Particle Fluxes at the Edge of the Ross Ice Shelf: the Rôle of Physical Forcing
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2.1 Mooring Array
The mooring line carried two sédiment traps of identical design (Hydro-Bios
Multi Sédiment Trap MST 24), equipped with 24 receiving cups, with programmed collection intervals of 15 days. Traps were characterized by a collection area of 0.6 m2 and fitted with a 5-cm-thick square plastic baffle (3.5-cm cell
diameter) mounted to the opening. In order to hinder dégradation of settled
material and avoid breaking of “swimmers” the receiving cups were filled
before deployment with a solution of buffered 5% formaldéhyde in 0.45 m prefiltered seawater. The two traps were placed at 230- and 423-m depth in a 602m water column, but unfortunately the upper trap did not work, owing to the
failure of the stepping motor, and for this reason time sériés samples are not
available at this depth. Particle presence was, however, recorded by a transmissometer fixed to the framework of the 230-m trap, which measured the atténuation of a red monochromatic light beam over a pathlength of 0.25 m, with
records resulting from the average of eight measurements performed every 30