基于GIS与RS下的1990—2015年塔里木河流域LUCC及景观格局时空分析

GIS and RS-based analysis on temporal and spatial changes of LUCC and landscape patterns in Tarim River Basin from 1990 to 2015

针对西北干旱区流域生态环境恶化、人-地关系矛盾突出等问题,以新疆塔里木河流域为例,以Landsat卫星影像为主要信息源,通过解译数据分析了研究区1990-2015年土地利用变化特征。结果表明:1990-2015年研究区土地类型变化综合动态度3.16%,土地利用格局变化明显,土地利用类型单一动态度依次为耕地(2.11%)、建设用地(0.64%)、水体(0.06%)及未利用地(0.002%),林地(-0.25%)与草地(-0.21%)面积25 a间持续减少。耕地的持续扩张导致流域内草地和水体斑块个数成倍增加,斑块破碎化程度进一步加剧:通过对遥感解译数据、公开统计面积及相关普查成果等多源数据的比较印证,得出2015年塔里木河流域较为准确的流域耕地面积37531 km^2,25 a间流域耕地面积增加12940.92 km^2。研究成果为未来改善流域生态环境、促进流域生态文明建设、土地资源可持续利用及其管理等决策提供基础信息支撑,对我国西北干旱区土地利用管理规划和生态环境保护具有实际意义。

Aiming at the problems of the deterioration of eco-environment and the contradiction between human being and land resources in the arid regions of Northwest China and taking Tarim Basin in Xinjiang as a study case and the Landsat image as the main information source,the variation characteristics of the land use in the study area from 1990 to 2015 is analyzed through interpreting the relevant data.The result shows that the comprehensive dynamic degree of land type change in the study area is 3.16%from 1990 to 2015 with an obvious change of the land use pattern therein,while the single dynamic degree of the land use type exhibits a sequence of cultivated land(2.11%),construction land(0.64%),water body(0.06%)and unused land(0.002%),forest land(-0.25%)and grassland(-0.21%)in turn,in which the areas of forest land and grassland are decreased in the past 25 years.The continuous expansion of cultivated land leads to the many-fold increases of the number of the imaging patches of grassland and water body in the basin along with a further aggravation of the patch fragmentation degree:through the demonstration from the comparison among multi-source data,i.e.the interpretation of remote sensing data,the open-statistical areas,the relevant census results,etc.,it is obtained that the more accurate cultivated land area is 37531 km^2,and then the area of cultivated land is increased by 12940.92 km^2 in the past 25 years.The study result provides a basic information support for the decision-making of improving the eco-environment and promoting the ecological civilization construction of the river basin as well as the sustainable use and management of the land resources in the river basin,which has a practical significance for the management and planning of the land use and the eco-environment protection in the arid regions of Northwest China.