Study On Regional Ecological Service Value Based On Land Use Change

Land use and ecosystem services are interdependent and constrained.Ecosystem services change with the change of land use structure and function.This study takes the Lengshuitan District in southwestern Hunan as the research object,based on a 0.5km×0.5km grid,spatial analysis of land use change and ecosystem service value are conducted.In theory,the standard deviation ellipse method is used to analyze the spatial change of ecological service value,and the spatial analysis method of ecological service value is expanded.In practice,it provides a reference for guiding the rational use of land,optimizing the structure of land use,and promoting the sustainable development of economy,society and ecology.Based on land use vector datas in 2005,2009,and 2014,the study analyzed the spatial pattern of land use change and ecosystem service value,and the correlation between land use change and ecosystem service value.In this study,land use change is analyzed by land use dynamic index and land use level index.The equivalent factor method is used to calculate the value of land ecological services.In order to further expand the spatial analysis method of ecological service value,the spatial standard deviation ellipse is introduced on the grid unit of 0.5 km×0.5 km with the support of ArcGIS10.2 to analyze the spatial characteristics and spatial differences of land use and ecological service value.Finally,the grey correlation method was used to analyze the impact of land change on ecological services value,the Person correlation coefficient is used to analysis the correlation between land use level and ecological service value.The conclusions are as follows:(1)During the study period,the single dynamic degree of land use in Lengshuitan District changed the most.From 2005 to 2014,the absolute value of land use dynamics was ranked as:garden>bare land>construction land>dry land>grassland>paddy field>forest land>water area From 2005 to 2014,the comprehensive dynamic degree of land use in the Shanhu Township was the largest,and the comprehensive dynamic degree of land use in the urban area was the smallest.In the three periods,the land use degree index in the whole area was increased firstly then decreased.In the three periods,the number of low and medium-value land use grids continued to decrease,and the number of grids with high and extremely high values continued to increase,it shows that the level of land use has been continuously increasing over time.According to the standard deviation ellipse method analysis results,during the study period,the standard deviation ellipse center of gravity of land use is located in the Gedidang Village of Gaoxi Township,and the degree of land use mainly occurs in the northwest-southeast direction,the degree of land use standard deviation in each township was changing little in the ellipse direction and aggregation degree.(2)In 2005,2009 and 2014,the total value of ecological services in the region first increased slightly and then decreased.Based on the analysis of the number of grids in the four levels of ecological service value,it can be seen that low-valued grids of land ecosystem service values were increasing.The reduction of the extremely high value grids was indicated that the value of ecosystem service in the region has declined.According to the analysis results of the standard deviation ellipse method,in 2005,2009,and 2014,the value of the ecological service in the entire region was located in the Gedidang Village of Gaoxi Town,and the ecosystem service value was basically concentrated along the northwest-southeast direction.The overall trend firstly expanded and then contracted.During the study period,the standard deviation ellipse parameters of each township fluctuated less.(3)The order of relevance of land use structure and ecological service value isforest land>water area>paddy field>dry land>grassland>construction land>bare land>garden.The higher degree of land use level is in the whole district and townships,the lower the ecosystem service value is.During the study period,the center of land use and the value of ecological services in the entire region were located in the township of Gaoxi.The ratio of long-short axis and azimuth of land use degree and ecological service value of each township showed a one-way linear relationship.The elliptic parameters of the ecological service value of the whole district and each township were changing with the elliptic parameter of the land use degree.