Truffle-like fungi sporocarps in a eucalypt-dominated landscape: patterns in diversity and community structure

Abstract

Truffle-like fungi are highly diverse yet poorly known in Australia. To assess the species richness, biomass, and community assemblages of truffle-like fungi in different habitats we sampled sporocarps of truffle-like fungi in three eucalypt-dominated forest types (grassy woodland, wet sclerophyll forest, and dry sclerophyll forest) once in summer and once in winter, at two sites (Mount Kaputar and New England) in northern New South Wales, Australia. One hundred and eighteen species in 35 genera were collected; over half (51.7 %) of the species were undescribed. Grassy woodland and wet forest communities had greater species richness and a lower standing crop than dry forest communities. Species richness and standing crop was greater in winter than in summer. Overall, species from the family Russulaceae, and the genera 'Dermocybe', 'Descomyces', and 'Hysterangium' were dominant. Community composition varied among forest types and each forest type exhibited a suite of unique and common species, although much variation was unexplained. Variation in community structure was associated with some habitat attributes; at Mount Kaputar, woody plant species richness, canopy cover, litter depth, soil phosphorous, and elevation helped explain the sporocarp communities of different forest types, while at New England, woody plant species richness, rainfall, topographic aspect, soil texture, and soil nitrogen helped explain communities. This work contributes to knowledge of truffle-like fungal diversity, the factors affecting sporocarp distribution across landscapes, and the availability of sporocarps as a food resource for mycophagous mammals. Greater understanding of fungal diversity and mammal-fungal interactions also has important implications for managing forest biodiversity.