Phosphorus burial in vivianite-type minerals in methane-rich coastal sediments
(2021) In Marine Chemistry 231.- Abstract
Sediments are a key sink for phosphorus (P) in coastal systems. This allows coastal areas to act as a filter for P that is transported from land to sea. Recent work suggests that vivianite-type ferrous iron (Fe(II))-P minerals may be more important as a sink for P in coastal sediments than previously thought. Here, we investigate the occurrence of such vivianite-type minerals in sediments of three eutrophic coastal sites with contrasting dynamics with respect to iron (Fe) and sulfur (S), covering a salinity range of 0 to 7. We only find authigenic vivianite-type minerals at the low and intermediate salinity sites, where Fe is available in excess over sulfide production. Sequential extractions combined with SEM-EDS and μXRF analysis... (More)
Sediments are a key sink for phosphorus (P) in coastal systems. This allows coastal areas to act as a filter for P that is transported from land to sea. Recent work suggests that vivianite-type ferrous iron (Fe(II))-P minerals may be more important as a sink for P in coastal sediments than previously thought. Here, we investigate the occurrence of such vivianite-type minerals in sediments of three eutrophic coastal sites with contrasting dynamics with respect to iron (Fe) and sulfur (S), covering a salinity range of 0 to 7. We only find authigenic vivianite-type minerals at the low and intermediate salinity sites, where Fe is available in excess over sulfide production. Sequential extractions combined with SEM-EDS and μXRF analysis point towards substitution of Fe in vivianite-type minerals by other transition metal cations such as magnesium and manganese, suggesting potentially different formation pathways modulated by metal cation availability. Our results suggest that vivianite-type minerals may act as a key sink for P in sediments of many other brackish coastal systems. Climate change-driven modulations of coastal bottom water salinity, and hence, Fe versus S availability in the sediment, may alter the role of vivianite-type minerals as a P burial sink over the coming decades. Model projections for the Baltic Sea point towards increased river input and freshening of coastal waters, which could enhance P burial. In contrast, sea level rise in the Chesapeake Bay area is expected to lead to an increase in bottom water salinity and this could lower rates of P burial or even liberate currently buried P, thereby enhancing eutrophication.
(Less)
- author
- Kubeneck, L. Joëlle ; Lenstra, Wytze K. ; Malkin, Sairah Y. ; Conley, Daniel J. LU and Slomp, Caroline P.
- organization
- publishing date
- 2021-04
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Iron, Phosphorus cycle, Sediments, Vivianite
- in
- Marine Chemistry
- volume
- 231
- article number
- 103948
- publisher
- Elsevier
- external identifiers
-
- scopus:85101164675
- ISSN
- 0304-4203
- DOI
- 10.1016/j.marchem.2021.103948
- language
- English
- LU publication?
- yes
- id
- c6483195-58bf-4324-9314-e4b8b655cc6b
- date added to LUP
- 2021-12-23 08:21:43
- date last changed
- 2023-02-21 10:20:19
@article{c6483195-58bf-4324-9314-e4b8b655cc6b,
abstract = {{<p>Sediments are a key sink for phosphorus (P) in coastal systems. This allows coastal areas to act as a filter for P that is transported from land to sea. Recent work suggests that vivianite-type ferrous iron (Fe(II))-P minerals may be more important as a sink for P in coastal sediments than previously thought. Here, we investigate the occurrence of such vivianite-type minerals in sediments of three eutrophic coastal sites with contrasting dynamics with respect to iron (Fe) and sulfur (S), covering a salinity range of 0 to 7. We only find authigenic vivianite-type minerals at the low and intermediate salinity sites, where Fe is available in excess over sulfide production. Sequential extractions combined with SEM-EDS and μXRF analysis point towards substitution of Fe in vivianite-type minerals by other transition metal cations such as magnesium and manganese, suggesting potentially different formation pathways modulated by metal cation availability. Our results suggest that vivianite-type minerals may act as a key sink for P in sediments of many other brackish coastal systems. Climate change-driven modulations of coastal bottom water salinity, and hence, Fe versus S availability in the sediment, may alter the role of vivianite-type minerals as a P burial sink over the coming decades. Model projections for the Baltic Sea point towards increased river input and freshening of coastal waters, which could enhance P burial. In contrast, sea level rise in the Chesapeake Bay area is expected to lead to an increase in bottom water salinity and this could lower rates of P burial or even liberate currently buried P, thereby enhancing eutrophication.</p>}},
author = {{Kubeneck, L. Joëlle and Lenstra, Wytze K. and Malkin, Sairah Y. and Conley, Daniel J. and Slomp, Caroline P.}},
issn = {{0304-4203}},
keywords = {{Iron; Phosphorus cycle; Sediments; Vivianite}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Marine Chemistry}},
title = {{Phosphorus burial in vivianite-type minerals in methane-rich coastal sediments}},
url = {{http://dx.doi.org/10.1016/j.marchem.2021.103948}},
doi = {{10.1016/j.marchem.2021.103948}},
volume = {{231}},
year = {{2021}},
}