Impacts of Contaminants on the Ecological Role of Lotic Biofilms.
Biofilms play a fundamental ecological role in freshwater ecosystems as they contribute to ecosystem function(s) such as autotrophic primary production, organic matter decomposition and the bottom-up directed energy transfer in the food web. The present focused review summarizes the scientific knowledge on how the roles of autotrophic and heterotrophic biofilms can be modulated as a response to chemical (i.e., pesticide) stress. We discuss how horizontal effects (alterations in the structure of biofilms) can affect the physiological fitness and life history strategy of the next trophic level (vertical effects), namely primary consumers. Since the literature indicates that heterotrophic biofilms are currently at risk as a result of pesticide stress, the protectiveness of environmental risk assessment in Europe as well as North America is questioned. By briefly outlining substantial knowledge gaps, we provide ideas on how the identified uncertainties may be empirically addressed.
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07, Uppsala, Sweden. alexander.feckler@slu.se.
Alexander
A
Feckler
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07, Uppsala, Sweden.
Maria
M
Kahlert
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07, Uppsala, Sweden.|Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, 76829, Landau, Germany.
Mirco
M
Bundschuh
D018441:Biofilms / Q000187:drug effects*; D004463:Ecology; D017753:Ecosystem; D005060:Europe; D020387:Food Chain; D005618:Fresh Water / Q000737:chemistry / Q000382:microbiology*; D010575:Pesticides / Q000494:pharmacology*; D013312:Stress, Physiological; D014874:Water Pollutants, Chemical / Q000494:pharmacology*
D010575:Pesticides; D014874:Water Pollutants, Chemical
Ecosystem function; Indirect effects; Leaf litter breakdown; Microbial community composition; Trophic interaction