Inter- and intra stream variation of lignicolous freshwater fungi in tropical Australia

Abstract

Freshwater ecosystems are in a constant interaction with the terrestrial environment (riparian) surrounding them. Riparian vegetation is the major source of organic input into the stream ecosystem, which includes woody debris. The impact of the type of riparian vegetation on the biodiversity of lignicolous freshwater fungi in five tropical streams of the Barron River catchment area in Atherton Tablelands, Queensland, Australia was investigated. The collection sites were broadly classified in three types based on the kind of riparian vegetation; pristine, re-growth and agricultural zones. Fifty wood samples collected from each of 12 sites yielded 162 fungal taxa. The dominant fungi were species of Annulatascus, Aquaticola (Annulatascaceae), Anthostomella (Xylariaceae), Massarina (Lophiostomataceae) and Savoryella (Sordariales incertae sedis). The highest species diversity was found in the pristine forest zone, followed by agricultural zone, while the re-growth zone was least diverse. Species overlap was seen between all streams, and between the three types of riparian vegetation. The fungal species showed little habitat recurrence, however major changes were observed in species richness and abundance, with varying degrees of human disturbance.