木美地下河流域主要植被类型物种多样性与恢复对策

研究了云南省木美地下河流域岩溶区主要植被类型的物种多样性,并将其与生境相似的广西田阳县 南部岩溶区植物群落物种多样性作比较。结果表明,云南木美地下河流域存在四种植被类型:草丛、灌丛、幼 林、成年林,其物种多样性均比广西田阳县同类型群落低,以Simpson指数为例,田阳灌丛为27．79,而木美灌 丛中最高仅为10．99,田阳幼林为25．24,木美仅为4．69。随着植被恢复演替的进展,木美群落物种多样性逐 渐增加,至成年林群落物种多样性达到最大值,外来种消失。从对比分析结果可知,要保护木美流域的物种多 样性、防止外来种入侵、维护流域生态系统安全,则应重新整合土地资源,改变土地利用方式,实施退耕还林工 程,提高植被覆盖率。

Species diversity and restoration strategies of vegetation types in Mumei Underground River Areas

Species diversity was comparatively examined between the community in a Karst area of Mumei Underground River in Yunnan and that in a similar area in Southern Tianyang County of Guangxi. The result showed that there were 4 types of vegetation such as herb, shrub,youth trees and mature forestes in Mumei Underground Area, while its species diversity were all lower than the similar type of community in Tianyang. Taking Simpson index as an example, the value of shrubs in Tianyang area were 27. 79, while in Mumei the highest of all shrubs was only 10.99;and for youth tees in Tianyang area,it was 25.24,while for Mumei,only 4.69. With the succession of vegetation restoration in progression, the diversity indexes of the community in Mumei were gradually increasing,and reached the highest in the mature forest,and introduction species disap- peared. According to the analysis Tesults,changes and adjustment in land use and resources should be emphasized,and projects of returning plantation for forestry or methods of improving the vegetation cover should also be encouraged in order to prevent the foreign species and protect the ecological safety of the area.