Ecology of lignicolous myxomycetes in Brazilian Atlantic rain forest

This work describes ecological aspects of tropical lignicolous myxomycetes. The occurrence of lignicolous myxomycetes was related to wood pH, hardness, water absorption capacity, diameter, decay stage, soil contact, shading and moss cover of the logs, air temperature, and precipitation. To obtain data, 61-day excursions covering five Atlantic rain forest (lowland dense ombrophilous forest) fragments were carried out in Pernambuco State, Brazil. Eighty-four logs were exhaustively analyzed, and 272 myxomycetes specimens recorded. Two multivariate analyses and two correlational approaches were used to determine the relationship between lignicolous myxomycetes distribution and both wood and meteorological variables, the results of which indicated that the pH is the most important variable affecting myxomycete occurrence, followed by the decay stage. Wood acidity limits which species can live on a specific log, and the decay stage affects a group of variables related to moisture, which are affected as decay progress. All variables measured and how they may affect the occurrence of myxomycetes species are discussed.