Land Use Change And Ecological Status Evaluation In Chaohu Basin

Land cover / use change is an important factor of global environmental change.Therefore,the study of global environmental change can be used as a research tool through land use research.At present,with the emergence and development of remote sensing technology,remote sensing data sources become more and more rich,every kind of remote sensing image for extracting land cover provides opportunities for development,the new information at present,remote sensing has become the acquisition of land cover information is one of the important ways.With the decline of land quality,water pollution,shortage of water resources,species become increasingly scarce,global warming and many other environmental problems,people began to realize that the human activities have an important impact on the global environment,watershed as a special ecological system,the basic situation of the ecological situation it can reflect the ecosystem service function area the important ecological status of ecological function area evaluation can provide scientific basis for government decision-making,policy formulation,is conducive to the sustainable development of social economy.This paper takes Anhui Province in central Chaohu basin as the research area,remote sensing and GIS based on the principle of remote sensing data in 1990 and 2000,the download area in 2005,2010 and 2015(TM/ETM/HJ-CCD),the interactive interpretation using object oriented classification method,the study area was divided into different types of land use,and the change of 25 years to do the test,understand the change and distribution of the whole Chaohu River basin.On this basis,a series of analysis is made on land use change,dynamic change and landscape pattern change.By selecting appropriate index,we can evaluate the ecological status of Chaohu River Basin and provide some protection suggestions.Research shows:(1)The change of land use types in the Chaohu basin was obvious in the last 1990-2015 years,and the transformation between the types of land was obvious.The most important is to reduce the amount of artificial surface increased greatly and the cultivated land,mainly for the rapid development of city,city construction land and road construction,artificial surface into mostly from cultivated land;cultivated land,most turned artificial surface,partially converted into woodland,part to wetlands,protect the environment is the eternal theme,so start on farmland planting,the original into woodland;also the wetland area decrease,mainly to a small amount of arable land,to the artificial surface.(2)The landscape index of 1990-2015 years in the Chaohu River watershed land use structure of land use index of patch level landscape pattern of 1990-2015 years,the surface of the artificial landscape polymerization does not stop in space,a small area of the plaque with artificial surface to eliminate,reduce the degree of landscape fragmentation.In addition,the artificial surface and cultivated land have absolute advantages,and occupy the most proportion in the whole landscape,and the dominant position is more prominent.From 1990 to 2015,the artificial surface and cultivated land types become more concentrated.(3)The ecological status of Chaohu basin area in 1990,2000,2005,2010 and 2015 is not ideal.Except for Mount Holyoke and Yuexi counties,the ecological condition is superior,the other districts and counties are poor,indicating that the ecological system of the Chaohu basin is weak and the ecological function is not stable,and the ecological condition index is held from 1990 to 2015.The decline indicates that the land cover change caused by human activities has caused great disturbance to the ecological environment.The ecological construction of Chaohu basin is imperative.