黄河源区1990―2020年土地利用变化分析

Analysis of land use changes in the source region of the Yellow River from 1990 to 2020

为给黄河源区土地管理和土地资源可持续利用提供依据,监测了1990、1995、2000、2005、2010、2015、2020年黄河源区7期Landsat TM/OLI原始遥感数据,利用ArcGIS软件对黄河源区近30年土地利用情况和动态变化进行统计分析,探讨了源区土地利用变化特性、规律及趋势.结果表明:(1)1990―2020年,黄河源区土地利用面积呈波动状态.林地、未利用地面积减少,草地、未利用地面积变化幅度最大,草地面积增加了5857.029 km2,未利用地减少了6311.123 km2.(2)源区近30年土地利用类型主要为草地,约占黄河源区总面积的80%.2005年后,源区西部的未利用地基本消失,转化为草地,说明源区生态文明建设取得明显成效.(3)近30年黄河源区土地利用动态度呈现波动变化,源区综合土地利用动态度为0.214%,且2010―2015年土地利用率最低.

To provide a basis for land management and sustainable use of land resources in the source region of the Yellow River,7 phases of Landsat TM/OLI raw remote sensing data in the source region of the Yellow River in 1990,1995,2000,2005,2010,2015 and 2020 were examined,the land use status and dynamic changes of the source region of the Yellow River in recent 30 years were analyzed statistically by ArcGIS software,and the characteristics,patterns and trends of land use change in the source area were investigated.The results showed that:(1)From 1990 to 2020,the used land area of the source region of the Yellow River was fluctuating.The area of woodland and unused land decreased,and the area of grassland and unused land in the source area changed the most.Among them,the area of grassland increased by 5857.029 km2,and the area of unused land decreased by 6311.123 km2.(2)The land use type of the source area in the last 30 years was mainly grassland,which accounted for about 80%of the total area of the source region of the Yellow River.After 2005,the unused land in the western part of the source area almost disappeared and was transformed into grassland,which indicated that the construction of ecological civilization in the source area achieved remarkable results.(3)The dynamic level of land use in the source region of the Yellow River fluctuated in the last 30 years.The dynamic level of comprehensive land use in the source region was 0.214%and the land utilization rate was the lowest from 2010 to 2015.