Abstract
The aim of the work was quantitative determination of Fe(III)-reducing bacteria in natural ecosystems of the Antarctic, the Arctic, the Dead and the Black Sea, middle latitude (Ukraine, Abkhazia) and the equatorial zone (Ecuador). It was used the method of quantitative determination of microorganisms by McCready and the colorimetric method for determination of Fe(II) compounds . Results. The systemic study of the number of Fe(III)-reducing bacteria of both hemispheres in the ecosystems of six geographic regions was carried out for the first time. High number of Fe(III)-reducing bacteria in natural ecosystems was experimentally shown. The number of Fe(III)-reducing bacteria ranged from 1.1•102 to 2.8•107 cells/g of absolutely dry sample. Conclusions. The presented data showed that Fe(III)-reducing bacteria are an integral part of natural ecosystems and can significantly affect the biogeochemical cycles of iron and carbon compounds transformation.