Environmental conditions and C and N uptakes of phytoplankton in the Bering and Chukchi seas, 2008

Based on high f-ratios in the central Arctic sea, nitrate uptake rates compared to ammonium uptake rates were relatively higher than those from other studies. The productivity of the algae in melting ponds ranged from 0.01 to 0.34 mg C m-3 h-1(average± S.D.= 0.09±0.11 mg C m-3 h-1) which were some what higher than those of phytoplankton(average± S.D.= 0.07±0.06 mg C m-3 h-1) at surface water over 80°N in the Arctic Ocean.

From the careful examination on micro algae communities within or under sea ice at the refrozen surface of the melting ponds, they are believed to an important food source for the zooplanktons such as copepods and amphipods as well as Arctic cods before along winter period. However, current and on going climate changes such as a sea ice decrease are expected to impact largely on this unique habitat in the melting ponds. 1) Primary production measurement by phytoplankton using a 13C-15N dual isotope tracer 2) Developmental stages of melting ponds and ice algal productivity