衡阳紫色土丘陵坡地植被恢复对植物群落结构及多样性的影响

摘要

采用“空间序列代替时间序列”的方法，将植被恢复阶段划分为演替前期、演替中期和演替后期，并测定每一阶段植物群落特征及多样性指标.结果表明：(1)随着演替进行，地上生物总量和中旱生物植物生物量显著增加( P<0.05)，中生植物生物量的大小顺序为中期>后期>前期( P<0.05)，旱生植物生物量的大小顺序为中期>前期>后期(P<0.05)；(2)随演替进行，Shannon-wiener多样性指数(H)、Simpson多样性指数(H′)、Pielou均匀度指数(E)、Simpson均匀度指数(E′)与Simpson优势度指数(D)显著减小(P<0.05)，物种丰富度指数(S)的大小顺序为中期>前期>后期(P<0.05)；(3)随演替进行，群落优势种狗尾草(Setaria viridis)和狗芽根(Cynodon dactylon)的重要值显著增加( P<0.05).图1，表3，参23.%The re-vegetation stages were classified into successive early stage,middle stage and later stage by using an approach of spatial sequence instead of temporal sequence, and the plant community characteristics and bio-diversity index in each plot were measured.The results showed that: (1) In the process of succession, the total aboveground and middle-xerophyte biomass significantly increased ( P<0. 05) ,that of mesophyte were followed the order as middle stage>later stage>early stage( P<0.05) ,and that of xerophyte were followed the order as middle stage>early stage>later stage(P<0.05); (2)In the process of succession,Shannon-wiener diversity index( H) ,Simpson diversity index( H′) ,Pielou evenness index(E),Simpson evenness index(E′) and Simpson dominant index(D) significantly decreased(P<0. 05),the richness index was followed the order as middle stage>early stage>later stage(P<0.05);(3) The important values of dominant species such as Setaria viridis and Cynodon dactylon significantly in-creased in the process of succession(P<0.05).1fig.,3tabs.,23refs.