Spatail Recognition Of The Minimum Ecological Land Based On GIS In Yanji-longjing-tumen Area

The quantity of cities and urban population in the world are increasing quickly due to the developing of economy,that make the scale of urban land expanding gradually and demand more and more cities invading to the space of nature.The ecological environment is destroying seriously accompanied with the ecological land is dieing away.Facing to the contradiction between developing urban economy and protecting ecological environment,we should know where the ecological land baseline is and allocate the ecological land in a high effect way.Only in this way can we guide the city planning and city constructing effectively and provide a fine base for the city's sustainable developing.Based on the ecological environment in Yanji-Longjing-Tumen area,this paper first carries on the landscape component,ecological system function and landscape pattern and analysis of the comprehensive evaluation of ecological land in Yanji-Longjing-Tumen area.The paper identifies the minmum ecollogical land in Yanji-Longjing-Tumen area,point out existing problems and propose the future development plan.The main research contents are as follows.(1)Combining with the characteristics of the Yanji-Longjing-Tumen Area,to realize the purpose and significance of the study,meanwhile to detailed analysis the ideology of "centralization and decentralization" which is presented by professor Forman.Then,establishing the index evaluation system of the study.(2)Selecting type of land use,water conservation,biodiversity conservation,seeds plaque and other three indexs from landscape component,landscape ecological function and landscape pattern which is used to generate the thematic maps.At last,to generate the thematic map that shows the comprehensive evaluation of ecological land of the Yanji-Longjing-Tumen area.The map assignments 1?5 level,the five levels corresponding to very low,low,medium,high and very high.(3)According to the score of the comprehensive evaluation of ecological land,to extract the ecological land that occupied the total area of 30%,40%,50%and 60%from low to high.According to the ideology of "centralization and decentralization" and comparing with other cities we establish that 60%is the threshold value of minimum ecollogical land in Yanji-Longjing-Tumen area.The forest land occupy 91.64%of total minimum ecollogical land.Next,the farmland and wet respectively occupy 6.01%and 1.01%.There are a few garden plot and green land.Finally,according to the distribution of the minimum ecollogical land throw out some suggestions about how to protect the ecological land.This paper used the landscape security pattern to study the protection of the ecological land,which not only provided a new case for the study of ecological land protection in china,but also provided he theoretical basis,data support and scientific basis for the ecological planning of land use of Yanji-Longjing-Tumen area.It is conducive to maintaining the ecological security of the study area,and it played a positive role in promoting the construction of the Yanbian Korean autonomous prefecture being a national ecological civilization advance demonstration zone and the Yanji-Longjing-Tumen area being a leading area of green transition development.