Coccolithophores

Zondervan, I. 2007. The effects of light, macronutrients, trace metals and C02 on the production of calcium carbonate and organic carbon in coccolithophores—A review. Deep-Sea Research II, 54, 521-537. 

Among the organs of living things consisting of calcite, the spicules of sea urchins and the exo-skeleton of coccolithophores attract particular interest. A sea... 

Coccolith, an exo-skeleton of coccolithophores, consists of calcite crystals of uniform size showing a most unusual morphology, which resembles a trug. The structure of the exo-skeleton consists of about thirty calcite crystals of equal size, which are regularly aligned and conjugated. This unusual form of calcite crystals (shown in Fig. 14.5) has stimulated particular interest, and many studies have been conducted on this structure [8]. 

Figure 14.5. Crystal orientation and mechanism of formation of calcite constituting the segment of coccolithophores. Emiliania huxleyi is presented as an example [8].

Until recently, no comprehensive survey of DMS production by phytoplankton has been made. Single clones of various marine species have been examined and of these, the coccolithophore, Hymenomonas (ex. Cricosphaera, Syracosphaera) carterae had the highest DMS levels (10.111. 

In the present ocean calcium carbonate formation is dominated by pelagic plants (coccolithophores) and animals (foraminifera, pteropods, and heteropods). Examples are presented in Figure 4.13. Although benthic organisms are important in shoal water sediments, and for dating and geochemical studies in the deep sea sediments, they constitute only a minor portion of the calcium carbonate removed from deep seawater. Shoal water carbonates are discussed in detail in Chapter 5. 

Meldrum, 2002), the elaborately shaped spicules in ascidians, and finely the sculpted coccolith shells in coccolithophores (Mann, 2001). For silica structure, the diatoms produce the most exquisite siliceous cell wall (Sumper and Brunner, 2006). Also the calcium phosphate in bone shows a highly regulated organization and arrangement. Interestingly, avians have two main biomineralization systems, one produces calcium carbonate for egg shell and the other produces calcium phosphate for bone (Bauerlein, 2000 Mann, 2001). 

Fig. 4 Calculation of a molecular clock, (a) The ml tree shown in Edvardsen et al. (2000) has been linearized (Kooistra and Medlin 1996) so that all rates of evolution are the same. Fossil dates from coccolithophore taxa are placed on nodes where these taxa have their first appearance in the fossil record (open circles on tree), (b) A regression of branch lengths against fossil dates has been performed...

Billard C, Inouye I (2004) What is new in coccolithophore biology In Thierstein FI, Young J (Eds). Coccohtho-phores - from molecular processes to global impact. Springer-Verlag, Berlin Fleidelberg, pp 1-30... 

Turner et al. 1988. Samples with >20% coccolithophores winter and summer 1985... 

Malin et al. 1993. June-July 1987. Samples with >50% of total carbon biomass as coccolithophores... 

Archer SD, Widdicombe CE, Tarran GA, Rees AP, Burkill PH (2001b) Production and turnover of particulate dimethylsulphoniopropionate during a coccolithophore bloom in the northern North Sea. Aquat Microb Ecol 24 225-241... 

Malin G, Turner S, Liss P, Holligan P, Harbour D (1993) Dimethylsulfide and Dimethylsulphoniopropionate in the Northeast Atlantic During the Summer Coccolithophore Bloom. Deep-Sea Res Part I 40 1487-1508 Malin G, Wilson WH, Bratbak G, Liss PS, Mann NH (1998) Elevated production of dimethylsulfide resulting from viral infection of cultures of Phaeocystis pouchetii. Lim-nol Oceanogr 43 1389-1393... 

Scale Coccolithophore Bloom In The Gulf Of Maine. Cont Shelf Res 13 831-843... 

Wilson WH, Tarran G, Zubkov MV (2002) Virus dynamics in a coccolithophore-dominated bloom in the North Sea. Deep-Sea Res Part II 49 2951-2963... 

Figure 2. Examples of typical calcium carbonate tests which are deposited in pelagic sediments. (1) and (2) are foraminifera (calcite) (3) is a coccolithophore (calcite) (4) and (5) are pteropods (aragonite). Note the difference in size as...

Boyd, P., Pomroy, A. J., Bury, S. J., Savidge, G., and Joint, I. (1997). Micro-algal carbon and nitrogen uptake in post coccolithophore bloom conditions in the NE Atlantic, July 1991. Deep Sea Res. 144, 1497-1517. 

Dyhrman, S. T., Haley, S. T., Birkeland, S. R., Wurch, L. L., Cipriano, M. J., and McArthur, A. G. (2006). Long serial analysis of gene expression for gene discovery and transcriptome profiling in the widespread marine coccolithophore EmUiania huxleyi. Appl. Environ. Microbiol. 11, 252—260. 

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