摘要
喀斯特山区生态系统已经和正在经历各种人为的干扰、破坏和不合理使用。植被退化是生态系统退化的最典型外在特征。在对滇东的3个喀斯特山村和自然保护区的25个喀斯特植被样地的植物群落学特征,繁殖体库和土壤基质进行调查研究后发现:喀斯特山地植被退化是一个渐进的逆向演替过程,人和动物的选择性、物种的适应性和持久性能力决定着物种及其繁殖体的存在与消亡。某些物种由于具有较强的萌生能力和较高的持久性,其无性繁殖体能在反复砍伐后仍然保存于一些石质缝隙之中。伴随植被退化,土壤有机质和养分不断流失。以物种组成、群落高度、繁殖体库、土壤、生物量与参照群落间的相异性指数为指标,通过聚类分析将滇东的喀斯特退化植物群落分为顶级群落、乔林、灌乔、灌丛灌木、草灌和草本群落6个阶段。喀斯特退化植被的恢复应该充分考虑到这种植被退化的阶段性,根据各阶段的特点补充不同数量和种类的当地物种繁殖体,改善土壤基质性状并配以抚育措施。
Karst ecosystem is being and had been suffered from manmade disturbances, damage and inadequate explorations. Vegetation degradation is the typical characteristic of ecosystem degradation. After study on vegetative structure and composition, propagule and soil of 25 vegetative ecosystems at three villages and one natural reserve in karst upland in Eastern Yunr/an, we found that vegetation degradation was a gradual, anti-successional process in which species composition and propagule bank were determined by the selection force of man cutting and animal grazing, adoptability and persistent capability of individuals. Due to high resprouting capability and high persistent capability, some root systems can survive for very long time in some lacune and rock gaps from human cutting and animal grazing. Soil O. M and nutrient were eroded with the degradation process. Using the dissimilarity index of species composition, height of community, propagule bank, soil nutrient pool and biomass between degraded vegetation and matured forest, karst vegetative communities was clustered into groups that corresponded to 6 stages of vegetation degradation： climax→tree→bush tree→bush→grass bush→grass. Restoration of karst vegetation should take into consideration of the characteristics of each stage. We recommended propagule inputting of local species or adopted species after study on the size of existing propagule bank, followed by amendment of soil base and management of existing tree propagules.
出处
《山地学报》
CSCD
北大核心
2005年第4期425-430,共6页
Mountain Research
基金
云南省自然科学基金(2002C0004Z)资助
福特基金(美国)会(项目号:1015-0281)。~~
关键词
喀斯特山地
植被退化
等级
恢复策略
karst upland
vegetation degradation
grade
restoration strategies
作者简介
沈有信（1966-）,男,汉族,云南昆明人,中科院西双版纳热带植物园助理研究员,主要从事恢复生态学研究. [ShenYouxin （1966 - ）, male, associate researcher of Xishuangbanna Tropical Botanical Garden, CAS, specialized on ecological restoration research, Tel： 0871 - 5160910, E - mail： yxshen@xtbg. ac. cn]
