Fungos poróides (Agaricomycetes) na Floresta Nacional de Caxiuanã: fenologia e relação com o substrato, topografia e fatores micrometeorológicos

Abstract

This study was conducted in one of the sites of Amazon Biodiversity Program (PPBio) located in the Caxiuanã National Forest (PA) and aimed to present the poroid fungi with emphasis on new record, analyze the relationship of these fungi with the woody substrate and to examine the association between micrometeorological variables (air temperature, relative humidity and rainfall) for one year, in relation to environmental variables, produced by topography, with richness, density, and phenology of these fungi. Were identified 76 species of poroid fungi, distributed in 27 genera and 5 families. The species Cerrena sclerodepsis, Phellinus dependens and Trametes pavonia represent the first records for the Pará state. Microporellus iguazuensis is mentioned for the first time in Brazil and presents the proposal of a new species to science, called Microporellus hirsuta. Most of the species was considered rare and showed preference for substrates in the early decomposition stages. The number of occurrences of basidiomata and fungi species was higher on the stem of the families plants Caesalpinaceae, Sapotaceae, Annonaceae, Mimosaceae and Lecythidaceae, respectively, and at substrate with a smaller diameter. It was expected that differences in microclimate generated by different altitudes, in a short topographic gradient, were sufficient to generate differences in the poroid fungal community. However, although it was found a greater number of species in a region called the intermediate, this difference was not significant. The largest number of individuals was found in the first rains and the richness is positively correlated with rainfall. The activity index of basidioma production of the abundant species was higher during the first rains after the dry period. This study represents an advance in understanding the relationships of the fungi with the environment in which they grow, mainly in tropical regions, but many studies still need to be developed to clarify these relationships.