Study On Dynamic Change Of Landscape Pattern In Gannan Rare Earth Mining Area By Remote Sensing

As an important mineral resource,rare earth has made great contribution to the development of national economy.However,along with the economic development,the rare earth mining area has many ecological and environmental problems: soil erosion,landslides,water pollution,farmland destruction and so on.Taojiang River is a major tributary of the Ganjiang River.The upper reaches of Taojiang River flow through some important rare earth mines in Ganzhou City.The watershed area includes the major rivers such as Otto River,Lianjiang River,Longjing River and Donghe River.It is a hot topic to study the eco-environmental changes qualitatively and quantitatively in view of the various technical methods in different areas.Remote sensing,as a means of monitoring the change of landforms,has been widely used in the monitoring of land in mining areas.The landscape pattern can be derived from the interaction between nature,biology and social environment of ecological environment in different scales.result.Therefore,the combination of remote sensing technology and landscape pattern analysis can be used to analyze the change of landscape pattern in rare earth mining area,which provides a new idea for ecological environment protection.Based on TM data and ENVI5.0,Arcgis10.2 and fragstats4.2 software,this paper firstly interprets the image of the upper reaches of Taojiang River,and then makes a classification map of the landscape information of the study area.Land use change and landscape pattern index in the study area.Finally,the landscape pattern of the individual small watershed in 2016 was analyzed and compared,and the following conclusions were drawn:1.In this paper,the spectral information of remote sensing image is considered synthetically.Firstly,the classification system of the study area is established,and then the multi-source data(normalized vegetation index data,elevation data)are used to calculate the classification of the remote sensing images.Data,etc.),the use of decision tree classification method to establish Gannan rare earth mining area classification map,to improve the accuracy of classification purposes.2.The land use change of the study area was found to be the biggest change,which was mainly transformed into cultivated land and urban land.The urban land increased fastest.From 2000 to 2009,the area of mining area showed an increasing trend.Increase by the reduction of the line changes.3.The landscape pattern of the study area was analyzed,and the landscape pattern index of the upper reaches of Taojiang River was studied from the category level and the landscape level respectively.Forest land,as the dominant landscape elements in the basin,plays an important role in the landscape ecological balance of the whole basin.The economic activities of human beings,the rapid development of urbanization and the destruction of mining environment have resulted in the fragmentation of land types,which has destroyed the ecological stability to a certain extent.4.The comparison of the landscape pattern in the watershed shows that there are some differences in the patch types of landscape elements in different watersheds,but the landscape indices are similar among different watersheds.The ecological landscape of each river basin is in a stable level.