Oceans cycles

Fitzgerald, W.F. (1989) Atmospheric and oceanic cycling of mercury. In Chemical Oceanography (ed. Duce, R.A.). Vol. 10. Academic Press, London. 

Figure 9.22. Oceanic cycles of organic carbon, nitrogen, and phosphorus. DOC = dissolved organic carbon POC = particulate organic carbon NPP = net primary production DN = dissolved nitrogen PN = particulate nitrogen DP = dissolved phosphorus, PP = particulate phosphorus. C and N fluxes are in units of 1012 moles C and N y1 P fluxes are in units of 1010 moles P y1.

Figure 9.23. Oceanic cycles of strontium and sulfur. Sr fluxes are in units of 109 moles y 1 S fluxes are in units of 1012 moles y1. The imbalance for S suggests storage of S042" in seawater.

Simo R, Pedros-Alio C (1999b) Short-term variability in the open ocean cycle of dimethylsulfide. Global Biogeochem Cycles 13 1173-1181... 

Ocean circulation and the global ocean cycles of nitrogen, oxygen... 

Marine Bioinorganic Chemistry The Role of Trace Metals in the Oceanic Cycles of Major Nutrients... 

Particles represent important agents of transport in global ocean cycles of many trace elements, of carbon, and of other substances. Once introduced into the oceans, many trace elements are removed from seawater by scavenging (sorption, com-plexation, and other forms of surface reactions) to particles (Goldberg, 1954 Turekian, 1977). Scavenging and burial in marine sediments represents the principal loss process influencing the biogeochemical cycle of many trace elements in the ocean (Li, 1981). 

The isotopic composition of silicon in diatom opal has been investigated as a proxy for the degree of silicate utilization by diatoms, based on the fact that diatoms fractionate the silicon isotopes ( °Si and Si) during uptake (De La Rocha et al., 1997, 1998). This application is analogous to the use of nitrogen isotopes to study nitrate utilization, but with important differences. On the one hand, the upper ocean cycle is arguably simpler for silica than bio-available nitrogen, which bodes well for the silicon isotope system. 

Figures 14 and 15 show the fluxes of CO2 between reservoirs in the models. Figure 14 addresses the high heat-flow (p = 0.7) model. In these, the largest fluxes in Hadean time are associated with the oceanic cycle of crustal...

Morel, F. M.M., A.J. Milligan and M.A. Saito (2003) Marine bioinorganic chemistry the role of trace metals in oceanic cycles of major nutrients. In The Oceans and Marine Chemistry (ed. H. Elderfield), vol. 6, Treatise on Geochemistry (ed. H. D. Holland and K. K. Turekian), pp. 113-43. Oxford Elsevier-Pergamon. 

Figure 9. An oceanic cycle for iodine indicating the major pathways for transport and reaction of iodine species.

Michalopoulos, P. and Aller, R.C., 1995. Rapid clay mineral formation in Amazon delta sediments Reverse weathering and oceanic cycles. Science, 270 614-617. 

Fig. 12.2 Simplified representation of the imports and exports pertaining to oceanic cycles.

The marine nitrogen cycle is part of the much larger and interconnected hydrosphere-lithosphere-atmosphere-biosphere nitrogen cycle of the Earth. Furthermore, the oceanic cycles of carbon, nitrogen, and phosphorus are inextricably linked together through the production and remineralization of organic matter, especially near surface ocean phytoplankton production. This coordinated web of major bioelements can be viewed as the nutrient super-cycle. ... 

The oxygen isotope signature of sea water varies as a function of the processing of water in the oceanic cycle. The two chemical parameters, salinity and oxygen isotope ratio, are distinctive for various water types. The oxygen-18 to oxygen-16 ratio is represented in comparison to a standard. The notation is (50 which is defined as follows ... 

Dimethylsulfoniopropionate (DMSP) is a metabolite produced in considerable quantities by algae and phytoplankton, and which is of importance in the trophic chains equally important, this sidfobetaine is at the origin of the formation of dimefhylsulfide (DMS). These two molecules intervene in a dominant way in the oceanic cycle of sulfur (Yodi, 2002) ... 

In summary, extensive research has been carried out on the lanthanide geochemistry of marine hydrothermal vent systems. Lanthanides are good indicators of water/rock reactions between hydrothermal fluids and basalt, and reactions between Fe oxide particles and seawater. While the lanthanides undergo an active geochemical cycle in and above venting fluids, this cycle is not quantitatively significant with respect to river water fluxes and oceanic cycles and inventory. 

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