the assessment of ecological quality of human settlements in Shanghai，and in recent years，the integrated ecological quality of human settlements is good or fair in most of Shanghai In some parts of Minhang，Baoshan and Jiading and several parts of Qingpu and Pudong，the ecological quality of human settlements is poor This is related with the more areas of industrial or construction land，more meteorological disasters and lower vegetation cover and vegetation quality in these regions In some parts of Northern and Southern Chongming and several parts of Pudong，Nanhui and Fengxian，the ecological quality of human settlements is excellent This is attributed to the higher humidity index，water bodies density index， vegetation coverage index and vegetation quality in these regions As the third largest island in China and the largest alluvial island in the world，Chongming is declared as an ecological island by the Shanghai Government and all development activities that conflict with the protection of the environment will be prohibited，so in most parts of Chongming the ecological quality of human settlements is good or excellent Despite its major economic development，Shanghai has also seen severe ecological problems in recent years Managing the tradeoffs between urbanization and ecological protection will be a major challenge for local policy makers.