The Study On Evaluation Of Yangzhou Urban Ecological Environmental Quality Based On Principal Component Analysis

Urban ecological environmental quality is not only related to the stability of the urban ecological function, but also affect the sustainable development of cities.During the twelfth five-year plan period, Jiang Su province has been entering into a critical period of promoting the construction of ecological province and raising the overall level of ecological civilization.And people give more and more attention to the ecological environmental quality assessment. Although theorists exist a lot of research for ecological environmental quality assessment, they still have problems in terms of process of assessment,especially in the respects of constructing index system and selecting evaluation method.In order to study the changing trends of urban ecological environmental quality and further improve the evaluation methodology, the paper takes Yangzhou as research object and constructs its index system of urban ecological environmental quality assessment from the perspectives of nature, economy and society on the basis of other related index systems and ecological theory of social-economic-natural complex ecosystem of Ma shijun. The paper gives weight indicators with entropy method which can reduce subjectivity.Through weight value,we can get different and rich information which will provide reference for ecological construction and protection of Yangzhou. In the selection of evaluation method,the paper respectively use fuzzy comprehensive evaluation method and principal component analysis method,at the same time, the author makes certain improvements of data preprocessing, principal component rotation,calculation of the composite score value and so on.Then according to the evaluation result, we use regression equation to analog variable based on economic development and pollutant emission,environmental protection investment and pollution control, population and arable land with SPSS19.0.By comparing the two evaluation methods,we find that the result we get from principal component analysis method roughly keep in pace with that get from fuzzy comprehensive evaluation method in terms of longitudinal Changing trends,which indicate that principal component analysis method used in the field of ecological environmental quality assessment is scientific and reasonable.Generally speaking,the urban ecological environmental quality of Yangzhou from2000to2010is on the rise,and it’s under the benign development.Development course is roughly divided into two stages:From2000to2005, urban ecological environmental quality of Yangzhou is not ideal, because ecological construction of yangzhou is in early stage and ecological environmental quality is generally below the average;From2006to2010, urban ecological environmental quality of Yangzhou is good, because ecological construction of yangzhou is in the stage of development and ecological environmental quality is generally above the average.