A mesoscale phytoplankton bloom in the polar Southern Ocean stimulated by iron fertilization

@article{Boyd2000AMP,
  title={A mesoscale phytoplankton bloom in the polar Southern Ocean stimulated by iron fertilization},
  author={Philip W. Boyd and Andrew J. Watson and Cliff S. Law and Edward R. Abraham and Thomas W. Trull and Robin C. Murdoch and Dorothee C. E. Bakker and Andrew R. Bowie and Ken O. Buesseler and Hoe Chang and Matthew A. Charette and Peter L. Croot and Kent B. Downing and Russell D. Frew and Mark Gall and Mark G. Hadfield and Julie A. Hall and Mike J. Harvey and Greg Jameson and Julie LaRoche and Malcolm I. Liddicoat and R. D. Ling and Maria T. Maldonado and Robert Michael L McKay and Scott D. Nodder and Stuart Edward Pickmere and Richard D. Pridmore and Stephen Rich Rintoul and Karl Safi and Philip J. H. Sutton and Robert F. Strzepek and Kim Tanneberger and Suzanne M. Turner and Anya M. Waite and John R. Zeldis},
  journal={Nature},
  year={2000},
  volume={407},
  pages={695-702}
}
Changes in iron supply to oceanic plankton are thought to have a significant effect on concentrations of atmospheric carbon dioxide by altering rates of carbon sequestration, a theory known as the ‘iron hypothesis’. For this reason, it is important to understand the response of pelagic biota to increased iron supply. Here we report the results of a mesoscale iron fertilization experiment in the polar Southern Ocean, where the potential to sequester iron-elevated algal carbon is probably… 
Effect of natural iron fertilization on carbon sequestration in the Southern Ocean
TLDR
It is found that a large phytoplankton bloom over the Kerguelen plateau in the Southern Ocean was sustained by the supply of iron and major nutrients to surface waters from iron-rich deep water below, suggesting that changes in iron supply from below may have a more significant effect on atmospheric carbon dioxide concentrations than previously thought.
Effect of iron supply on Southern Ocean CO2 uptake and implications for glacial atmospheric CO2
TLDR
Data are reported from a whole-ecosystem test of the iron-limitation hypothesis in the Southern Ocean, which show that surface uptake of atmospheric CO 2 and uptake ratios of silica to carbon by phytoplankton were strongly influenced by nanomolar increases of iron concentration.
Ocean Iron Fertilization for Scientific Study and Carbon Sequestration
The trace element iron has been recently shown to play a critical role in nutrient utilization, phytoplankton growth and therefore the uptake of carbon dioxide from the surface waters of the global
Southern Ocean deep-water carbon export enhanced by natural iron fertilization
TLDR
Data from the CROZEX experiment in the Southern Ocean is reported to test the hypothesis that the observed north–south gradient in phytoplankton concentrations in the vicinity of the Crozet Islands is induced by natural iron fertilization that results in enhanced organic carbon flux to the deep ocean.
The decline and fate of an iron-induced subarctic phytoplankton bloom
TLDR
The depletion of silicic acid and the inefficient transfer of iron-increased POC below the permanent thermocline have major implications both for the biogeochemical interpretation of times of greater iron supply in the geological past, and also for proposed geo-engineering schemes to increase oceanic carbon sequestration.
Does iron fertilization lead to rapid carbon export in the Southern Ocean?
The Southern Ocean has the potential to influence climate due to its large inventory of excess macronutrients such as nitrate and phosphate. It has been hypothesized that if the supply of the
Ecological and biogeochemical response of Antarctic ecosystems on iron fertilization and implications on global carbon cycle
The European Iron Fertilization Experiment EIFEX studied the growth and decline of a phytoplankton bloom stimulated by fertilising 10 km2 in the core of a mesoscale (80 × 120 km) cyclonic eddy south
Different reactions of Southern Ocean phytoplankton size classes to iron fertilization
TLDR
The results suggest that the demise of the iron-induced phytoplankton bloom is caused by a shift in composition of taxonomic groups, rather than the other way around, as previously suggested.
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References

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TLDR
Data are reported from a whole-ecosystem test of the iron-limitation hypothesis in the Southern Ocean, which show that surface uptake of atmospheric CO 2 and uptake ratios of silica to carbon by phytoplankton were strongly influenced by nanomolar increases of iron concentration.
Importance of iron for plankton blooms and carbon dioxide drawdown in the Southern Ocean
THE iron hypothesis1–3—the suggestion that iron is a limiting nutrient for plankton productivity and consequent CO2 drawdown— has been tested by small-scale experiments in incubation bottles in the
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TLDR
In situ measurements of fluorescence during IronEx II show that the iron enrichment triggered biophysical alterations of the phytoplankton's photosynthetic apparatus, resulting in increased photosynthesis capacities throughout the experiment and, hence, the observed bloom.
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There is compelling evidence that phytoplankton growth is limited by iron availability in the subarctic Pacific, and equatorial Pacific and Southern oceans. A lack of iron prevents the complete
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Several explanations for the 200 to 280 ppm glacial/interglacial change in atmospheric CO2 concentrations deal with variations in southern ocean phytoplankton productivity and the related use or
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TLDR
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TLDR
It is argued that the ribbon-like bloom was produced from the fertilized patch through stirring, growth and diffusion, and an estimate of the stirring rate is derived, which may have prevented the onset of silicate limitation, and so allowed the bloom to continue for as long as there was sufficient iron.
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