title: Natural wetland emissions of methylated trace elements.
abstract: Natural wetlands are well known for their significant methane emissions. However, trace element emissions via biomethylation and subsequent volatilization from pristine wetlands are virtually unstudied, even though wetlands constitute large reservoirs for trace elements. Here we show that the average volatile fluxes of selenium (<0.12 μg m(-2) day(-1)), sulphur (<37 μg m(-2) day(-1)) and arsenic (<0.54 μg m(-2) day(-1)) from a pristine peatland are considerable and consistent over two summers. We compare these fluxes with the total concentrations in the peat and show that selenium is up to 40 times more efficiently volatilized than arsenic, and over 100 times more efficiently volatilized than sulphur. We further show that the volatilization of selenium and arsenic increases with temperature, implying that emissions of these health-relevant trace elements will increase with global warming. We suggest that biomethylation and volatilization in wetlands play a crucial role in the mobilization and global biogeochemical cycling of trace elements.
authors.affiliation: 1] Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland [2] Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich CH-8092, Switzerland.
authors.forename: Bas
authors.initials: B
authors.lastname: Vriens
authors.affiliation: 1] University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, Muttenz CH-4132, Switzerland [2] Department of Environmental Technology, Wageningen University, Wageningen 6708 WG, The Netherlands.
authors.forename: Markus
authors.initials: M
authors.lastname: Lenz
authors.affiliation: Earth Science Institute (ISTerre), University of Grenoble-I, Grenoble F-38041, France and Institut Universitaire de France, Paris 75005, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Charlet
authors.affiliation: Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Berg
authors.affiliation: 1] Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf CH-8600, Switzerland [2] Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich CH-8092, Switzerland.
authors.forename: Lenny H E
authors.initials: LH
authors.lastname: Winkel
mesh_terms: D001151:Arsenic / Q000032:analysis*; D057232:Global Warming; D008745:Methylation; D012643:Selenium / Q000032:analysis*; D013455:Sulfur / Q000032:analysis*; D013557:Switzerland; D013696:Temperature; D014131:Trace Elements / Q000032:analysis*; D014835:Volatilization; D053833:Wetlands
chemical_list: D014131:Trace Elements; D013455:Sulfur; D012643:Selenium; D001151:Arsenic