The Vertical Flux of Particulate Organic Matter in the Peru Coastal Upwelling as Measured with a Free-Drifting Sediment Trap

摘要

An intercomparison of moored and free-drifting sediment traps of identical design was conducted off the coast of Peru in 1978. In each of three deployments to 30 m in a 120 m water column, the free-drifting sediment traps collected a greater amount of material. The quality of material in each type of trap also differed, material collected in the moored traps being of a consistently higher C/N ratio. Free-drifting sediment traps were used during 1977 and 1978 in an investigation of the vertical flux of particulate organic matter in the Peru coastal upwelling. Work was concentrated near the upwelling center located near 15 degrees S. The vertical flux of particulate organic carbon averaged about 9% of the daily primary production of carbon in Austral summer, 1977. In fall 1978 traps deployed at the base of the euphotic zone and at 50 m collected 20% and 10% of the daily primary production. Nocturnal fluxes were 50% greater than daytime fluxes. Qualitatively, night samples were distinguished from day samples by the presence of Euphausia mucronata molts. It is concluded that the vertical flux of particulate matter is an important component of the organic matter cycle of the Peru coastal upwelling ecosystem.