HORIZONTAL VARIATION OF THE PARTICLES FLU X AT MICROSCALE AND MESOSCALE ON THE CALIFORNIA ABYSSAL-PLAIN (4100-M DEPTH)

Nine sediment traps were assembled in triplicate on a frame and deploy ed at 100 m above the bottom in the California abyssal plain (4 100 m depth) for ten days. The distances between traps were from 30 cm to 11 km. The main flux measured during this period was 167 mg m(-2) day(-1 ) with a minimum of 43 mg m(-2) d(-1) and a maximum of 283 mg m(-2) d( -1). This high variation of the particulate flux at the kilometric sca le was also observed at a metric scale: for example, the particulate f lux measured with one of triplicate traps was equal to 82.3 +/- 46.5 m g m(-2) d(-1) (more than 50 % of variation) between traps distant of l ess than 1 m. To explain this heterogeneity of the flux measurement, s ome hypotheses are developed in this study: sampling artefact, differe nt hydrological conditions, heterogeneous production, or distribution of particles in the water column.