不同强度人为干扰对毛竹林植物多样性的影响

Effects of Different Artificial Disturbances Intensities on Plant Diversity in Moso Bamboo Forest

为了比较不同程度人为干扰下毛竹林下植被的群落组成结构,研究了人工干扰对毛竹林下植被群落的影响。本研究以杭州市临安区为例,选择了人工干扰程度不同的9个样地,并在每个样地中设置样方,测量植被的多样性,调查植被的种类、株数等,同时计算其重要值、丰富度指数(S)、Simpson优势度指数(D)、Shannon-Wiener多样性指数指数(H)、Pielou均匀度指数(J_(sw))、Alatalo均匀度指数(E)。结果表明:不同强度人为干扰下的毛竹林群落科属种组成发生了明显的变化,表现为中度干扰下毛竹林植被的科属种数目最多,轻度干扰次之,重度干扰最小;而乔木层物种数在轻度干扰下最多,灌木层物种数在中度干扰下最多,草本层物种数在重度干扰下最多;毛竹林乔木层和灌木层中S、D、H、J_(sw)和E值总体上均呈现出中度干扰最大、轻度干扰次之、重度干扰最小的变化趋势,但草本层中各项指标值随着干扰强度的增大而增大。因此,保持适度的人为干扰、维持植被多样性对竹林经营过程有着重要的意义。

In Lin' an experiment area,we selected 9 sample plots with different intensities of artificial disturbance and set quadrats in every plot for measuring the vegetation diversity,investigating the species and number of plants,and calculating the species richness index S,Shannon-Wienner index H,Simpson index D,Pielou evenness index J_(sw)and Alatalo evenness index E,in order to compare the composition structure of Moso bamboo forest community of different artificial disturbances and try to find the influences of artificial interference on their diversity and stability. The results showed that there are obvious changes in the species composition of bamboo forest community under different human disturbances. The species number generally is the highest under the medium disturbance,followed by slight disturbance and severe disturbance. However the species in the arbor layer are the most in number under the slight disturbance,the number of shrub species is the highest under medium disturbance,and the number of herb species is the most under severe disturbance. The values of S,D,H,J_(sw)and E of the arbor layer and shrub layer in Moso bamboo forest in general are the largest under medium disturbance,following by slight disturbance and severe disturbance,but the indicators in the herb layer increases with the increasing intensity of the disturbance. Therefore,it is of great significance to maintain the proper artificial disturbance in order to conserve the diversity of vegetation in the bamboo forest operation.