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 parameters within the benthic boundary layer in the deep sea at a maximum depth of 4000 m. For biogeochemical studies, four water samples of 151 each can be collected between 5 and 60 cm above the sea-floor. BIOPROBE contains three thermistor flow meters, three temperature sensors, a transmissiometer, a compass with current direction indicator and a bottom camera system. During R.V. Meteor Cruise 17 in July 1991, BIOPROBE was successfully used on the continental slope of the western Barents Sea at a depth of 1370 m. Analyses of dissolved and particulate matter in layers of 10, 15, 25 and 40 cm above the seafloor showed strong vertical gradients.