Sediment flux deep oceans

Carbon in Intermediate and Deep Ocean Carbon in Ocean Sediments Marine Particulate Carbon Flux... 

Thunell R.C. and Honjo S. (1981) Planktonic foraminiferal flux to the deep oceanic sediment trap results from the tropical Atlantic and the central Pacific. Mar. Geol. 40, 237-253. 

Smith, K.L., Jr. (1987) Food energy supply and demand a discrepancy between particulate organic flux and sediment community oxygen consumption in the deep ocean. Limnol. Oceanogr. 32, 21-220. 

Upon settling to the surface sediments, trace metals can be recycled back into the dissolved phase and act as a source to the deep ocean. Pore-water concentrations of trace metals can be significantly higher than that observed in the overlying water column. Elevated pore-water concentrations suggested a potential for benthic fluxes of dissolved metals out of the sediment, which has been verified by direct measurements (Elderfield et al., 1981 Westerlund et al., 1986). 

As one approaches continents from the deep ocean, overlying productivity becomes greater and the water depth shoals so that particles are degraded less while sinking. Both factors increase the particulate organic matter flux to the sediment-water interface. This creates more extensive anoxia in the sediments, which is sometimes compounded on continental slopes by low bottom-water oxygen conditions. A natural... 

Hydrothermal and mantle contributions of methane are not significant. Oceanic surface waters are oversaturated with respect to methane, due to bacterial (methanogenic) activity in localized anaerobic environments, such as the digestive tracts of zooplankton, resulting in a net flux of methane to the air. Methane is similarly produced in freshwater environments. Deep ocean waters contain much lower methane concentrations than surface waters and the methane generated within anaerobic sediments is mostly oxidized by methanotrophes. Marine and lacustrine environments as a whole do not make a large contribution to the methane flux, but natural wetlands do. The bacterial... 

The source of Ra-226 in the deep ocean is the flux of Ra-226 from the ocean floor sediments where it forms by the decay of ionium (Th-230) (5, 41) and the decomposition of organic matter sinking through the water column (42, 43). The present concentration of Ra-226 at inter-... 

Fig. 6.13 Effect of seasonal changes in physical characteristics of surface water, as measured by instruments on a surface air-sea interaction buoy, on particle flux to the deep ocean, recorded by sediment traps at 2 229 m during 1994-95. These moorings were deployed close to the US JGOFS Sta. S7 (Fig. 6.4, inset). Redrawn from Honjo etal. (1999) with the data for the mixed layer depth (MLD, taken as the depth at which temperature decreased by 1°Q from Dickey etal. (1998).

---