Oligotrophic
Oligotrophic refers to any
environment which offers little to sustain
life. This term is usually used to describe bodies of
water or
soils with very low
nutrient levels.
Greek etymology:
Oligo : small, little, few; and
trophe: nutrients, food.
Oligotrophic environments are of special interest for the alternative
energy sources and survival strategies life could rely upon.
An especially fascinating example of such a lake is
Lake Vostok, a liquid freshwater lake which has been isolated from the world beneath 4 km of
Antarctic ice for approximately 500,000 years.
An example of oligotrophic soils are those on white-sands, with
soil pH lower than 5.0, on the
Rio Negro basin on northern
Amazonia that house very low-diversity, extremely fragile forests and savannahs drained by
blackwater rivers. These owe this colour to the high concentration of
tannins,
humic acids and other organic compounds derived from the very slow decomposition of plant matter.
In addition, an example of an oligotropic system is the Florida Everglades
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Oligotroph organism
