Cadmium and phosphate in coastal Antarctic seawater : implications for Southern Ocean nutrient cycling
Hendry, Katharine R.
Rickaby, Rosalind E. M.
de Hoog, Jan C. M.
MetadataShow full item record
Cadmium is a biologically important trace metal that co-varies with phosphate (PO43- or Dissolved Inorganic Phosphate, DIP) in seawater. However, the exact nature of Cd uptake mechanisms and the relationship with phosphate and other nutrients in global oceans remains elusive. Here, we present a time series study of Cd and PO43- from coastal Antarctic seawater, showing that Cd co-varies with macronutrients during times of high biological activity even under nutrient and trace metal replete conditions. Our data imply that Cd/PO43- in coastal surface Antarctic seawater is higher than open ocean areas. Furthermore, the sinking of some proportion of this high Cd/PO43- water into Antarctic Bottom Water, followed by mixing into Circumpolar Deep Water, impacts Southern Ocean preformed nutrient and trace metal composition. A simple model of endmember water mass mixing with a particle fractionation of Cd/P (αCd-P) determined by the local environment can be used to account for the Cd/PO43- relationship in different parts of the ocean. The high Cd/PO43- of the coastal water is a consequence of two factors: the high input from terrestrial and continental shelf sediments and changes in biological fractionation with respect to P during uptake of Cd in regions of high Fe and Zn. This implies that the Cd/PO43- ratio of the Southern Ocean will vary on glacial-interglacial timescales as the proportion of deep water originating on the continental shelves of the Weddell Sea is reduced during glaciations because the ice shelf is pinned at the edge of the continental shelf. There could also be variations in biological fractionation of Cd/P in the surface waters of the Southern Ocean on these timescales as a result of changes in atmospheric inputs of trace metals. Further variations in the relationship between Cd and PO43- in seawater arise from changes in population structure and community requirements for macro- and micronutrients.
Author Posting. © The Author(s), 2008. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Chemistry 112 (2008): 149-157, doi:10.1016/j.marchem.2008.09.004.
Suggested CitationPreprint: Hendry, Katharine R., Rickaby, Rosalind E. M., de Hoog, Jan C. M., Weston, Keith, Rehkamper, Mark, "Cadmium and phosphate in coastal Antarctic seawater : implications for Southern Ocean nutrient cycling", 2008-09, https://doi.org/10.1016/j.marchem.2008.09.004, https://hdl.handle.net/1912/4822
Showing items related by title, author, creator and subject.
Proteomic responses of oceanic Synechococcus WH8102 to phosphate and zinc scarcity and cadmium additions Cox, Alysia D.; Saito, Mak A. (Frontiers Media, 2013-12-17)Synechococcus sp. WH 8102 is a motile marine cyanobacterium isolated originally from the Sargasso Sea. To test the response of this organism to cadmium (Cd), generally considered a toxin, cultures were grown in a matrix ...
Nutrients and pigments from HPLC analysis for fire ash deposition to coastal ocean study, southern California, December 2017 Valentine, David L. (Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: firstname.lastname@example.org, 2019-09-25)Nutrients and pigments from HPLC analysis for fire ash deposition to coastal ocean study, southern California, December 2017. For a complete list of measurements, refer to the full dataset description in the supplemental ...
Xue, Zichen; Rehkamper, Mark; Horner, Tristan J.; Abouchami, Wafa; Middag, Rob; van de Flierdt, Tina; Baar, Hein J. W. de (2013-09-09)Cadmium concentrations and isotope compositions were determined for 47 seawater samples from the high nutrient low chlorophyll (HNLC) zone of the Atlantic sector of the Southern Ocean. The samples include 13 surface ...