Analysis And Evaluation Of Ecological Sensitivity Of Land Use In Mayang County

The change of land use patterns will not only cause the environmental change of land ecosystem,but also affect the sensitivity of land ecological.It is of great significance to carry out the analysis and evaluation of ecological sensitivity based on land use to promote the sustainable use of regional land resources and ecological construction.Taking Mayang County of Hunan province as the research object,this thesis explores the characteristics of land use in 2006 and 2015 as well as its dynamic characteristics in the last decade.Besides,this research constructs the index system of ecological sensitivity to the land use,and scientifically selects six factors(Land use types,slope,elevation,geological hazards,human activities,vegetation coverage)that highlight the regional characteristics of Mayang's mountainous area.The expert scoring method and analytic hierarchy process(AHP)were used to determine the grading standards and index weights.By aid of the technical platforms of MapGIS67,ArcGIS10.2,ENVI4.8,the ecological sensitivity of land use in Mayang County has been evaluated.Finally,we have proposed some protection suggestions for the area with all kinds of sensitivities.Main conclusions are made as follows:From the perspective of land use ecological sensitivity,the variation ranges of different types of land use are not consistent from 2006 to 2015.The area of farmland,forestland,other agricultural land and natural reserve had a constant decline.Also,the dynamic degree of land use showed negative growth,respectively-0.47%,-1.95%,-4.86%,-4.15%;To the contrary,the area of garden plot,construction land and water area increased and the dynamic degree of these land use reached 57.89%,1.80%,0.15% respectively.During the past decade,the comprehensive index of land use in Mayang County changed from 225.26 in 2006 to243.01 in 2015 with the increased rate of 7.31%.Therefore,the land-usedegree of Mayang County is comparatively high.In the respect of land use conversion,there are four points.(1)The insensitive area has the minimum coverage,which is 6058.79 hectares,accounting for only 3.87 %of the total area of the county.As its ecosystem has high stability,this area is positioned as a key development zone and is prepared for all kinds of developments and constructions based on socio-economic development needs.(2)The distribution area of comprehensive area with low ecological sensitivity is 39937.90 hectares,which covers 25.51% of the total area.It belongs to the sensitive transition zone with comparative low ecological pressure,and is suitable to be classified as a prior development zone,developing the new industrialization and green agriculture industrialization with the comprehensive survey of geological structure,the premise to avoid soil erosion and flood prone areas.(3)The area with moderate ecological sensitivity has the most extensive distribution and the largest area.It takes 39.73% of the total area with 62200.43 hectares.This area should be positioned as a restricted development zone.After a detailed feasibility study,it can be developed and utilized appropriately.And the environment-friendly industries such as eco-agriculture,tourism agriculture should be given the developmental priority.(4)The area with high ecological sensitivity is an important ecological protection area,which has the coverage of 48360.77 hectares and takes up 30.89% of the total area.This area has low environmental capacity and high sensitivity to the interference of human activities.It is suggested that this area should be indentified as a prohibited zone and maintain the integrity and consistency of the native ecosystem.