Primary production in the Southern Ocean, 1997–2006

Phytoplankton chlorophyll distributions and primary production in the Southern Ocean

Satellite ocean color data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) were used to examine distributions of chlorophyll concentration within the Southern Ocean for the period October 1997 through September 1998. Over most of the Southern Ocean, mean chlorophyll concentrations remained quite low (,0.3–0.4 mg m). Phytoplankton blooms where chlorophyll concentration exceeded 1.0 mg m...

Tight coupling of primary production and marine mammal reproduction in the Southern Ocean.

Polynyas are areas of open water surrounded by sea ice and are important sources of primary production in high-latitude marine ecosystems. The magnitude of annual primary production in polynyas is controlled by the amount of exposure to solar radiation and sensitivity to changes in sea-ice extent. The degree of coupling between primary production and production by upper trophic-level consumers ...

Satellite derived euphotic depth in the Southern Ocean: Implications for primary production modelling

Threshold of gross primary production for planktonic metabolic balance in the Southern Ocean: An experimental test

The proposed threshold planktonic gross primary production (GPP) value for O2 of 2.05 mmol m23 d21 separating net heterotrophic from net autotrophic communities in the Southern Ocean was tested experimentally using large mesocosms (20 m3). A set of eight mesocosms was moored in Johnson’s Dock (62839.5769S, 60822.4089W, Livingston Island, Antarctica) and a gradient of GPP was experimentally gene...

Factors limiting heterotrophic bacterial production in the southern Pacific Ocean

The role of potential factors limiting bacterial growth was investigated along vertical and longitudinal gradients across the South Eastern Pacific Gyre. The effects of glucose, nitrate, ammonium and phosphate additions on heterotrophic bacterial production (using leucine technique) were studied in parallel in unfiltered seawater samples incubated under natural daily irradiance. The enrichments...