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Time-series particle flux and seasonal sediment community oxygen consumption (SCOC) were measured in Port Foster (160 m water depth), Deception Island, Antarctica, beginning in March 1999 and continuing through November 2000. Sediment traps were moored at 50 and 20 m above bottom and collected sedimenting material for contiguous periods of 10 to 18.3 days. Fluxes of material increased in mid-winter of 1999 and 2000 but were more notable in 1999. Fluxes were higher in the deeper sediment trap and there was an inverse relationship between mass flux and % organic carbon and particulate total nitrogen. A piston-operated grab respirometer was deployed at 160 m depth for 35–60 h in November 1999, and in February, May/June, and November 2000, to measure SCOC and recover the sediment for organic carbon, nitrogen and pigment composition. SCOC, as an estimate of sediment community carbon demand, exceeded the organic carbon flux to the seafloor (supply), and alternative sources of organic carbon input to the benthos are discussed. Highest SCOC occurred in the austral summer during a particle-flux sampling hiatus in the summer of 2000. Fluxes were positively correlated with local wind speed measured at a terrestrial station positioned on a hill overlooking Port Foster. There was also a positive correlation between the particulate matter fluxes and the ratio of chlorophyll a to phaeopigments, an indicator of the “freshness” of material entering the sediment trap at 20 mab. [Copyright &y& Elsevier]

An autonomous weather station (Terrestrial station) was developed and deployed at Deception Island, Antarctica, an active volcanic island, to monitor the daily weather conditions as part of a long time-series marine ecosystem study of the sunken caldera, Port Foster. The principal components of the Terrestrial station were a time-lapse digital camera, ultrasonic wind sensor, controller, wind turbine generators, and batteries. The Terrestrial station was installed on a ridge at 200 m altitude overlooking Port Foster and the surrounding terrain from 9 March 1999 until 20 November 2000. Ice cover on Port Foster began in late July 2000 and was intermittently visible through early November. Daily averaged wind speeds ranged from 0.2 m s−1 in October to 47.4 m s−1 in June, with the prevailing direction from the southwest and less frequently from the northeast. Daily averaged air temperatures fluctuated from a low of −12.6°C in August 2000 to 2.7°C in March 1999. Weather conditions measured at Deception Island were generally consistent with those concurrently measured in the region of the South Shetland Islands. Ice cover in Port Foster was less pronounced in 1999 and 2000 than reported in previous years, suggesting regional warming. [Copyright &y& Elsevier]

Examines the ecology of under-ice fauna, including the logistic intractability of the environment and the distribution and behavior of the animals in Weddell Sea, Antarctica. Use of free-vehicle acoustic instruments to monitor the abundance, vertical distribution, and size distribution; Use of target strength to generate estimates of animal body lenght.

A description of the oceanographic instrumentation developed and deployed at Deception Island, Antarctica during the period 9 March 1999 to 20 November 2000 as part of the ERUPT program is presented. This instrumentation includes (1) an autonomous weather station (Terrestrial station) to record daily conditions and ice-cover, (2) an underwater time-lapse camera/sediment trap array to photograph the abundance and movements of bottom-dwelling animals and collect sinking particulate matter, (3) an acoustic array to monitor movements of macrozooplankton and nekton, (4) an autonomous, vertically profiling pump sampler to capture and preserve plankton and nekton from discrete depths, (5) thermistor arrays to record water temperature at various depths, (6) an acoustic Doppler profiler to record current velocities at discrete depths, and (7) a piston-operated grab respirometer to measure sediment community oxygen consumption and recover sediments. The Terrestrial station and thermistor arrays, current meter and grab respirometer were the most successful instruments deployed, producing large data sets. The acoustic array produced some data of limited value, while the camera tripod and pump sampler produced no useful data due to technical and operational problems. [Copyright &y& Elsevier]