title: Assessing the influence of compost and biochar amendments on the mobility and toxicity of metals and arsenic in a naturally contaminated mine soil.
abstract: Amending contaminated soils with organic wastes can influence trace element mobility and toxicity. Soluble concentrations of metals and arsenic were measured in pore water and aqueous soil extracts following the amendment of a heavily contaminated mine soil with compost and biochar (10% v:v) in a pot experiment. Speciation modelling and toxicity assays (Vibrio fischeri luminescence inhibition and Lolium perenne germination) were performed to discriminate mechanisms controlling metal mobility and assess toxicity risk thereafter. Biochar reduced free metal concentrations furthest but dissolved organic carbon primarily controlled metal mobility after compost amendment. Individually, both amendments induced considerable solubilisation of arsenic to pore water (>2500 μg l(-1)) related to pH and soluble phosphate but combining amendments most effectively reduced toxicity due to simultaneous reductions in extractable metals and increases in soluble nutrients (P). Thus the measure-monitor-model approach taken determined that combining the amendments was most effective at mitigating attendant toxicity risk.
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK. Electronic address: luke.beesley@hutton.ac.uk.
authors.forename: Luke
authors.initials: L
authors.lastname: Beesley
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK.
authors.forename: Onyeka S
authors.initials: OS
authors.lastname: Inneh
authors.affiliation: Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK.
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Norton
authors.affiliation: Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Moreno-Jimenez
authors.affiliation: CEBAS-CSIC, PO Box 164, 30100 Espinardo, Murcia, Spain.
authors.forename: Tania
authors.initials: T
authors.lastname: Pardo
authors.affiliation: CEBAS-CSIC, PO Box 164, 30100 Espinardo, Murcia, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Clemente
authors.affiliation: The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH, UK.
authors.forename: Julian J C
authors.initials: JJ
authors.lastname: Dawson
mesh_terms: D001151:Arsenic / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity; D002606:Charcoal / Q000737:chemistry*; D004787:Environmental Pollution; D052918:Environmental Restoration and Remediation / Q000379:methods; D018525:Germination / Q000187:drug effects; D008129:Lolium / Q000187:drug effects; D008670:Metals / Q000032:analysis / Q000737:chemistry*; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity
chemical_list: D008670:Metals; D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; D001151:Arsenic
keywords: Organic amendments; Pore water; Soil contamination; Speciation; Trace elements