Las bacterias extremófilas de los ríos ácidos de Huelva

Resum

Many rivers and streams in the Andévalo mining region are linked to the Iberian Pirytic Belt and to the miningexploitation that has been taking place in the area for more than 4,000 years. Their waters are characterized byan intense red color, by their extreme acidity and by transporting a variety of metals. Although it was thoughtthat such waters lacked life, a rich community of eukaryotic micro-organisms and bacteria have been identified.This is mainly composed of aerobic, hyperacidophilic aerobic bacteria, with Acidithiobacillus ferrooxidans beingthe most abundant species. These bacteria are responsible for a large part of the so-called Acid Rock Drainage(when the anthropogenic effect is not considered) or the Acid Mine Drainage –when its intensity depends on miningoperations–, a phenomenon that gives rise to these coloured, acidic and metals-transporting waters. On the otherhand, these bacteria have increased interest in the biometallurgical industry due to their oxidative capacity andleaching capacity of reduced inorganic compounds such as metal sulfides, since they can be applied to recovermetals from depleted mines, drainage waters, or materials derived from the industry, so they have a commercialinterest. In another sense, the elimination of metals from various wastes also has the growing interest in improvingenvironmental quality and favoring sustainable development.