近16年来黄土丘陵沟壑区土地利用动态变化及驱动因素分析——以陕北黄土高原的子长县为例

在RS和GIS技术支持下,以子长县1990、1999和2006年3期TM/ETM卫星影像为基础数据,结合野外实地调查资料,应用土地利用动态度、年变化率、土地转移矩阵等方法对子长县过去16年间的土地利用变化特征及其驱动因素进行分析。结果表明：1）1990—2006年,子长县土地利用变化表现为耕地和未利用地显著减少、牧草地和林地显著增加、水域先减后增以及建设用地持续增加的总体特征;2）耕地、牧草地、林地和未利用地的面积变化较为剧烈,且几乎所有用地类型在1999—2006年的年变化率较1990—1999年更为明显;3）耕地和未利用地的减少在各土地类型中最为明显,二者的减少是因为林草地面积大量增加,坡耕地等成为林草地面积增加的主要来源;4）社会、经济、政策等人文因素对子长县的土地利用变化起着重要作用,而政策因素则是导致土地利用结构发生变化最主要的驱动力。

Landuse change and its dynamic driving forces in Hilly-Gully Area of Loess Plateau:A case study in Zichang County from 1990 to 2006

Based on RS/GIS techniques,the TM/ETM satellite images in Zichang County of 1990,1999 and 2006 were used as basic data,field investigation,land use dynamic,annual change rates and land transfer matrix were used to analyze the land use characteristics and its driving factors.The result shows：1） from 1990 to 2006,the cultivated land and unused land decreased,while the grassland,forest,construction land increased significantly,the water area increased at beginning and then decreased;2） during this period,the cultivated land,grassland,forest and unused land changed dramatically,and the change rates occurred more sharply from 1999 to 2006 than the period from 1990 to 1999;3） cultivated land and unutilized land decreased significantly among all kinds of lands,due to the increase of grass land and forest land contributed by the cultivated land;4） the human factors such as society,economy,policy are playing important roles in the change of land utilization,especially the policy factor has been the maim driving power for the change of landuse structure.