Abstract:

Abstract:Ecological environment is a very important problem in controlling continuous economic development in the world. Changsha, as a developed and populous metropolis, has witnessed a fast advance in economics and a great change in city construction. The strong needs of land will surely make huge impact on the intension，mode，scale，distribution of land use, bring strong impact to the ecosystem environment, and threat ecosystem safety seriously. This paper expounds the concept of urban land ecological risk assessment, accounts for the urban land ecological risk. The thesis analyses the eco-environment current situation，identifying some ecological environment problems related to land use. By utilizing principal component analysis and K-means clustering, a model for urban land ecological risk assessment is proposed, and then the paper analyses and evaluates the ecological risk, and studies how to deal with it. The research results are as follows:(1)Changsha city urban land ecologically use risk level has wholly been rising from 1996-2006, the evalue of risk is -0.85286(Ⅴ)in 1996，whereas the value of 2006 is 1.321039(Ⅰ),corresponding to a declining in 2000-2002 and a decrease in 1996-1999, 2003-2006;(2) the conclusion signifies that Changsha city land utility isn’t in accordance with eco-environment amelioration, therefore ,it is also necessary to adopt a series of countermeasures to coordinate the relations between Changsha’s land use and ecological environment, promote the sustainable development of land use and ecological environment.