Long-term monitoring of marine ecosystem at King Sejong station in King George Island, Antarctica

Abstract

Microalgal assemblages at surface along with water temperature, salinity, and macronutrients were monitored daily from January to December at a fixed coastal site in Marian Cove, King George Island from 1996 to 2008. The annual mean water temperature ranged from -0.48 to 0.49 °C, whereas the annual mean salinity was from 32.5 to 34.3. In general, the temperature of the surface water at the site was highest (1.18 ± 0.36 °C) during the summer period (December to February) and lowest (-1.53 ± 0.22 °C) during the winter period (July to September). The salinity had an opposite trend with lowest (32.8 ± 0.68) during the summer and highest (33.7 ± 1.15) during the winter. The total chlorophyll-a generally started increasing from late November and had a peak (0.87 ± 0.32 mg Chl-a m-3) at around January-February when the water temperature is warmest in a year. Within the phytoplankton communities, small phytoplankton < 20 &#61549

m contributed more than 60 % of biomass. However, there are not distinct large blooms of the phytoplankton biomass all around the year. Although there were some seasonal fluctuations, the concentrations of major nutrients were always high enough for the phytoplankton growth, indicating the nutrients are not a main controlling factor in their growth in the region.