title: Ethanol and phenanthrene increase the biomass of fungal assemblages and decrease plant litter decomposition in streams.
abstract: Fungi, particularly aquatic hyphomycetes, have been recognized as playing a dominant role in microbial decomposition of plant litter in streams. In this study, we used a microcosm experiment with different levels of fungal diversity (species number and identity) using monocultures and combinations with up to five aquatic hyphomycete species (Articulospora tetracladia, Tricladium splendens, Heliscus submersus, Tetrachaetum elegans and Flagellospora curta) to assess the effects of ethanol and phenanthrene on three functional measures: plant litter decomposition, fungal biomass accrual and reproduction. Alder leaves were conditioned by fungi for 7days and then were exposed to phenanthrene (1mgL(-1)) dissolved in ethanol (0.1% final concentration) or ethanol (at the concentration used to solubilise phenanthrene) for further 24days. Exposure to ethanol alone or in combination with phenanthrene decreased leaf decomposition and fungal reproduction, but increased fungal biomass produced. All aspects of fungal activity varied with species number. Fungal activity in polycultures was generally higher than that expected from the sum of the weighted performances of participating species in monoculture, suggesting complementarity between species. However, the activity of fungi in polycultures did not exceed the activity of the most productive species either in the absence or presence of ethanol alone or with phenanthrene.
authors.affiliation: Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Diana
authors.initials: D
authors.lastname: Barros
authors.affiliation: Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Oliveira
authors.affiliation: Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Pascoal
authors.affiliation: Centre of Molecular and Environmental Biology (CBMA), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; Institute of Science and Innovation for Bio-Sustainability (IB-S), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. Electronic address: fcassio@bio.uminho.pt.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Cássio
mesh_terms: D029661:Alnus / Q000382:microbiology*; D018533:Biomass; D017753:Ecosystem; D000431:Ethanol / Q000009:adverse effects*; D005658:Fungi / Q000187:drug effects*; D003904:Mitosporic Fungi / Q000187:drug effects*; D010616:Phenanthrenes / Q000009:adverse effects*; D018515:Plant Leaves / Q000382:microbiology*; D045483:Rivers / Q000382:microbiology*
chemical_list: D010616:Phenanthrenes; D000431:Ethanol
keywords: Ecosystem function; Ethanol; Fungal consortia; Phenanthrene; Streams