Analysis Of Spatial And Temporal Evolution Of Land Use And Landscape Ecological Security Pattern In Qiannan Buyi And Miao Autonomous Prefecture

Right land use is significant to the development of regional economy,improvement of people's living standard and quality of life.With the implementation of the West Development Strategy of Chinese National Economy,the economy in western region,especially in the minority areas,has developed rapidly.However,there are many problems faced like low land use efficiency and environment damage.The Qiannan Buyi Autonomous Prefecture(Qiannan Prefecture),which is located in the transitional zone between Guizhou Plateau and Guangxi hilly,has maintained the sustainability of natural resources and environmental ecology.In 2011,comrade Xi Jinping in Guizhou Province,guiding County inspection,proposed "green mountains and rivers are the Jinshan Yinshan in higher level" as important instructions the first time.The remote sensing image data of Landsat TM,Landsat 7 ETM/Landsat 8 in 1995,2000,2005,2010 and 2015 in Qiannan Buyi and Miao Autonomous Prefecture were used in combination with DEM,forestry maps and related statistical data by ENVI5.1,ArcGIS 10.2,Fragstats4.2,SPSS20 and other software tools.The points analyzed are as follows:(1)The change of land use type and landscape pattern indexes were analyzed from 1995 to 2015 to understand the evolution of land use pattern.Principal component analysis and Pearson correlation analysis was used to get the driving factors of land use change.The results of landscape metrics show that the forest land is the main land use type and the area is decreasing from 1995 to 2015.The area of cultivated land,grass,water and construction land is increasing.Land use pattern shows a trend of decentralization and patches show a trend of fragmentation and complication for its shape.The diversity of landscape is increasing.According to class metrics,the forest shows a trend of decentralization,fragmentation and diversity for patch shape.For the change of landscape pattern,there are differences among counties,among west areas and east areas.The main driving factors of land use change in 20 years are temperature change,natural disaster and population change.(2)The spatial distribution pattern of the ethnic villages and the landscape index of the different scale buffers from 1995 to 2015 were analyzed to understand the changes of the land use pattern around the local ethnic villages.The results show a trend of low slope,low altitude and a unique pattern.In the 3km buffer area,the patches show a trend of fragmentation and centralization.In the 6km buffer area,the patches show a trend of fragmentation and decentralization.(3)Village expansion resistance in 2015 was analyzed by using the minimum accumulation of resistance model.On this basis,the landscape ecological security pattern and spatial correlation of Qiannan Prefecture in 2015 was discussed.The results show that the ecological protection area around the buffer area of the ethnic villages has a certain degree of obstruction to the development of the village.The expansion resistance is negatively correlated with the ecological resistance.Besides,the landscape ecological security pattern of Qiannan Prefecture in 2015 was of densely distributed and highly correlated with the space.It was descended from southwest to northeast.