Impact of climate change on the Arctic benthos in the southeastern Beaufort Sea
Ship: CCGS Amundsen CA
Principal Investigator: Archambault, Philippe
Start Date: 28-03-2008
End Date: 02-08-2008
Citation: Link H, Archambault P, Tamelander T, Renaud Pe, Piepenburg D (2011) Spring-to-summer changes and regional variability of benthic processes in the western Canadian Arctic. Polar Biology 34:2025-2038
Abstract: Samples were collected at 5 sites ranging in water depth from 100 to 595 m at least once in each season (ice-covered and open-water condition) between March and August 2008 onboard the icebreaker CCGS Amundsen. At each sampling station, an USNEL box corer was deployed for collecting seafloor sediments. From each box core, 5 sub-cores of 11 cm diameter and 20 cm sediment depth were taken for assessing benthic carbon remineralisation in microcosm incubations and 3 additional subcores of 5 cm diameter and 10 cm length were taken for determining sediment properties. Incubations of sediment microcosms were run in a dark, temperature-controlled room (2-4 °C) for 24-48 h. Each sediment microcosm was sieved through a 0.5 mm mesh under running sea water at the end of incubations to determine biomass of macrofaunal communities. The sieve residue was preserved in a buffered 4% seawater-formaldehyde solution and analysed for species composition and abundance under a stereomicroscope in the lab. The objective was to describe how seasonal changes in the availability of food influence benthic carbon remineralisation - the rate of carbon cycling - in the southeastern Beaufort Sea. Our hypotheses were that (1) the availability of food for benthic communities increases significantly following the ice melt, (2) benthic biomass increases after the ice melt, (3) benthic carbon remineralisation increases significantly following ice melt, and (4) spatial variability of benthic carbon remineralisation is determined by both food availability and benthic community patterns, here tested as biomass.