The Study On Evaluation Of Wetland Eco-environmental Quality Of Northern Suburb Of Zhangye Based On GIS And RS

Heihe is the second largest inland river in China with plenty of water,which is928km and flows through the territory of Zhangye299km.Thousand of years, Heihe forms a large area of river wetland, Lake Wetland and Swamp wetland in the western in our country in the desert regions of Zhangye,which plays an important role in conserving water,improving the regional climate, preventing soil erosion and resist sandstorms,and it is the lifeblood of the west region in ecological security and sustainable economic and social development.However,Heihe basin area of wetland is down sharply,biodiversity is damaged,wetland ecological deterioration of the environment, ecological service function drops,which is a significant regional ecological security threat because of the global climate changes and unreasonable human activities since the1960s.Faced with such a serious situation,the goverment of Zhangye carried out a series of measures to protect the wetland, such as " Gansu middle reaches of the Heihe River wetland restoration and control engineering"," Zhangye ADB loan Gansu (Zhangye) city infrastructure construction and wetland protection project",which can promote the regional ecological environment,during2009to2011Year.This paper selects Zhangye Beijiao Wetland Nature Reserve in the protection,restoration of typical area as the study area, the wetland ecological environment quality assessment research to understand the regional ecological environment quality changes.This article choosed the northern suburb wetland in Zhangye which is the nature reserve protection and recovery management typical area as the study area. It based on the wetland ecological environmental quality assessment of research to reflect the change of ecological environment quality of wetland.This article firstly introduced the theories and methods related to wetland ecological environment quality assessment, including the definition of wetlands, wetland ecological environment quality evaluation of research progress, RS> GIS in wetland ecological environment quality assessment applications, etc. which is the basis of this study. Secondly, it introduced the principles and methods of eco-environmental quality Index System. Combining the ecological environment characteristics to wetland in the suburb of Zhangye northern, it used the" pressure state response"(PSR) model to establish a set of Index system, which is founded by the United Nations Organization for economic cooperation and development (OCED).The index system includs pressure index,wetlands status indicators and response index of Zhangye Beijiao wetland ecological environment quality. Finally, it used geographic information system (GIS) and remote sensing (RS) technology to extrct wetland information, and completed the wetland ecological environmental quality assessment.By selecting the data of in2009and2011,the article analysised and evaluated changes of the environment quality of northern wetland of Zhangye, before and after the implementation of the wetland protection and restoration project.The results plays a better role in guiding finding the effects and the weak of the wetland protection in recent years.And last it puts forward some proposals and countermeasures,in order to provide reference and guide to the protection of wetland for governments.