摘要
利用山西省吉县蔡家川流域 1∶10 0 0 0地形图及 2 0 0 3年秋季时相的QuickBird卫星遥感影像 ,结合野外调查资料进行景观制图 ,并与数字高程模型 (DEM)数据进行图层叠加分析 ,研究典型嵌套流域内不同景观类型随地形变化呈现出的分异特征及变化成因 .结果表明 :①在较大尺度上 ,地形因素是本区景观分异的首要因素 ;② 2 0世纪80年代以来的封山育林与生产性造林以及近年来实施的退耕还林 ,是局部地区景观组分在各种地形梯度上显著变化的根本原因 ,自然恢复过程对于这种格局变化也起到了积极的促进作用 ;③目前流域内人为的干扰活动主要是过度放牧 ,集中在自然景观与人为景观过渡的中游地带 ;④在本流域高程 10 0 0～ 12 0 0m、坡度 2 5°～ 35°、坡向半阴坡的关键地区 ,应采用科学的人工促进自然生态恢复措施 ,逐渐增加近自然景观组分 。
Quick Bird satellite images taken in the fall of 2003, combined with field survey information and a topographic contour map (scale =1∶10 000) were used for landscape mapping of the Caijiachuan watershed of Shanxi Province. Using layer overlay analysis of the landscape pattern maps and a digital elevation model (DEM), the authors studied the distribution variation pattern of different landscape types along the topographic gradients and its causes in this typical, nested watershed. The results show: ① topographic characteristics are critical for the spatial variations of landscapes on a large scale map; ② the closure of land for reforestation and productive reforestation since the 1980s and the conversion of farmlands to forestland in recent years are the primary causes for the significant variation of the elements in landscape distribution patterns along topographic gradients in local regions; furthermore, natural recovery processes also give an impulse to the change in the pattern; ③ the major human disturbance activity in the Caijiachuan watershed-overgrazing is centralized in the area between natural and artificial landscapes; trampling of vegetation accelerates soil erosion and water loss, to which the local government should attach much importance; ④ the authors think that artificial measures should be adopted to stimulate natural regeneration, to increase the near-natural landscape elements and to reduce negative human activities in the key regions of this watershed, where the elevation is 1 000～ 1 200 m and the slopes are between 25° and 35° and half-shaded.
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2005年第2期43-48,共6页
Journal of Beijing Forestry University
基金
"973"国家重点基础研究发展规划项目 ( 2 0 0 2CB1115 0 3 )
国家科技攻关项目 ( 2 0 0 1BA5 10B0 1)
关键词
景观格局
地形分异
数字高程模型
人为干扰
黄土丘陵
landscape pattern, topographic variation, digital elevation model, human disturbance, Loess upland
