AN INSTRUMENT FOR SAMPLING WATER FROM THE BENTHIC BOUNDARY-LAYER

The BIOPROBE system, an instrumented tripod is described. It collects water samples and time-series data on physical and geological paramete rs within the benthic boundary layer in the deep sea at a maximum dept h of 4000 m. For biogeochemical studies, four water samples of 151 eac h can be collected between 5 and 60 cm above the sea-floor. BIOPROBE c ontains three thermistor flow meters, three temperature sensors, a tra nsmissiometer, a compass with current direction indicator and a bottom camera system. During R.V. Meteor Cruise 17 in July 1991, BIOPROBE wa s successfully used on the continental slope of the western Barents Se a at a depth of 1370 m. Analyses of dissolved and particulate matter i n layers of 10, 15, 25 and 40 cm above the seafloor showed strong vert ical gradients.