Coccolithophores blooms

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... 

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. 

In 1997, combined effects of the AO and El Nino-Southern Oscillation (ENSO), resulted in relatively calm winds and reduced cloud cover over the Bering Sea. The increased sunlight caused the surface water temperature to rise more than 2°C above normal, hut few nutrients were present in the stratified water. These conditions favoured a coccolithophore bloom instead of diatoms which typically form the base of the summer food web. Since coccolithophores became established in the Bering Sea in 1997, they have been present in subsequent years even though weather conditions have returned to more normal states. 

Widdicombe, C.E., Archer, S.D., Burkill, P.H. and Widdicombe, S. (2002) Diversity and structure of the microplankton community during a coccolithophore bloom in the stratified northern North Sea. Deep-Sea Research II— Topical Studies in Oceanography, 49, 2887—2903. 

Many details are still obscure, and data are only available from a limited number of species, but it appears that most coccolithophores alternate between fully armored (heterococcolith-covered) diploid life stages and less-well-armoured (either holococcolith-covered or else naked) haploid phases. Both phases are capable of indefinite asexual reproduction, which is rather unusual among protists. That sexual reproduction also occurs fairly frequently is evidenced by the observation of significant genetic diversity within coccolithophore blooms. Bloom populations do not consist of just one clone... 

Tyrrell T, Holligan PM, and Mobley CD (1999) Optical impacts of oceanic coccolithophore blooms. Journal of Geophysical Research, Oceans 104 3223-3241. 

Davis, R.F., Stabeno, P.J., and Cullen, J.J. (2000). Use of optical measurements from moorings to detect coccolithophore blooms in the Bering Sea. In Proceedings of Ocean Optics XV Conference, Monaco. CD-ROM. 

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... 

In addition to our lack of knowledge about the exact benefit of a coccosphere, we also have rather little definite knowledge as to the ecological conditions that favor coccolithophore success. There is certainly variation between species, with some being adapted to relatively eutrophic conditions (although diatoms invariably dominate the main spring blooms in... 

Retaining river water within man-made reservoirs also can affect water quality. For example, reservoir retention of silicate-rich river water can lead to diatom blooms within the man-made lakes and thus depletion of silicate within the river water. One result is that increased ratios of dissolved nitrate and phosphate to dissolved silica may have helped change primary production in coastal areas from diatom-based to dinoflagellates and coccolithophor-ids. One result of this altered production may be increased hypoxia in coastal and shelf waters in the north-western Black Sea and other areas off large rivers. 

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