Fungi in liverwort-based biocrust

Fungal distribution in a liverwort-based biocrust was examined at different depths (0, 5 and 20 mm) by direct counting using both light and fluorescence microscopy. The DNA-based taxonomic composition of fungi was also determined and differences between depths (above and below 5 mm) were assessed. The fungal biomass was greatest at the surface where large hyphae, sporangia and fungi within plants were more abundant than at 5 mm and 20 mm depth. The texture of the biocrust also differed significantly with depth. Likewise, the analysis of microbial DNA composition revealed a difference between depths, both for the amount of total fungi and of each phylum where the total amount of fungi was highest above 5 mm. Ascomycota fungi were dominant both below 5 mm and near the surface where both their amount and proportion were substantially higher than deeper down. The dark septate Exophiala, Phialocephala and Pseudogymnoascus were the most abundant genera.