Ecological significance in different characteristics of bottom sea ice algae at different regions of the Arctic Ocean

Abstract

The different characteristics of inorganic nutrients in the water column and sea ice, chlorophyll-a concentrations, and carbon and nitrogen uptake rates of ice algae and phytoplankton were compared between the land fast-sea ice at Barrow as a coastal condition and the first-year sea ice at the ICEX site as a oceanic condition during the similar period (early April) in 2003. The results showed three ecological implications for bottom ice algae in the Arctic Ocean: 1) Different nutrient reservoirs within sea ice and in the surface water column below the sea ice at different locations might control maximum biomass of bottom ice algae and thus the relative contribution of ice algae production, 2) different initial biomass of bottom ice algae might change the timing of bloom, 3) the fate of the ice algae at the bottom of sea ice might be different among the various geographic areas depending on their size composition, especially between coastal and oceanic environments. The specific characteristics of bottom sea ice algae at different locations, especially for coastal and oceanic environments, should be carefully considered in the future ice-ocean biogeochemical modeling in the Arctic Ocean.