Niche Characteristics of Shrub Dominant Population in Zengziyan of Jinfo Mountain, Nanchuan County

In this paper, the niche breadths and overlaps of 9 dominant species of shrub in Zengziyan of Jinfo Mountain are measured by using the formulas described by Levins, Hurlbert and Pianka, and the relationships among niche breadth, niche overlap and interspecific association are discussed. The results show that the niche breadths of main dominant species, the niche overlaps among the species with the same or similar environment requirements, and the overlaps between the species with broad niche breadth and other species are much large. The more intense the positive association of the interspecies, the larger the value of niche overlap is, and the more intense the negative association, the smaller the value of niche overlap is.