# The Community Matrix and the Number of Species in a Community

John H. Vandermeer
The American Naturalist
Vol. 104, No. 935 (Jan. - Feb., 1970), pp. 73-83
Stable URL: http://www.jstor.org/stable/2459074
Page Count: 11

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

Preview not available

## Abstract

In this paper I am concerned with the number of species that will be held in stable equilibrium in a community of competing organisms, using the general form of the Lotka-Volterra competition equations for m species. Defining Ki as the saturation density for the ith species and αij as the competition coefficient between species i and j, and Ni as the equilibrium density of species i, the number of species will be determined by N̄, K̄, $\overline{\alpha}$, var (K), the covariances among the α's, and the covariance between α and N. In particular, the number of species increases as K̄ increases but as N̄, $\overline{\alpha}$, cov (α), cov (α,N) and variance of K decrease.

• 73
• 74
• 75
• 76
• 77
• 78
• 79
• 80
• 81
• 82
• 83