title: Effect of Ocean Acidification on Organic and Inorganic Speciation of Trace Metals.
abstract: Rising concentrations of atmospheric carbon dioxide are causing acidification of the oceans. This results in changes to the concentrations of key chemical species such as hydroxide, carbonate and bicarbonate ions. These changes will affect the distribution of different forms of trace metals. Using IPCC data for pCO2 and pH under four future emissions scenarios (to the year 2100) we use a chemical speciation model to predict changes in the distribution of organic and inorganic forms of trace metals. Under a scenario where emissions peak after the year 2100, predicted free ion Al, Fe, Cu, and Pb concentrations increase by factors of up to approximately 21, 2.4, 1.5, and 2.0 respectively. Concentrations of organically complexed metal typically have a lower sensitivity to ocean acidification induced changes. Concentrations of organically complexed Mn, Cu, Zn, and Cd fall by up to 10%, while those of organically complexed Fe, Co, and Ni rise by up to 14%. Although modest, these changes may have significance for the biological availability of metals given the close adaptation of marine microorganisms to their environment.
authors.affiliation: School of Earth and Environment, University of Leeds , Leeds, LS2 9JT, U.K.
authors.forename: Anthony
authors.initials: A
authors.lastname: Stockdale
authors.affiliation: Centre for Ecology and Hydrology, Lancaster Environment Centre , Lancaster, LA1 4AP, U.K.
authors.forename: Edward
authors.initials: E
authors.lastname: Tipping
authors.affiliation: Centre for Ecology and Hydrology, Lancaster Environment Centre , Lancaster, LA1 4AP, U.K.
authors.forename: Stephen
authors.initials: S
authors.lastname: Lofts
authors.affiliation: School of Animal, Rural and Environmental Sciences, Nottingham Trent University , Brackenhurst Campus, Southwell, Nottinghamshire NG25 0QF, U.K.
authors.forename: Robert J G
authors.initials: RJ
authors.lastname: Mortimer
mesh_terms: D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry* / Q000145:classification; D009792:Oceans and Seas; D012623:Seawater / Q000737:chemistry*; D014131:Trace Elements; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D008670:Metals; D014131:Trace Elements; D014874:Water Pollutants, Chemical