The Benthos of Arctic Seas and its Role for the Organic Carbon Cycle at the Seafloor

Abstract

The exploration of the Arctic Ocean has a long and multi-national history, but still we are only beginning to understand the role of the Arctic Ocean in the global carbon cycle. This chapter addresses the contribution of the Arctic benthos to organic carbon utilization, modification and sequestration. We review findings in benthic ecology and biogeochemistry of the Arctic Ocean from the past 15 years. Several older reviews on the Arctic benthos are available with a different focus: Zenkevitch’s (1963) thorough volume covering the entire Eurasian Arctic benthos remains outstanding in its description of species composition, biomass and biogeographic aspects. Reviews by Curtis (1975), Dayton (1990), and Carey (1991) cover general aspects of the Arctic benthos as well as distribution patterns, productivity, and the feeding ecology of different species. Many recent studies have emphasized processes at the sediment-water boundary layer including respiration of sedimentinhabiting communities or single species (Piepenburg et al. 1995), calculation of carbon utilization and remineralization rates of benthic communities and their correlation to primary production (Boetius and Damm 1998), but also measuring biomass of benthic populations (Seiler 1999; Jørgensen et al. 1999; Deubel 2000). Recent discoveries of cold seeps north of the polar circle (Vogt et al. 1999) and of hydrothermal activity on the Gakkel Ridge (Thiede 2002) suggest a more diverse deep-sea benthos than previously known, but these on-going investigations cannot be reviewed herein.