Sea-ice interface

Due to the ever changing structure of the ice at the sea/ice interface, space in between the ice crystals is no longer a limiting factor (Thomas 2004). Allowing the highest recorded biomass to occur it just the last few meters of the ice floe. The interface is a highly rich in DOM and nutrients due to the brine being expelled from the ice lattice. Large amounts of copepods congregate within the interface feed to on the water column. These species are hardly ever witnessed within the ice it’s self, mostly likely due to the large size of the organisms. But there has been research that shows that copepods as small a 1 mm still don’t venture into ice, showing that the extremes changes in salinity and temperature are that taken place within are a major for certain species problem. Other advantages the interface is used for is for a sanctuary for organisms, using the slow moving the boundary layer to take refuge from prey or the fast moving currents.

Krill (Eurhausia superb) are the most important species of the Southern Ocean, as they are the key species of its whole food web (Hansom et al.1998), removing them would cause an ecological disaster on a massive scale. Many marine species depend on krill for survival such as the Baleen whale, squid and penguins. Krill are in such abundance in the Southern Ocean that there biomass outweighs the mass of all humans on the Earth by 3 times (Thomas 2004). Krill feed on the sea- ice algae and bacteria that can be found on the underside of ice floes, and are vital for the krill to survive the winter months. It is known now that the link between the condition of the sea-ice and the distribution pattern of the krill, as the longer there is sea ice the high the krill recruitment will be (Thomas 2004).

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