Phytoplankton

Diatoms use a stolen bacterial gene to commit iron piracy

Joint Science Highlight with US-Ocean Carbon & Biogeochemistry (US-OCB). Much of the primary production in low-iron marine environments is carried out by diatoms, and therefore the details of how these phytoplankton acquire the iron they need can have major impacts of biogeochemical cycles. The proteins involved in this process are largely unknown, but in 2018 […]

Jan / 23 / 2020

Drawing the future of phytoplankton in a changing ocean

Phytoplankton development is strongly linked to the dissolved iron availability in the surface waters. Iron’s behavior is sensitive to warming, stratification, acidification and de-oxygenation. In a changing ocean, these processes in addition to nutrient co-limitation interactions with iron biogeochemistry will all strongly influence phytoplankton dynamics. This paper establishes the potential future shifts in multiple facets […]

Mar / 14 / 2017

Metal contents of North Atlantic phytoplankton across environmental gradients

Twining and co-workers (2015, see reference below) provide the first direct measurements of metal quotas in phytoplankton from across the North Atlantic Ocean (US GEOTRACES GA03), known to be subjected to aeolian Saharan inputs and anthropogenic inputs from North America and Europe. The authors combine chemical leaches (to extract biogenic and otherwise labile partiulate phases) […]

Nov / 25 / 2015

When direct mapping of diatoms reveals unexpected fate of trace metals in the twilight zone

Twining and co-authors (2014, see reference below) used synchrotron x-ray fluorescence mapping to measure macronutrients such phosphorus (P), sulphur (S), and silicon (Si), and also trace metals like iron (Fe), nickel (Ni) and zinc (Zn), in individual cells of a diatom specie during a spring bloom off New Zealand. They clearly show that P, S, […]

Jan / 20 / 2015

Arsenic detoxification by phytoplankton reveals that arsenic species could be good proxies of phosphorus limitation

Some phytoplankton species have the capacity to modify surface water arsenic speciation, inhibiting its toxicity. Such detoxification is operative in oligotrophic waters when phosphate concentrations are below those for arsenic (As). During the US GEOTRACES North Atlantic transect, fine determination of As speciation allowed establishing the potential use of these detoxification products as indicators of […]

Mar / 26 / 2013

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