河南小秦岭自然保护区木本植物优势种群的生态位特征

The niche characteristics of dominant woody plants population in Xiaoqinling Nature Reserve of Henan

通过生态位宽度、生态位重叠和生态位相似比例等指数对小秦岭自然保护区的2个1 hm2样地内各种木本植物种群进行了研究。结果表明:(1)乔木的生态位宽度并不一定大于灌木的生态位宽度,灌木可能有更强的环境适应能力;(2)重要值较小的物种可能有较大的生态位宽度,在取样面积不足时会影响研究结果的准确性;(3)不论生态位宽度的大小,物种均会有较大的生态位相似性比例以及生态位重叠,但生态位宽度较大的物种与更多的物种有较大的生态位相似性比例以及生态位重叠;(4)生态位相似性比例与生态位重叠的结果相似,但不尽相同,它们之间的差异表明物种利用相似的资源并不足以引起竞争。

On the basis of field investigation, the Levins and Shannon-Wiener niche breadth,niche overlap and niche similarity proportion were used to study the niche characteristics of all kinds of woody plants in two 1 hm^2 plots in Xiaoqinling Natural Reserve, Henan. The results showed that： （ 1 ） The niche breadth of trees is not necessarily greater than that of the shrubs, and shrubs may have stronger capability to adapt to the environment. （2） The species which have a less important value may have a bigger niche breadth,so the insufficient study area will affect the accuracy of the results. （3） Regard- less of the size of the niche breadth,all the species may have larger niche similarity proportion and larger niche overlap with other species, but the species which have a bigger niche breadth may have larger niche similarity proportion and larger niche overlap with more species. （4） The result of niche similarity proportion and niche overlap are similar but not the same, and the differences between them suggest that using the similar resources are not sufficient to cause competition among these species.