1986—2015年滇西北地区土地利用类型时空动态研究

Temporal and Spatial Dynamics of the Land-use Types in the Northwest Yunnan from 1986 to 2015

基于1986年、1995年、2005年3期土地利用数据和2015年的Landsat 8 OLI数据,利用土地利用类型结构变化、分形理论和景观格局指数,分析滇西北地区30 a来土地利用类型的时空变化特征。结果表明:1986—2015年研究区土地利用均是林地占绝对优势,其比例均在64%以上,城乡工矿用地面积最小,面积比例均不足1%,水域除外,其他土地利用类型动态度均呈上升趋势,城乡工矿用地变化最大;土地利用类型转换主要存在于林地—草地—耕地三者之间,2005—2015年间,三者间转换面积达到最大;各土地利用类型分形特征表现为林地、草地、城乡居住工矿用地和未利用土地的斑块形状趋于稳定,而耕地和水域趋于活跃状态;研究区各土地利用类型变化较复杂,景观总体破碎化加剧,连通度增强。

The land use data of 1986, 1995 and 2005, and 2015’s Landsat OLI data in the Northwest Yunnan region were used to analyze changes in land-use type of the study area in the recent 30 years through dynamics in the land-use types, fractal theory, and landscape pattern indexes. The results showed that the woodland always dominated the study area from 1986 to 2015, whose percentages was more than 64% of total study area, and the urban land was always increasing though its area was less than 1%, the dynamic indexes of other land-use types were mostly increasing, and the changes of urban-land area was fastest;the major area-transformation among land-use types was in woodland, grassland and cropland, the number of transformation reached its maximum in the decade of 2005-2015;The fractal feature of land types for the study area was obvious, the woodland, grassland, urban-land and unutilized-land tended to relative stabilization, while cropland, and water was tended to active. The fragmentation of overall land landscape was increased, and each land-use type was tended to be aggregated.