近30年秦岭山地商洛段林地类型时空变化及其驱动力

在遥感和地理信息系统(GIS)技术的支持下,以商洛地区1978年多波段扫描仪(MSS)和1990、2000、2006年专题制图仪(TM)四期遥感影像为基础,利用ERDAS软件的监督分类与GIS的空间分析功能,提取了商洛地区各类型林地的动态变化信息,研究分析了近30年来商洛地区各种类型林地的时空变化特征.结果表明:林地的总面积由12584.55km2增加到14479.44km2;针叶林、灌丛面积增加,而针阔混交林、阔叶林的面积减少,低海拔地区较高海拔地区变化剧烈.林地破碎化程度严重,且内部结构发生了根本性的变化,大多数阔叶林被灌丛取代.区域社会经济财力、农民收入及适耕地的多少是林地类型变化的主要驱动力.

Spatial-temporal change and its driving forces in woodlands in the Shangluo Section of the Qinling Mountains over the last30 years

Based on four remote sensing images (MSSin 1978 and TMin 1990,2000 and 2006),the spatial-temporal changes of woodlands in the Shangluo section of the Qinling Mountains were analyzed with the support of ERDASand GIS.Over the past 30 years,the total area of the woodlands increased from 12584.55 km² to 14479.44 km².The area of coniferous forests and shrubs both increased,while the area of coniferous-broad mixed forests and latifoliate forests decreased.The change of various woodlands in the low-elevation regions was more serious than that in high-elevation regions.The woodlands became fragmented and their internal structure has fundamentally altered,i.e.most of the latifoliate forests have been replaced by coniferous forests.The major driving forces for such changes are from regional socio-economic resources,farmers' incomes and the demands for arable land.