Biolabile ferrous iron bearing nanoparticles in glacial sediments
| Autor: | Robert Raiswell, Jon R. Hawkings, Jemma L. Wadham, Majid Kazemian Abyaneh, Liane G. Benning, Anthony Stockdale, Tohru Araki, Burkhard Kaulich, Martyn Tranter, Monika Koch-Müller |
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| Rok vydání: | 2018 |
| Předmět: |
010504 meteorology & atmospheric sciences
Greenland ice sheet 010502 geochemistry & geophysics 01 natural sciences Arctic iron Geochemistry and Petrology Earth and Planetary Sciences (miscellaneous) 14. Life underwater Glacial period 0105 earth and related environmental sciences geography geography.geographical_feature_category Glacier Particulates export-productivity Iceberg Geophysics sediment 13. Climate action Space and Planetary Science Environmental chemistry glaciers Aeolian processes Ice sheet biological pump Geology |
| Zdroj: | Earth and Planetary Science Letters Hawkings, J R, Benning, L G, Raiswell, R, Kaulich, B, Araki, T, Abyaneh, M, Stockdale, A, Koch-Müller, M, Wadham, J L & Tranter, M 2018, ' Biolabile ferrous iron bearing nanoparticles in glacial sediments ', Earth and Planetary Science Letters, vol. 493, pp. 92-101 . https://doi.org/10.1016/j.epsl.2018.04.022 |
| ISSN: | 0012-821X 1385-013X |
| Popis: | Glaciers and ice sheets are a significant source of nanoparticulate Fe, which is potentially important in sustaining the high productivity observed in the near-coastal regions proximal to terrestrial ice cover. However, the bioavailability of particulate iron is poorly understood, despite its importance in the ocean Fe inventory. We combined high-resolution imaging and spectroscopy to investigate the abundance, morphology and valence state of particulate iron in glacial sediments. Our results document the widespread occurrence of amorphous and Fe(II)-rich and Fe(II)-bearing nanoparticles in Arctic glacial meltwaters and iceberg debris, compared to Fe(III)-rich dominated particulates in an aeolian dust sample. Fe(II) is thought to be highly biolabile in marine environments. Our work shows that glacially derived Fe is more labile than previously assumed, and consequently that glaciers and ice sheets are therefore able to export potentially bioavailable Fe(II)-containing nanoparticulate material to downstream ecosystems, including those in a marine setting. Our findings provide further evidence that Greenland Ice Sheet meltwaters may provide biolabile particulate Fe that may fuel the large summer phytoplankton bloom in the Labrador Sea, and that Fe(II)-rich particulates from a region of very high productivity downstream of a polar ice sheet may be glacial in origin. |
| Databáze: | OpenAIRE |
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