Picophytoplankton

Worden, A. Z., Nolan, J., and Palenik, B. (2004). Assessing the dynamics and ecology of marine picophytoplankton The importance of the eukaryotic component. Limnol. Oceanogr. 49, 168-179. 

Llabres, M., and Agusti, S. (2006). Picophytoplankton cell death induced by UV radiation Evidence for oceanic Atlantic communities. Limnol. Oceanogr. 51(1), 21—29. 

Unicellular cyanobacteria fix N2 in the subtropical North Pacific Ocean. Nature. 412, 635-638. Zehr, J. P., Jenkins, B. D., Short, S. M., and Steward, G. F. (2003). Nitrogenase gene diversity and microbial community structure a cross-system comparison. Environ. Microbiol. 5, 539—554. Zeidner, G., Preston, C. M., Delong, E. F., Massana, R., Post, A. F., Scanlan, D. J., and Beja, O. (2003). Molecular diversity among marine picophytoplankton as revealed by psM analyses. Environ. Microbiol. 5, 212—216. 

Argentinean Sea (4) 45°S 66°W January 1999 marine/eutrophic 19°C small 0.2-2 nm large >10 iim. small picophytoplankton, bacteria large diatoms... 

A.G.J. Buma, E.W. Helbling, M.K. de Boer, V.E. Villafane (2001). Patterns of DNA damage and photoinhibition in temperate South-Atlantic picophytoplankton exposed to solar ultraviolet radiation. J Photochem. Photobioi B Biol, 9-18. 

Reckermann, M. and Veldhuis, M.J.W. (1997) Trophic interactions between picophytoplankton and micro- and nanozooplankton in the western Arabian Sea during the NE monsoon 1993. Aquatic Microbial Ecology, 12, 263—273. 

Raven, J.A. (1998) The twelth Tansely lecture. Small is beautiful the picophytoplankton. Functional Ecology, 12, 503—513. 

For the LOHAFEX experiment, an area in the ocean had to be found where currents go in a circular pattern. This was necessary so that the iron would not be dispersed over a vast area too soon after deposition. The ideal site was close to Antarctica at the southern latitudes of 48° and western longitude of 16°. This was the center of a clockwise circirlar cirrrent of area of 10,000 km. During the experiment, chlorophyll concentration increased to double or triple of its pre-experiment value. This increase was detectable from space. Very small (0.2-2 pm sized) plankton called picophytoplankton were the driving engine of the growth, but they were promptly eaten by zooplankton. 

This late discovery was most probably a consequence of the size of the cells of Prochlorococcus. With an average diameter of 0.6 p.m (600 nm), Prochlorococcus are currently the smallest known photosynthetic prokaryotes the term picoplankton (or picophytoplankton ) was coined to describe them. In comparison, the average size of a prokaryote cell is S m, and that of a eukaryote cell is 50 pm, so in size Prochlorococcus are intermediate between viruses (20-300 nm) and other Eubacteria. In spite of their small size, these bacteria are capable of photosynthesis and, taking into account their abtmdance in the oceans, it is certain that they play a paramotmt role in the absorption of atmospheric carbon dioxide and thus contribute significantly to the thermal balance of the planet... 

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