Vertical flux of particles in the ocean

Sedimentation of organic and inorganic particulate material in Lindaspollene, a stratified, land-locked fjord in western Norway

“…If the particle diameter of suspended POM decreases severely in the lower part of the upper water column in Lindbspollene, i.e. due to the effect of grazing herbivores, coprophagy, resuspension of fecal material after the dissolution of the pellicula etc., the sedimentation rate would decrease markedly since the sinking rate of a particle decreases exponentially with decreasing diameter (McCave, 1975). Such a delay in sedimentation would lead to higher pelagical mineralization rates in the water column and, therefore, result in a lower amount of sedimenting material and lower numbers of recognizable particles.…”

A steady state model of particulate organic carbon flux below the mixed layer and application to the Joint Global Ocean Flux Study

“…While it is well documented that coagulation of particulates into large aggregates facilitates the export of POC from the mixed layer by sinking [McCave, 1975], the influence of physical processes like coagulation and fragmentation on the flux of biogenic carbon below the mixed layer has yet to be elucidated. Our results suggest that coagulation and fragmentation do not affect the mass flux of biogenic carbon below the mixed layer, provided that the clearance rate function ½i and the sedimentation velocity w i have approximately the same dependence on aggregate size (i.e., e • 0).…”

“…The downward flux of particulate organic carbon (POC) from the mixed layer strongly depends on the rate at which particulate matter is packaged into fast sinking aggregates by coagulation [McCave, 1975]. When coagulation rates are fast, the resulting flux of aggregates through the water column has been likened to the world's greatest snow storm [Alldredge and Silver, 1988].…”

The chemical composition of macroscopic aggregates in two neretic seas1

“…Some workers have suggested that much of the flux of material downward in the ocean occurs through the sinking of large, relatively rare particles (McCave 1975;Bishop et al 1977). My findings that an average 25% of total POC and PON in the Santa Barbara Channel is concentrated on particles 3 mm or larger lends strong support to these conclusions, if macroscopic aggregates have relatively high settling velocities.…”

“…Suspended sediment traps collect many apparently large, heavy, and dense particles (Bishop et al 1977). McCave (1975) suggested that most material reaching the benthos does so rapidly as aggregates.…”