Patterns of distribution of microfungi in decomposing bog and fen plants

Abstract

The microfungal assemblages from the litter of the dominant vegetation of a forested bog and a riverine, sedge-dominated fen in southern boreal Alberta, Canada, were investigated over a 2-year period. Canonical correspondence analyses showed distinctly different fungal communities associated with litter of the dominant plant species of this bog (Sphagnum fuscum (Schimp.) Klinggr.) and fen (Carex aquatilis Wahlenb. leaves and rhizomes and Salix planifolia Pursh leaves and roots). Plant tissue quality variables, including total phosphorus and total nitrogen tissue concentrations, correlated most strongly with the fungal communities. In contrast, site-specific environmental (surface water chemical variables) and physical (peat and water temperatures, water level) variables were not correlated with the fungal communities of these five decomposing fen and bog plant litters. Of 93 identified fungal taxa, 25% occurred exclusively in the bog and 56% occurred exclusively in the fen. Eighteen species (19%) were common to the materials examined from both peatlands. Several species of (i) Aspergillus, Mortierella, and Oidiodendron were restricted to the Sphagnum litter in the bog, and species of (ii) Phialophora, Phialocephala, Fusarium, Dimorphospora foliicola, Monocillium constrictum, and several basidiomycetes were restricted to the Carex and Salix plant litters in the fen. These taxa constitute components of the bog and fen fungal communities, respectively.Key words: fungal communities, decomposition, bog, fen, canonical correspondence analysis (CCA).