title: Complexation of silver and dissolved organic matter in soil water extracts.
abstract: An important aspect of the behaviour and fate of silver (Ag) in soils is the interaction with dissolved organic matter (DOM). The complexation and strength of binding of Ag(+) with DOM in soil water extracts was examined and modelled based on a range of chemical and quality DOM measurements. Silver ion binding measured by addition of the (110m)Ag radioisotope in addition to a cation exchange resin technique were used to determine strongly complexed Ag in solutions. Silver was found to be up to 70% strongly complexed. The variability in Ag(+) binding by DOM across different soils was closely related (R(2) = 0.8) to the mid-infrared spectra of these extracts. The affinity of Ag(+) for DOM was stronger in solutions containing a greater content of humic and aromatic structures. The ability of Ag(+) to complex with DOM could result in increased mobilisation of this metal in the soil environment.
authors: Waite Research Institute, School of Agriculture, Food and Wine, University of Adelaide, Waite Rd, SA 5064, Australia. Electronic address: Lara.Settimio@adelaide.edu.au.
authors: Lara
authors: L
authors: Settimio
authors: Waite Research Institute, School of Agriculture, Food and Wine, University of Adelaide, Waite Rd, SA 5064, Australia; CSIRO Land and Water, Contaminant Chemistry and Ecotoxicology Program, Minerals Down Under Flagship, Waite Campus, Waite Rd, SA 5064, Australia.
authors: Mike J
authors: MJ
authors: McLaughlin
authors: CSIRO Land and Water, Contaminant Chemistry and Ecotoxicology Program, Minerals Down Under Flagship, Waite Campus, Waite Rd, SA 5064, Australia.
authors: Jason K
authors: JK
authors: Kirby
authors: CSIRO Land and Water, Contaminant Chemistry and Ecotoxicology Program, Minerals Down Under Flagship, Waite Campus, Waite Rd, SA 5064, Australia.
authors: Kate A
authors: KA
authors: Langdon
authors: CSIRO Land and Water, Contaminant Chemistry and Ecotoxicology Program, Minerals Down Under Flagship, Waite Campus, Waite Rd, SA 5064, Australia.
authors: Les
authors: L
authors: Janik
authors: Wilfrid Laurier University, Waterloo, ON, Canada.
authors: Scott
authors: S
authors: Smith
mesh_terms: D008670:Metals; D008956:Models, Chemical; D012834:Silver / Q000737:chemistry*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D012996:Solutions; D014867:Water / Q000737:chemistry*
chemical_list: D008670:Metals; D012987:Soil; D012989:Soil Pollutants; D012996:Solutions; D014867:Water; D012834:Silver
keywords: Complexation; Dissolved organic carbon; Silver; Soil; Spectroscopy