Global oceanic productivity

Crossland, C. J., Hatcher, B. G., and Smith, S. V. (1991). Role of coral reefs in global ocean production. Coral Reefs 10, 55-64. 

Chavez, F. P. and Toggweiler, J. R. (1995). Physical estimates of global new production The upwelling contribution. In "Upwelling in the Ocean Modem Processes and Ancient Records" (C. P. Summer-hayes, K.-C. Emeis, M. V. Angel, R. L. Smith and B. Zeitzschel, eds), pp. 313-320. John Wiley. 

Abstract Seawater concentrations of the climatecooling, volatile sulphur compound dimethylsulphide (DMS) are the result of numerous production and consumption processes within the marine ecosystem. Due to this complex nature, it is difficult to predict temporal and geographical distribution patterns of DMS concentrations and the inclusion of DMS into global ocean climate models has only been attempted recently. Comparisons between individual model predictions, and ground-truthing exercises revealed that information on the functional... 

Another aspect of the contribution of different species to global DMSP production is related to their ability to form blooms. Although Table 1 shows that the haptophytes do not have unusually high concentrations of DMSP per cell, the ability of Phaeocystis sp. and Emiliania huxleyi to dominate phytoplankton biomass during the formation of extensive coastal and oceanic blooms can result in elevated levels of DMS(P) (Table 2). These species therefore have received a great deal of research attention. Phaeocystis particularly is known to form almost mono-specific spring blooms. Within such blooms, DMSP production is constrained by abiotic factors that affect cell physiology and the ability to produce and retain DMS(P). This topic is explored in the next section. 

Galloway et al. (2004) recently estimated global oceanic N2 fixation to be in the range of 100-200 x 10 g year , roughly equal to the estimate for terrestrial N2 fixation in the absence of human activities. It now appears that upwards of 50% of the nitrogen supporting new production of some tropical and sub-tropical marine upper water column ecosystems could be derived from N2 fixation (Capone et al., 2005 Karl et al., 1997 MahafFey et al., 2005) (see Below). 

Longhurst, A., Sathyendranath, S., Platt, T., and CaverhiU, C. (1995). An estimate of global primary production in the ocean from satelhte radiometer data.J. Plank. Res. 17, 1245—1271. 

As an alternative to partial assimilatory NOs reduction by phytoplankton, oxidation of NH4+ by Bacteria and Archaea (the first step in the 2-step process of nitrification) can produce N02 as an intermediate product. Nitrifying bacteria were first isolated from the marine environment by Watson (1965) and are now known to be ubiquitous in the global ocean. Wada and Hattori (1971) used a sensitive chemical assay to measure changes in N02 in incubated samples, to conclude that NH4+ was the major source of N02 in the PNM in the central North Pacific Ocean. Miyazaki et al. (1973, 1975), using a N tracer method, found that, in Sagami Bay and in the western North Pacific, NH4+ and NOs were both important sources ofN02. ... 

The NO3 content of upweUing water is strongly influenced by the location of a system (Codispoti et al., 1982) in the global oceanic conveyer belt that transports deep water through the ocean basins (Broecker and Peng, 1982, their Fig. 1.12). From the North Atlantic to the Pacific and Indian Oceans through the Antarctic Circumpolar Current, there are increasing nutrients, from the faUout of surface productivity. 

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