Surface ocean iron fertilization: The role of airborne volcanic ash from subduction zone and hot spot volcanoes and related iron fluxes into the Pacific Ocean
Por:
Olgun N., Duggen S., Croot P.L., Delmelle P., Dietze H., Schacht U., Óskarsson N., Siebe C., Auer A., Garbe-Schönberg D.
Publicada:
1 oct 2011
Resumen:
Surface ocean iron (Fe) fertilization can affect the marine primary productivity (MPP), thereby impacting on CO2 exchanges at the atmosphere-ocean interface and eventually on climate. Mineral (aeolian or desert) dust is known to be a major atmospheric source for the surface ocean biogeochemical iron cycle, but the significance of volcanic ash is poorly constrained. We present the results of geochemical experiments aimed at determining the rapid release of Fe upon contact of pristine volcanic ash with seawater, mimicking their dry deposition into the surface ocean. Our data show that volcanic ash from both subduction zone and hot spot volcanoes (n = 44 samples) rapidly mobilized significant amounts of soluble Fe into seawater (35-340 nmol/g ash), with a suggested global mean of 200 +/- 50 nmol Fe/g ash. These values are comparable to the range for desert dust in experiments at seawater pH (10-125 nmol Fe/g dust) presented in the literature (Guieu et al., 1996; Spokes et al., 1996). Comb
Filiaciones:
Olgun N.:
Dynamics of the Ocean Floor Division, Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany
Marine Biogeochemistry Division, Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Dusternbrooker Weg 20, Kiel D-24105, Germany
Duggen S.:
Dynamics of the Ocean Floor Division, Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany
A. P. Moller Skolen, Upper Secondary School, Sixth Form College of the Danish National Minority in Northern Germany, Fjordallee 1, Schleswig D-24837, Germany
Croot P.L.:
Marine Biogeochemistry Division, Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Dusternbrooker Weg 20, Kiel D-24105, Germany
Plymouth Marine Laboratory, Plymouth PL1 3DH, United Kingdom
Delmelle P.:
Environment Department, University of York, Heslington, York YO10 5D, United Kingdom
Dietze H.:
Marine Biogeochemistry Division, Leibniz-Institute of Marine Sciences, IFM-GEOMAR, Dusternbrooker Weg 20, Kiel D-24105, Germany
Schacht U.:
CO2CRC, Australian School of Petroleum, University of Adelaide, Gate 6, Frome Road, Adelaide SA 5005, Australia
Óskarsson N.:
Institute of Earth Sciences, University of Iceland, Askja, Sturlugata 7, Reykjavík 101, Iceland
Siebe C.:
Univ Nacl Autonoma Mexico, Inst Geofis, Dept Vulcanol, Coyoacan 04510, Mexico
Auer A.:
Department of Geology, University of Otago, PO Box 56, Dunedin 9054, New Zealand
Garbe-Schönberg D.:
Institute of Geosciences, Universtity of Kiel, Olshausenstrasse 40, Kiel D-24118, Germany
All Open Access, Bronze
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