2000—2014年抚仙湖流域土地利用动态变化研究

Dynamic Change of Land Use in Fuxian Lake Basin from 2000 to 2014

笔者以抚仙湖流域为研究区域,根据2000—2014年土地利用现状数据及2000、2014年2期影像资料,运用GIS空间分析技术和数理统计法从土地利用变化幅度、土地利用动态度、转移方向及景观格局4个方面系统分析研究区15年来土地利用时空变化特征。结果表明:(1)研究区主要土地利用类型为耕地、林地、水域和未利用土地。除水域外,其余各类土地面积均发生了较大变化,未利用土地不断减少,耕地先减少后增加,其余5种地类逐年增加。各乡镇土地利用综合动态度在0.75%~7.64%之间,总体呈现流域北部大于流域南部,湖滨区大于山区的特征。(2)研究区土地利用转换类型有23种,面积共18834.33 hm^2,占流域总面积的12.15%。土地利用变化集中于未利用土地、耕地、林地、城镇村庄及工矿用地、交通用地五者之间的相互转换,主要位于青龙镇和龙街镇。(3)研究区景观破碎指数、多样性指数、均匀度指数呈上升趋势,优势度指数呈下降趋势,土地各利用类型面积更趋于平均化和多样化。人类活动对土地利用格局的形成影响强烈,人口增加、经济发展和城市化是研究区土地利用变化的主要原因。

Based on the land use data from 2000 to 2014 and the remote sensing data of TM images in 2000 and 2014, the authors used GIS technology and mathematical statistics method to analyze the spatial-temporalvariation of land use in Fuxian Lake basin from land use change amplitude, land use dynamic degree, thedirection of land use transformation and landscape structure. The results show that：（1） the major land use typeswere arable land, forest land, water land and unused land; in addition to water land, the other land use typesgreatly changed, the areas of unused land decreased, the arable land reduced at first and then expanded, whileother land types continued to increase; the integrated dynamic degree of land use in each township wasbetween 0.75% and 7.64%, which appeared to be higher in the north than that in the south, and higher in thelake district than that in the mountain area;（2） there were 23 types of land use conversion in this region, withthe total area of 18834.33 hm^2, which accounted for 12.15% of the study area; land use change was mainly theconversion among unused land, arable land, forest land, residential and industrial land and traffic land, theconversion land mostly located in Qinglong and Longjie;（3） the landscape fragmentation index, diversity index,evenness index of the study area all increased, while the dominance index was in a downward trend, the area ofeach land use type tended to be more average and diversified. Human activities had strong influence on theformation of land use pattern, the population growth, economic development and urbanization were the main driving forces.