The essential bioactive role of nickel in the oceans: Evidence from nickel isotopes ...

• Main Authors: Lemaitre, Nolwenn, Du, Jianghui, De Souza, Gregory, Archer, Corey, Vance, Derek
• Format: Text
• Language: English
• Published: ETH Zurich 2022
• Subjects: nickel isotopes; phytoplankton requirement; bio-availability; GEOTRACES; North Atlantic
• Online Access: https://dx.doi.org/10.3929/ethz-b-000541837; http://hdl.handle.net/20.500.11850/541837

The role of nickel (Ni) in ocean biogeochemical cycles is both under-studied and controversial. Strong correlations between Ni and organic carbon in modern and ancient marine sediments suggest a prominent biogeochemical role over a substantial portion of Earth history. Addition of Ni to culturing and seawater incubation experiments produces strong responses in terms of cell growth, particularly of nitrogen-fixing organisms. But the implied limiting role for phytoplankton growth is inconsistent with observations in the real ocean, specifically that photic zone Ni concentrations never descend to the very low values that characterise other bioactive, and often bio-limiting, metals like iron. These two observations can be reconciled if a large portion of the total dissolved Ni present in open-ocean surface waters is not bio-available on short timescales. Here we present new Ni concentration and stable isotope data from the GEOVIDE transect in the North Atlantic. We interpret these new data in the light of the ... : Earth and Planetary Science Letters, 584 ...