柴达木盆地土地利用/覆被综合指数评价

Evaluation of land use/cover change and land use grade in Qaidam basin, China

基于欧洲空间局气候变化项目土地覆被产品(ESA-CCI-LC)的柴达木盆地2000、2005、2010、2015年四期土地利用/覆被数据,计算其时空变化的转移矩阵和转移方向,提出土地开发利用等级指数。结果表明:柴达木盆地主要土地利用类型为草地和未利用地,面积占比为51.6%和44.9%,水域、耕地和林地占比依次减小,居民用地占比最小;研究期内耕地、草地和居民用地持续增加,未利用地持续减少,草地和未利用地之间相互转化程度最高,且主要发生在盆地西南部和祁连山区。柴达木盆地土地开发利用综合指数持续增加,表明土地利用类型不断向开发利用等级高的方向转化但变幅不大;盆地土地利用总体稳定、局部转化剧烈。本研究可为土地资源评价和土地利用规划及可持续发展提供参考。

Based on the European Space Agency(ESA)Climate Change Initiative(CCI)Land cover products,this paper examines the land use/cover data of four years(2000,2005,2010 and 2015)for the Qaidam basin,and calculates the land use/cover type change matrix.Then,using the matrix,we evaluate the land use transfer priority direction and formulate a new land use grade index.The results show that in this basin,the main land use types were grassland and unused land,accounting for 51.6%and 44.9%of the basin,respectively.Water area,cropland and forestland were in a decreasing order of land cover proportion,and the proportion of residential land was the smallest.During the past 15 years,cropland,grassland and residential land areas have been increased,while unused land decreased,both in a monotonous trend.Of the transformation between different land use/cover types,the one between grassland and unused land was the largest,and it occurred mainly in the southwest of the basin and the Qilian mountains.The land use grade index of the Qaidam basin shows a continuing growth but in a small range,which means the change in land use/cover has been stable globally and sharp locally.The study provides an approach for land resource assessment,land use planning and sustainable management.