【作者】 彭建；

【导师】 蔡运龙；

【作者基本信息】 北京大学 ， 自然地理学， 2006， 博士

【摘要】 喀斯特地区是典型的生态环境脆弱区。我国西南地区是全球喀斯特集中分布的三大片区之一——东亚片区的中心,近几十年的土地利用变化衍生出一系列生态环境问题,直接威胁到区域社会经济的持续发展和相邻地区的生态安全。近年来,对此问题的研究尽管已经取得了一定成就,但远不能满足需求。本文以位于贵州中部的猫跳河喀斯特流域为对象,以1973年的MSS和1990年、2002年的TM等卫星影像为数据源,运用RS-GIS-GPS集成技术,研究了该地区在过去三十年间土地利用/覆被变化的过程、驱动机制,运用CLUE-S模型模拟、预测了该流域在不同目标情景模式下的土地利用/覆被变化,并运用景观生态学的方法对猫跳河流域过去三十年间的土地利用/覆被变化以及未来不同情景模式下的土地利用/覆被变化的生态效应进行了评价。研究表明:⑴在过去三十年间,猫跳河流域土地利用/覆被发生了比较剧烈的变化。从数量上来看,1973～1990年,变化幅度从大到小依次是旱地>灌木林>水田>裸岩地>其他林地>有林地>灌草地>农村居民点>交通工矿用地>水域>城镇用地;1990～2002年则为旱地>灌草地>有林地>水田>裸岩地>农村居民点>灌木林>水域>交通工矿用地>城镇用地>其他林地。⑵各地类的变化方向和强度存在较大差异。1973年至2002年,耕地总量经历了先增后减的变化。其中水田先减后增,旱地先增后减。有林地处于持续增加之中。灌木林和其他林地在70、80年代经历了较大幅度减少,1990年后,两者变动均不大。灌草地总量在1973～1990年间变化不大,但转入和转出比较频繁,进入90年代后,灌草地显著增加。有林地、水域和建设用地持续增加。裸岩地在70、80年代期间发生了显著的扩张,进入90年代后逐渐缩减。⑶猫跳河流域土地利用/覆被变化存在着较为明显的空间差异,这种差异表现在丘原区和峡谷区之间、丘原区和峡谷区内部不同人类干扰强度地区之间。代表不同自然、人文地域背景的红枫湖镇、羊昌乡、龙场镇以及谷堡乡在土地利用/覆被变化的方向和幅度方面互不相同,在猫跳河流域这样一个面积不大的区域,不同区域土地利用/覆被变化的异质性比较明显。⑷流域土地利用/覆被变化是多种因素交织在一起共同作用造成的,气候变化、人口变化、经济发展、农业技术进步、富裕程度、市场与物价、燃料结构、制度与体制、政策法规等因素的变化驱动着研究区土地利用/覆被的变化。⑸CLUE-S模型能对喀斯特山区土地利用/覆被变化进行较好的模拟和预测。单纯的生态安全目标下林地、灌草地等地类显著增加,裸岩地和耕地大幅减少。单纯的食物安全目标下灌草地会减少,石漠化土地出现明显扩张。经济发展目标下建设用地快速扩张,优质良田会被大量挤占。综合发展模式比较全面地考虑到了经济发展、生态保护以及粮食安全等需要,土地利用变化比较合理。⑹70、80年代,猫跳河流域的景观趋于破碎化,拼块的复杂程度和多样性降低,流域生态服务价值指数从3626.58降到3343.47,这一期间的土地利用具有明显的不可持续性。进更多还原

【Abstract】 It is well known that karst areas are typically ecologically fragilie. The Southwestern China is the centre of East Asia Karst Area, which is one of the three biggest karst areas around the world, where soluble rocks (mainly carbonate rocks) cover a area of 540 000km2, and about 0.1 billion people live. Over the past few decades, land use changes there have brought forth a series of severe ecological and environmental problems, which directly threaten the sustainable development of local society and economy and also the ecological security of nearby areas. Although some academic achievements have been made on the issues, it is far from enough. Employing the satellite images of Landsat-MSS and Landsat-TM and the integrated techniques of RS, GIS, and GPS, the authors, with Maotiaohe River Basin as a case, studied the process and driving factors of land use /cover changes since the beginning of 1970s, and modeled the possible land use/cover changes scenarios in the coming 10 years based on CLUE-S model, and then made an ecological evaluation on effect of the changes over the past 30 yeas as well as in the coming 10 years by using theory and method of landscape ecology. In this research, the authors, from the angle of international LUCC studies, threw much light on the land use/cover changes in the basin and also the derived ecological and environmental problems such as karst rocky desertification. The study shows that:⑴Over the past 30 years, land covers in Maotiaohe River Basin have experienced dramatic change. In quantitative terms, from the year of 1973 to 1990, the absolute change extent obey the following sequence: dry field (8.61%) > shrub land (-7.06%) > paddy field (-3.52%) > naked land (2.12%) > tea land (-1.92%) > forest land (1.06%) > grassland (-0.61%) > rural settlement (0.58%) > traffic and industrial land (0.53%) > water (0.1%) > urban land (0.06%); and from 1990 to 2002, dry field (-9.79%) > grassland (3.33%) > forest land (3.18%) > paddy field (1.98%) > naked land (-1.45%) > rural settlement (0.85%) > shrub land (0.73%) > water (0.48%) > traffic and industrial land (0.47%) > urban land (0.27%) > tea land (0)⑵From the year of 1973 through 2002, the cultivated land increased and then decreased. The paddy field decreased in 1970s and 1980s and then increased after 1990, in 1973, 1990, and 2002, the percentage of paddy field in the whole catchment is respectively 18.54%, 15.02%, and 17.00%; meanwhile, dry field experienced opposite change with the percentage respectively 22.41%, 31.02%, 21.23%. The forest land kept on expanding over the past 30 years with the 1990s as a更多还原