喀斯特石漠化的形成过程及阶段划分

以群落类型、乔灌层盖度、群落生物量、群落高度和枯落物总量5个因子为基本指标,采用主成分分析和系统聚类分析相结合的方法对贵州喀斯特地区大量样地进行了分析,将喀斯特石漠化的形成过程划分为初期、中期、后期和末期阶段4个阶段。对石漠化的形成过程和阶段特征进行了分析,结果表明:石漠化形成过程中整个土地系统退化的主要原因是植被系统的退化,它在人为干扰下受到破坏而导致了土壤子系统及小气候环境子系统的退化,子系统之间表现出相互促进、相互转化的正反馈循环。石漠化的形成过程实质上是土地生产力的退化和丧失过程。

A Study on Forming Process and Stages of Karst Rocky Desertification

Based on the amount of samples data with 5 factors such as community type,arbor and shrub coverage,biomass, community height and litter amounts using methods of principle components analysis and clustering analysis,the results indicated that the forming process of rocky desertification could be divided into 4 stages: initial stage,mid-stage,last stage and the end stage.Analyses on forming process and stage characters showed that the main reason of land system degraded in forming process of rocky desertification was degradation of vegetation sub-system,caused by human disturbance on the degradation of soil sub-system and micro-climate environment sub-system. A positive feedback was formed of mutual cycle and interaction among each sub-system.The degradation and losing of land productivity were essential of rocky desertification forming process.