基于Landsat TM的塔里木河下游土地利用变化与图谱研究  

Land Use Change and Mapping in the Lower Reaches of the Tarim River based on Landsat TM Images

作　　者：闫文浩[1] 任志远[1] 张翀[1] 

机构地区：[1]陕西师范大学旅游与环境学院,西安710062

出　　处：《资源科学》2009年第1期142-151,共10页Resources Science

基　　金：国家自然科学基金项目(编号:40771019)。

摘　　要：利用1990年～2004年的4、3、2(RGB)波段合成影像解译结果,结合景观生态学理论和地学信息图谱理论对塔里木河下游的土地利用/覆被变化进行了研究,并分析了其生态环境效应。结果表明呈:近14年来,塔里木河下游的耕地、林地和草地面积呈减少趋势;未利用地面积呈增加趋势;水体景观面积也呈增加趋势,这主要是由于近年来向塔里木河下游多次输水的结果。从景观格局指数上看,多样性指数变化不大,程度略低,1990年和2004年分别为0.95和0.75,表明整个区域的景观异质性减弱,生态系统趋于不稳定状态。整个研究区的破碎化指数较小,基质特征较明显。景观优势度较小,表明区域内景观类型所占比例差别不太大。总的来说,塔河下游生态环境整体尚处于不良状态,主要是因为有大部分的未利用地景观作为基质。研究区LUCC除受暖温带大陆性干旱气候的影响外,人类活动改变地表水的地域分配及对天然植被的破坏,则是引起生态环境退化的主要原因。This paper analyzes land use/cover changes and eco-environmental response in the lower reaches of the Tarim River from 1990-2004 using landscape ecology theory and data from three sets of TM images. Land use/cover change in the lower reaches of the Tarim River over the study period included a sharp increase in uncultivated land and water bodies, and a decrease in arable land, forest land and grassland. Water bodies and grassland became more fragmented and interspersed, and the increase in the area of uncultivated land was at the cost of encroachment on grassland. The landscape pattern became less fragmented and the shape of the landscape components became less complex, and the predominance index increased. The Shannon diversity index decreased from 0.95 to 0.79, while the Shannon evenness index decreased from 0.42 to 0.31. This indicates that the landscape is becoming more simple and unbalanced, but is more capable of withstanding interference. Except for the effects from the warm-temperate continental arid climate, human activities （such as changing the spatial distribution of surface water and destruction of natural vegetation） are the main causes of environmental degradation. The ecological environment in the region as a whole is still in poor condition, and the fundamental reason for this phenomenon lies in the increase in population and inefficient reclamation, causing water to dwindle in the lower reaches. The conversion of surface water to groundwater was reduced. With higher levels of evaporation and water transpiration, some vegetation growth was inhibited, and shallow root plants killed. Due to the lack of natural vegetation to protect the sandy surface, ecological problems in the lower reaches of the Tarim River are becoming increasingly serious. This matter deserves careful consideration in the context of the larger environment, as only the change in spatial and temporal distribution of water resources and impact of human activities have caused such a serious degradation of the ecological environm

关 键 词：土地利用 LandsatTM 图谱 景观 塔里木河下游 

分 类 号：S159.2[农业科学—土壤学]