小陇山国家级自然保护区油松群落生态位研究

The niche of dominant species populations in Pinus tabulaeformis forest in Xiaolong Mountain National Nature Reserve

文中采用样方调查法,对研究区内油松群落中主要种群的Shannon-Weinner多样性指标及Lev-ins生态位宽度、生态位重叠值和生态位相似比例等进行了分析。结果表明:1)油松群落中油松的生态位宽度最大为0.9827,槲树的生态位宽度最小为0.1582;2)优势种油松与其他物种的生态位重叠值在0.06～0.1之间,反之在0.01～0.05之间,说明油松群落的生态位重叠值不大,群落中因利用相同的资源位而产生的种间竞争并不激烈,是一个稳定的森林群落;3)生态位相似比例大于0.5的有9对,占20%,其物种间生态位相似比例值一般较低,反映其主要物种利用资源的相似程度较小。但是生态位宽度较大的物种之间的生态位相似性比例仍较高,如油松与甘肃山楂、锐齿栎的生态位相似性比例分别为0.5209、0.5320。

In this paper the niche of the main tree populations in Pinus tabulaeformis forest in Xiaolong Mountain National Nature Reserve were measured using the formulas of the Shannon-Weinner and Levins niche breadth,niche similarity and niche overlap by sampling method.The results showed：1）The niche breadth of Pinus tabulaeformis Carr is the biggest,its niche breadth is 0.9827;the niche breadth of Quercus dentata Thunb is the smallest,its niche breadth is 0.1582.2）The niche overlap between the Pinus tabulaeformis Carr and other species is 0.06 to 0.1,whereas is 0.01 to 0.05,Therefore,small niche overlap degree found in this study suggests less fierce interspecies competition in the forest,representing a stable community of the Pinus tabulaeformis Carr forest.3）There are 9 sets of niche overlap values greater than 0.5,accounting for 20% of the total.The niche similarity among the species is generally lower,which shows that the main species are low in similarity of resource utilization.But the niche overlaps among the species with broad niche breadths are much greater,as shown between Pinus tabulaeformis Carr and Crataegus kansuensis,between Pinus tabulaeformis Carr and Quercus acutidentata,smiilarity values being 0.5209 and 0.5320,respectively.