Distribution and ecology of Myxomycetes in temperate forests. I. Patterns of occurrence in the upland forests of southwestern Virginia

Abstract

A comparative ecological study of the Myxomycetes occurring in five different upland forest communities in the Mountain Lake area of southwestern Virginia was carried out during 1982–1986. Although the forest communities selected for study occupied different relative positions (from subxeric to mesic) with respect to an environmental moisture complex-gradient, a high degree of similarity existed among the communities for species composition of Myxomycetes. However, absolute abundance, species richness, and species diversity were higher for the more mesic communities. The seasonal pattern was for both species richness and species diversity to be exceedingly low early in the season, to increase to their highest levels in August, and then to decline throughout the remainder of the season. In general, Myxomycetes appear to be rather opportunistic organisms, occupying those microhabitats suitable for their growth and development as these become available to them. Nevertheless, considerable resource partitioning among species would seem to exist, since characteristic patterns of microhabitat occupation and sporulation phenology were noted for most species. In an effort to quantify resource partitioning, values of niche breadth and niche overlap were calculated for 39 quantitatively important species.