title: Can acid volatile sulfides (AVS) influence metal concentrations in the macrophyte Myriophyllum aquaticum?
abstract: The difference between the molar concentrations of simultaneously extracted metals (SEM) and acid volatile sulfides (AVS) is widely used to predict metal availability toward invertebrates in hypoxic sediments. However, this model is poorly investigated for macrophytes. The present study evaluates metal accumulation in roots and stems of the macrophyte Myriophyllum aquaticum during a 54 day lab experiment. The macrophytes, rooting in metal contaminated, hypoxic, and sulfide rich field sediments were exposed to surface water with 40% or 90% oxygen. High oxygen concentrations in the 90% treatment resulted in dissolution of the metal-sulfide complexes and a gradual increase in labile metal concentrations during the experiment. However, the general trend of increasing availability in the sediment with time was not translated in rising M. aquaticum metal concentrations. Processes at the root-sediment interface, e.g., radial oxygen loss (ROL) or the release of organic compounds by plant roots and their effect on metal availability in the rhizosphere may be of larger importance for metal accumulation than the bulk metal mobility predicted by the SEM-AVS model.
authors.affiliation: Department of Biology, Ecosystem Management Research Group, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium. johannes.teuchies@ua.ac.be
authors.forename: Johannes
authors.initials: J
authors.lastname: Teuchies
authors.forename: Maarten
authors.initials: M
authors.lastname: De Jonge
authors.forename: Patrick
authors.initials: P
authors.lastname: Meire
authors.forename: Ronny
authors.initials: R
authors.lastname: Blust
authors.forename: Lieven
authors.initials: L
authors.lastname: Bervoets
mesh_terms: D019684:Magnoliopsida / Q000737:chemistry*; D008670:Metals / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D014835:Volatilization
chemical_list: D008670:Metals; D013440:Sulfides