Husdon-Edwards, KA, Bristow, CS, Cibin, G et al. (2 more authors) (2014) Solid-phase phosphorus speciation in Saharan Bodele Depression dusts and source sediments. Chemical Geology, 384. 16 - 26. ISSN 0009-2541
Abstract
Phosphorus (P) is one of the most important limiting nutrients for the growth of oceanic phytoplankton and terrestrial ecosystems, which in turn contributes to CO2 sequestration. The solid-phase speciation of P will influence its solubility and hence its availability to such ecosystems. This study reports on the results of X-ray diffraction, electron microprobe chemical analysis and X-ray mapping, chemical extractions and X-ray absorption near-edge spectroscopy analysis carried out to determine the solid-phase speciation of P in dusts and their source sediments from the Saharan Bodélé Depression, the world's greatest single source of dust. Chemical extraction data suggest that the Bodélé dusts contain 28 to 60% (mean 49%) P sorbed to, or co-precipitated with, Fe (hydr)oxides, < 10% organic P, 21–50% (mean 32%) detrital apatite P, and 10–22% (mean 15%) authigenic–biogenic apatite P. This is confirmed by the other analyses, which also suggest that the authigenic–biogenic apatite P is likely fish bone and scale, and that this might form a larger proportion of the apatite pool (33 +/− 22%) than given by the extraction data. This is the first-ever report of fish material in aeolian dust, and it is significant because P derived from fish bone and scale is relatively soluble and is often used as a soil fertilizer. Therefore, the fish-P will likely be the most readily consumed form of Bodélé P during soil weathering and atmospheric processing, but given time and acid dissolution, the detrital apatite, Fe-P and organic-P will also be made available. The Bodélé dust input of P to global ecosystems will only have a limited life, however, because its major source materials, diatomite in the Bodélé Depression, undergo persistent deflation and have a finite thickness.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/3.0/). |
Keywords: | Bodélé Depression; Sahara; Dust; Phosphorus; Fish; Apatite |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 18 Aug 2014 09:13 |
Last Modified: | 07 Dec 2022 15:31 |
Published Version: | http://dx.doi.org/10.1016/j.chemgeo.2014.06.014 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.chemgeo.2014.06.014 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:80012 |