The Role of Giant Petrels in the Southern Ocean Ecosystem

The role of algae for sequestration of atmospheric mercury in the ocean is largely unknown owing to a lack of marine sediment data. We used high-resolution cores from marine Antarctica to estimate Holocene global mercury accumulation in biogenic siliceous sediments (diatom ooze). Diatom ooze exhibits the highest mercury accumulation rates ever reported for the marine environment and provides a large sink of anthropogenic mercury, surpassing existing model estimates by as much as a factor of 7. Anthropogenic pollution of the Southern Ocean began ~150 years ago, and up to 20% of anthropogenic mercury emitted to the atmosphere may have been stored in diatom ooze. These findings reveal the crucial role of diatoms as a fast vector for mercury sequestration and diatom ooze as a large marine mercury sink.

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Genetic structure and demographic inference of the regular sea urchin Sterechinus neumayeri (Meissner, 1900) in the Southern Ocean: The role of the last glaciation

PLoS ONE ◽

10.1371/journal.pone.0197611 ◽

2018 ◽

Vol 13 (6) ◽

pp. e0197611 ◽

Cited By ~ 7

Author(s):

Angie Díaz ◽

Karin Gérard ◽

Claudio González-Wevar ◽

Claudia Maturana ◽

Jean-Pierre Féral ◽

...

Keyword(s):

Genetic Structure ◽

Southern Ocean ◽

Sea Urchin ◽

Sterechinus Neumayeri ◽

Last Glaciation ◽

Demographic Inference

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Seasonal modulation of phytoplankton biomass in the Southern Ocean

Nature Communications ◽

10.1038/s41467-020-19157-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Lionel A. Arteaga ◽

Emmanuel Boss ◽

Michael J. Behrenfeld ◽

Toby K. Westberry ◽

Jorge L. Sarmiento

Keyword(s):

Southern Ocean ◽

Phytoplankton Biomass ◽

Light Availability ◽

Key Factors ◽

Division Rate ◽

Very Large Array ◽

Dissolved Iron ◽

Environmental Properties ◽

Limiting Nutrient

Abstract Over the last ten years, satellite and geographically constrained in situ observations largely focused on the northern hemisphere have suggested that annual phytoplankton biomass cycles cannot be fully understood from environmental properties controlling phytoplankton division rates (e.g., nutrients and light), as they omit the role of ecological and environmental loss processes (e.g., grazing, viruses, sinking). Here, we use multi-year observations from a very large array of robotic drifting floats in the Southern Ocean to determine key factors governing phytoplankton biomass dynamics over the annual cycle. Our analysis reveals seasonal phytoplankton accumulation (‘blooming’) events occurring during periods of declining modeled division rates, an observation that highlights the importance of loss processes in dictating the evolution of the seasonal cycle in biomass. In the open Southern Ocean, the spring bloom magnitude is found to be greatest in areas with high dissolved iron concentrations, consistent with iron being a well-established primary limiting nutrient in this region. Under ice observations show that biomass starts increasing in early winter, well before sea ice begins to retreat. The average theoretical sensitivity of the Southern Ocean to potential changes in seasonal nutrient and light availability suggests that a 10% change in phytoplankton division rate may be associated with a 50% reduction in mean bloom magnitude and annual primary productivity, assuming simple changes in the seasonal magnitude of phytoplankton division rates. Overall, our results highlight the importance of quantifying and accounting for both division and loss processes when modeling future changes in phytoplankton biomass cycles.

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The Role of Mixotrophy in Southern Ocean Ecosystems

Environmental Modeling & Assessment ◽

10.1007/s10666-019-09670-0 ◽

2019 ◽

Vol 24 (4) ◽

pp. 421-435 ◽

Cited By ~ 1

Author(s):

John Norbury ◽

Irene M. Moroz ◽

Roger Cropp

Keyword(s):

Southern Ocean ◽

Ocean Ecosystems

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Southern Ocean cephalopods: life cycles and populations (Proceedings of the symposium held at Kings College Cambridge, 5–9 July 1993)

Antarctic Science ◽

10.1017/s0954102094000192 ◽

1994 ◽

Vol 6 (2) ◽

pp. 136-136 ◽

Cited By ~ 1

Author(s):

P.G Rodhouse ◽

U. Piatkowski ◽

C.C. Lu

Keyword(s):

Southern Ocean ◽

Deep Sea ◽

Population Biology ◽

Marine Biology ◽

Life Cycles ◽

Systematic Sampling ◽

Ecological Studies ◽

Antarctic Marine ◽

Distribution Studies

The first systematic sampling in the Southern Ocean to capture cephalopods took place 120 years ago aboard HMS Challenger. Over the next century taxonomic knowledge was advanced by expeditions including the Mission du Cap Horn (France), the Valdivia Deep Sea Expedition (Germany), the Discovery expeditions (UK) the Eltanin (USA) and Academic Knipovitch (USSR). Over the last decade Southern Ocean cephalopod research has at last progressed beyond the descriptive phase and is rapidly joining other fields of Antarctic marine biology in its concerns with population biology and trophic systems, Although much taxonomic work remains to be done, ecological studies on the role of cephalopods in the diet of predators has been facilitated by advances in the identification of cephalopod beaks, development of opening-closing nets has allowed fine-scale distribution studies, and as methods for the study of growth, diet and biochemical genetics have advanced, so these have been applied to Southern Ocean cephalopods.

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