SOUTHERN OCAEN– Phytoplankton were active in these waters during this June cruise. Although ten times lower than in the summer, their rates show an active winter community, able to survive the winter and take advantage of increased light once the days lengthen in spring.
Carbon uptake, measured on board the ship in 24-hour incubations exposed to natural light, varied from 31 to 52 grams carbon per square meter of ocean surface per day.
To represent the lighted area of the ocean, we collected water at different depths from 0 to 100 meters and placed it under conditions of simulated light provided by various layers of screening.
The incubations are carried out under running seawater collected by the ship’s seawater intake.
This is a special incubator built to avoid freezing of the water lines during particularly cold periods.