衡阳紫色土丘陵坡地恢复过程中植物群落结构及多样性的变化

Changes of Plant Community Structure and Bio-diversity During Re-vegetation on Sloping-land with Purple Soils in Hengyang of Hunan Province

探讨衡阳紫色土丘陵坡地不同恢复阶段植物群落结构及多样性的变化。以典型的衡阳紫色土丘陵坡地不同植被恢复阶段为研究对象,采用空间序列代替时间序列的方法,选用立地条件基本相似的演替初期(Ⅰ),演替中期(Ⅱ)和演替后期(Ⅲ)3个恢复阶段,通过调查取样和实验分析,分析不同恢复阶段植物群落结构及多样性。(1)从Ⅰ、Ⅱ到Ⅲ,植物地上生物总量与中旱生植物生物量显著增加(P<0.05),中生植物生物量与旱生物植物生物量先升后降,呈现出"n"型变化规律(P<0.05);(2)随着植被恢复的进行,优势种群即狗尾草种群和须芒草种群的重要值显著下降(P<0.05);(3)Patrick丰富度指数(R)的大小顺序为:Ⅱ>Ⅰ>Ⅲ(P<0.05);Simpson优势度指数(D)的大小顺序为:Ⅲ>Ⅱ>Ⅰ(P<0.05);Shannon-Wiener多样性指数(H)和Pielou均匀度指数(E)的大小顺序为:Ⅰ>Ⅱ>Ⅲ(P<0.05)。研究结果将丰富该地区植物生态学和恢复生态学的内容,为衡阳紫色土丘陵坡地生态系统的恢复和重建提供了重要依据。

The paper aims to study the changes of plant community structure and bio-diversity during re-vegetation on sloping-land with purple soils in Hengyang of Hunan Province,south-central China.By usingthe space series to replace time series,three typical sampling plots,ini-phase（Ⅰ）,mid-phase（Ⅱ） and ana-phase（Ⅲ）,were selected to study the plant community structure and bio-diversity,the three re-vegetationstages on sloping-land with purple soils were similar and typical,and denoted three different successive stagesin Hengyang of Hunan Province.The results showed that：（1） from Ⅰ,Ⅱ,to Ⅲ,the total aboveground biomassand middle-xero-phytes biomass significantly increased（P〈0.05）,while that of mesophyte and xerophytesincreased first and then decreased,showing ＂n＂type（P〈0.05）;（2） important values of the dominantpopulations（including Setaria viridis and Miscanthus sinensis） significantly decreased（P〈0.05）;（3） Patrickrichness index（R） followed the order asⅡ〉Ⅰ〉Ⅲ（P〈0.05）,and the order of Simpson dominant index（D）was Ⅲ〉Ⅱ〉Ⅰ（P〈0.05）,the order of Shannon-Wiener diversity（H） and Pielou evenness index was Ⅰ〉Ⅱ〉Ⅲ（P〈0.05）.This study,to some degree,enriches and broadens the vegetation ecology and restorationecology of the studied area and provides important theoretical basis for ecosystem restoration and reconstruction on sloping-land with purple soils in Hengyang of Hunan Province,central-south China.