基于景观生态学的喀斯特生态脆弱区土地利用/覆被变化评价——以贵州猫跳河流域为例

通过运用遥感、地理信息系统以及全球卫星定位系统等技术手段,借助于景观生态学中的景观格局指数以及构建生态价值指数,对位于贵州中部典型喀斯特地区的猫跳河流域1973年以来的土地利用/覆被变化及其对整个区域生态环境状况的影响以及近30年来土地利用的合理性进行了评价。研究表明,在过去的30年间,研究区的土地覆被发生了显著的变化,并对区域的生态环境造成了深刻的影响。1973-1990年,猫跳河流域的景观趋于破碎化,斑块总数从3438个增加到3619个,生态服务价值指数从3626.58降低到3343.47,土地利用具有明显的不可持续性;1990-2002年,猫跳河流域的景观破碎度降低,斑块数量从1990年的3619个减少到3312个,整个流域的生态服务指数从3343.47上升到3738.4,生态环境质量开始向好的方向发展。

Assessment on land use/cover change in karst areas based on landscape ecology——A case study at Maotiaohe river basin, Guizhou, China

Land use/cover change has been one of the key issues of international LUCC community since mid 1990s. However, the land use/cover change and its effects in karst areas with fragile ecosystems and dramatic land use change have not been attached enough importance, as almost turns out to be a vacant field in international LUCC research. By utilizing the integrated techniques of RS, GIS, and GPS, and employing pattern index in landscape ecology and new-established ecological value index(EVI), the authors made a case study on the land use/cover change and its effect on the eco-environmental quality at Maotiaohe river basin, and also evaluated the rationality of land use over the past 30 years. The results show that the land covers have experienced dramatic change, which brought deep influence on regional eco-environment. From 1973 through 1990, the landscape in the study area tended to be more and more fragmentized with the number of patches increasing from 3438 to 3619, and the EVI decreasing from 3626.58 in 1973 to 3343.47 in 1990, which implies the land use in the period was not sustainable. From 1990 to 2002, the landscape in the study area became less fragmentized, and the number of total patches decreased from 3619 in 1990 to 3312 in 2002. As a result, the Ecological Value Index increased from 3343.47 to 3738.40, and the general eco-environmental quality tended to be better. Besides, the case study demonstrates that the EVI put forward by the authors in the paper can well describe the ecological effect of land cover change on regional scale, which makes the index systems more perfect.