Biogeochemical cycles and ecological processes

Superimpose the attributes of the Arctic environment upon the cycles of these biological precursors, and what arises is a system of biological production, transformation and losses unique in the global ocean system. Continental shelves are a key feature that influence greatly the production and cycling of organic matter in the Arctic Ocean. Water masses exiting different Arctic shelves 

Terrestrial and marine biomarkers have aided in understanding how Arctic shelf systems process, metabolize and sequester carbon (Opsahl etal., 1999). Biomarkers have been used to trace the dispersal of DOC and POC on the Canadian Beaufort shelf, leading to a better understanding of the importance of terrestrial sources to the carbon budget of major riverine-influenced systems (Yunker etal., 1995 Macdonald etal., 1998). 

Ice is a key attribute linked to cycles of primary productivity on continental shelves. Marginal ice zones (MIZ) are some of the most dynamic areas in the world s oceans with large seasonal and inter-annual fluctuations in ice cover and ice transport. These are unique habitats with specific communities dependent upon the physicochemical structure of the ice (Thomas Dieckmann, 2002). 

Pelagic arctic animals have adapted to strong seasonality by storing large amounts of lipids as energy reserves. The proportion of lipid to dry body mass 

Direct physical disturbance events can also play a strong role in shaping benthic communities on local scales. Major disturbance from iceberg scour in the Arctic and Antarctic caused shifts in community structure from one of high diversity to one dominated by pioneer species, with effects lasting up to a decade (Gutt etal., 1996). Both direct disturbance and indirect effects (e.g. local temperature and salinity anomalies) have the potential to play a central role in shaping benthic community composition at smaller scales. 

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