湖北远安县阔叶混交林乔木树种生态位特征分析

Analysis of niche characteristics of main tree species in broad-leaved mixed forest in Yuan′an County of Hubei Province

建立在森林普查基础上,采用样方调查法研究远安县广泛性天然次生落叶阔叶混交林群落,在5个乡镇设置5个样地,对区域资源位群落调查分析,统计重要值与测度生态位,结果表明:①调查落叶阔叶混交林乔木物种37种,隶属16科28属,具有较高的物种丰富度,树种组成复杂,代表了分布较普遍和数量上有一定优势的树种;②重要值(IV)介于0.01~0.174,优势种群不明显,群落物种内部环境中绝大多数资源利用均衡,树种之间关系为相互共生共存,生态位宽度(Bsw,Ba)值与值变异系数呈负相关关系,不同树种IV值与生态位宽度值之间没有明显的正相关关系,生态位宽度值与其IV值大小无关;③生态位宽度(Bsw,Ba)值区间在0.2~0.6和0.2~0.8,值存在差异,波动与排序基本一致,绝大部分乔木树种对资源利用的状况和特化程度相近;④乔木树种生态位重叠的种对数占83.8%,对环境的适应普遍具有一致性,对环境资源有共享趋势;⑤生态位相似性比例0.4≤Cik<0.6占33.2%,Cik<0.4占45.5%;Cik值整体较小,波动较大,物种之间存在生态位分离现象,对资源的利用趋向于互相弥补,种群对群落环境资源Cik的分享比较充分,群落内物种对资源的利用程度有较高的相似性。该类型天然林近自然经营下,能维持生物多样性和生态系统稳定性,建立稳定植物群落,自然更新和寻求最理想的混交树种模式,保持树种之间共生共存,资源充分利用,环境互补,资源环境有效地利用,以提高森林生态系统的综合生产力。

On the basis of forest census,a quadrat survey method was used to study the communities of the extensive natural secondary deciduous broad-leaved mixed forest in yuan'an county.Five sample plots were set up in five towns and townships to investigate and analyze the regional resource niche community,and to calculate the important value and measure the ecological niche.The results show that:①Investigate 37 arbor species in deciduous broad-leaved mixed forest,belonging to 16 families and 28 genera,with high species richness and complicated tree species composition,which represents the more widespread and quantitatively superior tree species;②The important value is between 0.01~0.174,dominant population is not obvious,In the inner environment of the community,most of the resources were utilized in a balanced manner,the relationship between tree species was symbiosis,the variation coefficient of niche width value and important value was negatively correlated,there was no obvious positive correlation between important value and niche width value,and the niche width value had nothing to do with its important value.③The values of Bsw and Ba ranged from 0.2 to 0.6 and 0.2 to 0.8,and the values were different.The fluctuation was basically consistent with the ranking.The utilization status and specialization degree of most tree species were similar.④The number of species with niche overlap of tree species accounted for 83.8%,and their adaptation to the environment is generally consistent.⑤Niche similarity ratio 0.4≤Cik<0.6 accounted for 33.2%,and Cik<0.4 accounted for 45.5%.The overall Cik value is small and fluctuates greatly,the ecological niche separation exists among species,the utilization of resources tends to make up for each other,the population shares the community's environmental resources more fully,and the species in the community have a high degree of similarity in the utilization of resources.This type of natural forest near nature,maintain biodiversity and ecosystem stability,to establish a stable plant community and natural regeneration and seek the ideal mode of mixed tree species,keep the symbiosis between tree species,make full use of resources,environment is complementary,efficient use of resources,environment,to improve the comprehensive productivity of forest ecological system.