All about (my) diatoms

Diatoms do not only have a use in water quality management, but other economical uses as well. These organisms are sought for their nutritional value. Silicon is an important micronutrient and diatoms have been steadily marketed for this reason. Other products are derived from diatomaceous earth (Fig. 1). This marine sediment is used as pest repellent or within filters, and has even been used in toothpaste. It also produces improved solar energy cell efficiency, which is readily publicized (Thomas 2014). More uses are known, including as a stabiliser for TNT, fertilizer and pesticide. Other economic effects of diatoms are less positive. They are early and active participants in the process of biofouling (Wahl 1989).
 
By Doc. RNDr. Josef Reischig, CSc. (Author's archive) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons​​
 Fig. 1 Diatomaceous earth (By Doc. RNDr. Josef Reischig, CSc. (Author's archive) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons)]

Finally, as already remarked, the ecological effect is important. Diatoms are a predominant primary producer. They are believed to produce from 20 to 40 % of the atmospheric oxygen (Field et al. 1998; Falkowski et al. 1993; Riding 1992). They also have important inputs into the carbon and silicon cycles, mostly due to their abundance (Falkowski et al. 1998).

Diatom fame: diatoms have also been in the cinema. The impressive (though aging) film from Alfred Hitchcock: "The Birds" was partially based on an occurrence of the domoic neurotoxin bearing Pseudonitzschia H. Peragallo that led birds to fall from the sky in Monterey Bay, California USA in 1961.

 
 
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References

Bargu, S., M. W. Silver, M. D. Ohman, C. R. Benitez-Nelson, & D. L. Garrison. 2012. "Mystery behind Hitchcock's birds." Nature Geoscience, 5(1), 2.
Falkowski, P. G., R. T. Barber, and V. Smetacek. 1998. “Biogeochemical Controls and Feedbacks on Ocean Primary Production.” Science 281: 200–206.
Falkowski, P. G., R. Greene, and Z. Kolber. 1993. “Light Utilization and Photoinhibition of Photosynthesis in Marine Phytoplankton.” In BNL. Brookhaven National Lab.
Field, C. B., M.J. Behrenfeld, J.T. Randerson, and P. Falkowski. 1998. “Primary Production of the Biosphere: Integrating Terrestrial and Oceanic Components.” Science 281 (5374): 237–40.
Riding, R. 1992. “The Algal Breath of Life.” Nature 359 (6390): 13–14.
Thomas, A. [Rehemat24]. 2014. “What Else Can Diatoms Be Used For?” 2014. http://diatoms.myspecies.info/node/203.
Wahl, M. 1989. “Marine Epibiosis. I. Fouling and Antifouling: Some Basic Aspects.” Marine Ecology Progress Series 58: 175–89.

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