Primary production in the upper sea ice

Observations and expenments were conducted on fast ice in McMurdo Sound, Antarctica, to investigate seasonal changes in primary production in the upper sea ice intenor. In November and early December 1995, a dense phytoflagellate assemblage developed in the brine channels and pockets at a snow-free site. Primary production was calculated from I4C measurements of primary productivity in brine samples combined with estimates of the proportion of the ice volume occupied by brine.