Phytoplankton functional groups and

Tagliabue A, Arrigo KR (2005) Iron in the Ross Sea, Part I impact on C02 fluxes via variation in phytoplankton functional group and non-Redfield stoichiometry. J Geophys Res 110(C03009). DOI 10.1029/ 2004JC002531... 

Tozzi, S., Schofield, O., and Palkowski, P. G. (2004). Historical climate change and ocean turbulence as selective agents for two key phytoplankton functional groups. Mar. Ecol. Prog. Ser. 274, 123-132. 

Iglesias-Rodriguez D. M., Brown C. W., Doney S. C., Kleypas J. A., Kolber D., Kolber Z., Hayes P. K., and Ealkowski G. P. (2002) Representing key phytoplankton functional groups in ocean carbon cycle models coccolithophorids. Global Biogeochem. Cycles 16 (in press). 

Tozzi S. (2001) Competition and succession of key marine phytoplankton functional groups in a variable environment. IMCS. New Brunswick, Rutgers University, 79. 

Tozzi S., Schofield O., and Falkowski P. (2003) Turbulence as a selective agent of two phytoplankton functional groups. Global Change Biology (in press). 

Fig. 1 Schematic representation of the processes and pools involved in the marine biogeochemical cycling of DMSP and DMS. Dominant role of functional groups in the different processes is indicated by coloured ellipses green, phytoplankton blue, zooplankton red, bacteria black, abiotic factors.

All eukaryotes and some prokaryotes such as cyanobacteria synthesize metal binding proteins— known collectively as metallothioneins—in response to high concentrations of several metals including Cd. These are cysteine-rich, low molecular mass polypetides whose thiol functional groups have high affinity for soft cations such as Cd " " [36], All plants, including phytoplankton, synthesize class... 

Over the last three decades, we have moved from the monoHthic view that nitrogen is the primary limiting nutrient for phytoplankton in the world s oceans (e.g., Thomas, 1966 Ryther and Dunstan, 1971), to the recognition that iron, silicon or phosphorus may at times be in shortest supply. Further, it is recognized that separate groups with distinct biogeochemical functions exist within the phytoplankton that may concur-rendy exhibit limitation by different nutrient factors (Dugdale and Wilkerson, 1998). 

Figure 10.8. Schematic model of metal ion uptake through a membrane of a phytoplankton cell, (a) The metal ion is bound to the outside surface of the cell either by biologically released ligands or by surface functional ligand groups subsequently to the surface complex formation. The metals are carried—usually by porter molecules—to the inside of the cell. If the transport into the cell is slow in comparison to the pre-equilibration process on the solution side, then the uptake of the metal ion of the cell depends on the free metal ion activity, (b) Solution variables outside and inside the cell.

The olefins are more labile than saturated compounds and therefore the chance of isolation of this group from sea water is low. The 21 6 hexa-olefin present in algae serves some special biochemical function and is a very labile compound even in the dark. It was first isolated from sea water by Blumer (1970) and subsequently detected by Schultz and Quinn (1977) in phytoplankton culture and sea-water samples. 

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