贵州野核桃天然林主要树种生态位和种间关系研究

Ecological Niche and Interspecific Relationship of Main Tree Species in Natural Forest of Juglans cathayensis in Guizhou

选取分布集中、种群较大且原生性强的贵州野核桃天然林群落,采用生态位分析、方差比率法、χ^(2)检验、AC指数、Jaccard指数、Ochiai指数、Dice指数分析的方法,探明贵州野核桃群落20个主要树种生态位和种间联结特征及其相互关系。结果表明:(1)生态位宽度B_((SW)i)值比B_((L)j)值大,测度结果基本一致,群落中野核桃生态位宽度值最大,白檀生态位宽度值最小;重要值和生态位宽度值依次排前三的是野核桃、灯台树、漆树,他们构成了所处群落优势种或建群种;(2)贵州野核桃天然林主要树种利用资源的相似性程度和生态位重叠大多数种对都较小,种间竞争相对较弱,但青榨槭与主要树种资源利用相似性和重叠值都较大,其种间竞争最激烈;(3)生态位相似性比例值和生态位重叠值的对数分布不均,且小值的对数中数值最小(C_(ih)=0,α_(ih)=0),大值的对数中数值较大(C_(ih)=1,α_(ih)=0.89);(4)贵州野核桃天然林群落中主要树种总体关联性不显著,群落处于演替中期。贵州野核桃天然林群落中优势种群对环境资源的利用较强,种群伴生种少部分竞争相当激烈,大部分竞争相对较弱,野核桃幼树的更新状况较差,群落结构可能具有一定的不稳定性,本研究可为贵州野核桃的科学保护与合理开发利用提供理论依据。

The natural forest community of Juglans cathayensis in Guizhou Province with concentrated distribution,large population and strong original nature was selected,and ecological niche analysis,variance ratio method χ^(2) Test,AC index,Jaccard index,Ochiai index,and Dice index analysis methods were used to explore the ecological niche and interspecific association characteristics of 20 major tree species in the J.cathayensis community in Guizhou and their relationships.The results showed that:(1)The ecological niche width value of B_((SW)i) was larger than the value of B_((L)j),and the measurement results were basically the same.In the community,the ecological niche width value of J.cathayensis were the largest,and the ecological niche width value of Symplocos paniculata was the smallest;The top three in terms of important value and ecological niche width value were J.cathayensis,Cornus contorsa,and Toxicodendron vernicifluum,which constitute the dominant species or constructive species of the community;(2)The similarity and niche overlap of the utilization resources of the main tree species were mostly small,and the interspecific competition was relatively weak.However,the similarity and overlap of the utilization resources of Acer davidii and the main tree species were large,and the interspecific competition was the most intense;(3)The logarithmic distribution of ecological niche similarity ratio value and ecological niche overlap value was uneven,the logarithmic value of small value was the smallest(C_( ih)=0,α_(ih)=0),and the logarithm of the larger value had a larger median value(C_( ih)=1,α_(ih)=0.89);(4)The overall correlation of the main tree species in the natural forest community of J.cathayensis in Guizhou was not significant,and the community was in the middle stage of succession.The dominant population in the natural forest community of J.cathayensis in Guizhou had a strong utilization of environmental resources.The competition among a small number of accompanying species was quite fierce,while the competition among most was relatively weak.The regeneration status of young trees of J.cathayensis was poor,and the community structure might have some instability.This study can provide a theoretical basis for the scientific protection and rational development and utilization of J.cathayensis in Guizhou.