Community Structure of Wood-Decaying Basidiomycetes in Pasoh

Abstract

More than 200 species of polypores, the most important group of wooddecaying basidiomycetes have been found in Pasoh Forest Reserve (Pasoh FR), Malaysia. Among them, about 35 species are pantropical, 30 species are paleotropical and only 7 species are cosmopolitan or widespread in the Northern Hemisphere. Many of the others are probably tropical Asiatic species. We analyzed niche differentiation of wood-decaying basidiomycetes according to the diameter of the substrata. Among the common species in Pasoh FR, Coriolopsis retropicta, Microporus xanthopus etc., were restricted to small substrata such as fallen branches and twigs while Erythromyces crocicreas, Ganoderma australe etc., were found mostly on large substrata. Earliella scabrosa, Stereum ostrea etc., occurred on both large and small substrata. We examined host specificity and preference of wood-decaying basidiomycetes in Pasoh FR. Many species such as G. australe and Nigroporus vinosus occurred in various tree families, but some species were restricted to or were most frequently found in one or a few tree families. For example, Erythromyces crocicreas, Fomitopsis dochmia etc. were restricted to dipterocarp trees. We also examined the effects of decomposition stage of substrata on species of wood-decaying basidiomycetes. Some species such as G. australe, M. affinis etc. were mainly found on newly fallen trees while other species such asNigroporus vinosus, etc., were on well-decomposed trees. Species richness of wood-decaying basidiomycetes was higher in a primary forest plot than in a regenerating forest plot. This suggests that a low frequency of treefall in the regenerating forest reduced the species richness of wood-decaying basidiomycetes.