濒危植物单性木兰群落优势种群生态位研究

Research on the niche of dominant species population of endangered plants Kmeria septentrionalis community

以分布样地类型作为一维资源位,应用Levins、Hurlbert生态位宽度公式和Pianka生态位重叠以及生态位相似比例公式对单性木兰乔木层14个群落优势种群的生态位特征分析。结果表明:(1)单性木兰具有最大位宽度,对环境资源的利用具有明显优势,是群落中的建群种;(2)生态位宽的种群可能产生较小的生态位重叠,生态位较窄的种群间也会产生较大的生态位重叠,这主要取决于物种的生物学特性和对环境资源的需求;(3)单性木兰分布地的坡向、基岩裸露度、坡度等因子是影响单性木兰分布的重要因子。

As distribution plots to be one-dimensional resource-niche,niche breadth formula of levins,Hurlbert,niche overlap index and niche similarity proportion were used to analyze niche characteristics of Kmeria septentrionalis community sampled from 14 populations in Mulun National Nature Reserve,Guangxi.The results were as follows：（1）K.septentrionalis was dominant species because this species had the largest niche breadths and obvious advantage of environment resource utilization;（2）Niche overlap index was depent upon species＇s biological characteristics and requested of environmental resouces because niche overlap was lower among high value niche populations or were higher among low value niche populations;（3）Some important environment factors such as slope-exposure,the naking of bed rock,and grade of slope were the key factors that influenced the distribution status of K.septentrionalis.