Wood-inhabiting macrofungi Hymenochaetales and Polyporales (Basidiomycota) in the Amazon Forest: relationship the abiotic factors and substrate colonization.

Abstract

Hymenochaetales and Polyporales are important macrofungi for the maintenance of tropical forests, since they act directly in the nutrient cycling of the wood decomposition. In the Amazon, the largest tropical forest in the world, knowledge about Agaricomycetes is still insipient, since many areas have not yet been inventoried and new records appear each new study. To increase ecological knowledge about the Hymenochaetales and Polyporales, in the Brazilian Amazon region, collections were conducted in western Pará, Brazil, relating these fungi to the substrate they colonize and to environmental variables. 91 species were identified, with greater macrofungi richness associated with the rainy season; these fungi showed preferences for dead woods, of small diameter (class 1 = 5,9 ˫ 39 cm) and, in stages of decomposition still rigid or intermediate. The abundance and richness of Hymenochaetales and Polyporales were influenced by air humidity and the assemblage composition was influenced by temperature, air humidity and rainfall. The results indicate a rich diversity for western Pará region, these species are associated with environmental conditions, and may be threatened by the increasing pressure of human activity in the Brazilian Amazon.