Diversity patterns of leaf-associated aquatic hyphomycetes along a broad latitudinal gradient

• Published in: Fungal Ecology
• Main Authors: Jabiol, Jérémy, Bruder, Andreas, Gessner, Mark O., Makkonen, Marika, McKie, Brendan G., Peeters, Edwin T.H.M., Vos, Veronique C. A., Chauvet, Eric
• Other Authors: Leibniz-Institut für Gewässerökologie und Binnenfischerei - IGB (GERMANY), Institut National Polytechnique de Toulouse - INPT (FRANCE), Technische Universität Berlin - TU Berlin (GERMANY), Umea University (SWEDEN), Université Toulouse III - Paul Sabatier - UPS (FRANCE), Wageningen University & Research - WUR (NETHERLANDS), Swiss Federal Institute of Aquatic Science and Technology - EAWAG (SWITZERLAND), Sveriges lantbruksuniversitet - SLU (SWEDEN), Eidgenössische Technische Hochschule Zürich - ETHZ (SWITZERLAND), Vrije University Amsterdam - VU (NETHERLANDS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier 2013
• Subjects: Biodiversité et Ecologie; Aquatic hyphomycetes; Fungal biodiversity; Fungal sporulation; Invertebrate consumers; Latitudinal gradient; Plant litter; Species richness; Subarctic
• Online Access: http://oatao.univ-toulouse.fr/11089/; http://oatao.univ-toulouse.fr/11089/1/jabiol_11089.pdf; https://doi.org/10.1016/j.funeco.2013.04.002

Information about the global distribution of aquatic hyphomycetes is scarce, despite the primary importance of these fungi in stream ecosystem functioning. In particular, the relationship between their diversity and latitude remains unclear, due to a lack of coor- dinated surveys across broad latitudinal ranges. This study is a first report on latitudinal patterns of aquatic hyphomycete diversity associated with native leaf-litter species in five streams located along a gradient extending from the subarctic to the tropics. Exposure of leaf litter in mesh bags of three different mesh sizes facilitated assessing the effects of including or excluding different size-classes of litter-consuming invertebrates. Aquatic hyphomycete evenness was notably constant across all sites, whereas species richness and diversity, expressed as the Hill number, reached a maximum at mid-latitudes (Medi- terranean and temperate streams). These latitudinal patterns were consistent across litter species, despite a notable influence of litter identity on fungal communities at the local scale. As a result, the bell-shaped distribution of species richness and Hill diversity devi- ated markedly from the latitudinal patterns of most other groups of organisms. Differences in the body-size distribution of invertebrate communities colonizing the leaves had no effect on aquatic hyphomycete species richness, Hill diversity or evenness, but inverte- brates could still influence fungal communities by depleting litter, an effect that was not captured by the design of our experiment.