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GLOSSARY
Pelagic. Within the water column.
Phytoplankton. Plants floating in the water column.
Phytodetritus. Organic aggregates in the water column
and on the deep-sea bed formed from phytoplankton
debris.
Picoplankton. Plankton with dimensions from 0.2 to
2.0 mm.
Potential temperature (q). The temperature of deep
water once the heating effect of high pressure is
removed.
Plankton. Organisms floating in the water column,
mainly bacteria.
Sled or Sledge. A piece of apparatus towed over the
seabed.
Stenobathic. Having a narrow depth range.
Stepper motor. A very controllable form of motor
working on a series of pulses.
Suprabenthos. Those animals living in the water
column immediately above the seabed.
Surficial. At the very surface of the sediment.
Sverdrup (Sv). A measure of water flow (10
6 m
3 s
−1 ).
Trawl. A net for catching fish and large invertebrates.
Turbidite. A graded sequence of sediment, both
horizontally and vertically, laid down by a turbidity
current.
Zooplankton. Animals floating in the water column.