1980—2020年青藏高原土地利用变化强度及稳定性分析

Analysis on Change in Intensity of Land Use and Stability on the Tibetan Plateau from Year 1980 to 2020

土地是人类社会和生态环境之间的重要纽带,对土地利用变化进行深入分析,能够为土地资源管理和可持续发展提供科学依据。运用青藏高原1980年、1990年、2000年、2010年和2020年5期的土地利用数据,采用土地利用转移矩阵方法,从间隔层次、地类层次和转移层次3个方面对1980—2020年青藏高原土地利用变化强度及稳定性进行分析。结果表明:(1)1980—1990年青藏高原土地利用变化强度较大,1990—2000年、2000—2010年两个时期变化强度减缓,2010—2020年又开始快速变化。(2)1980—1990年和1990—2000年,城乡用地、耕地、草地变化活跃,未利用土地和林地的变化比较稳定;2000—2010年,土地利用总体变化比较稳定,其中城乡用地、耕地和沼泽地变化比较活跃;2010—2020年总体土地利用变化强度增加,其中城乡用地、耕地和草地变化最为活跃。(3)1980—2020年4个时间段内,中覆盖度草地向低覆盖度草地的转变强度、高覆盖度草地向耕地和沼泽地以及中覆盖度草地转变强度都呈现出一种稳定的倾向性系统模式;中、高覆盖度草地向城乡用地的转变强度和林地向低覆盖度草地转变强度的过程都表现出稳定的避免性系统转换模式。

Land is an important link between human society and ecological environment.The analysis on the changes in land use can provide a scientific baseline for land resource management and sustainable develop-ment.The changes in the intensity of land use and stability on the Tibetan Plateau from year 1980 to 2020 were analyzed in interval level,land type level and transfer level with using the transfer matrix method based on the land use data on the Tibetan Plateau for year 1980,1990,2000,2010 and 2020.The changes in the intensity of land use was relatively high in the period of year from 1980 to 1990,but it decreased in periods of year from 1990 to 2000 and from 2000 to 2010,and it increased again in period of year from 2010 to 2020 on the Tibetan Plateau.The change of urban and rural land,arable land,and grassland were more active in the periods of year 1980 to 1990 and 1990 to 2000,but the unused land and forest land was relatively stable.The change of the over-all land use was relatively stable during the year 2000 to 2010,however urban and rural land,arable land and swampy land changed actively.The change in the overall intensity land use increased during the year 2010 to 2020,while the land use intensity of urban and rural land,arable land and grassland changed most actively.The intensity of transition from medium-coverage grassland to low coverage grassland,and the intensity of transforma-tion of high-coverage grassland to cropland and to marshland and to medium-coverage grassland showed a sta-ble tendentious system pattern in four time intervals from year 1980 to 2020.While the intensity of transition from medium and high-coverage grassland to urban and rural land,and the forest land to low-coverage grassland showed a stable avoidance system transformation pattern in four time intervals from year 1980 to 2020.