Effects of Oxidation-Reduction Potentials on Soil Microbes

Abstract

Soil microbes are important in various processes that lead to soil fertility, nutrient availability and plant nutrition. These soil microbial organisms are themselves affected by the environment where they occur. Microbes could either be aerobic or anaerobic depending on their oxygen requirements. Oxidation-reduction reaction is a common reaction in anoxicenvironments and microbes tend to respond to it in different ways. This study therefore sets out to investigate the effect of oxidation-reduction potentials of the soil on activities of soil microorganisms. Results from this study show that highly reduced soils favors bacteria population more than fungi. It was concluded that the survival of fungi is best supportedunder oxidized and moderately reduced soils, but their existence can be negatively affected when soils become highly reduced. Bacteria that are aerobic thrive best under oxidized and moderately reduced soil. In these conditions, the highest microbial respiration in the soil was also measured.Učinek oksidacijsko-redukcijskega potenciala na talne mikrobe. Talni mikrobi so pomembni pri različnih procesih, ki prispevajo k rodovitnosti tal, razpoložljivosti hranil in prehrani rastlin. Delovanje talnih mikroorganizmov je odvisno od okolja, v katerem živijo. Mikrobi so lahko aerobni ali anaerobni, odvisno od njihovih potreb po kisiku. Oksidoredukcijske reakcije so v anoksičnih okoljih pogoste in mikrobi se nanje odzivajo na različne načine. Cilj te raziskave je preučiti vpliv oksidacijsko-redukcijskega potenciala tal na aktivnost talnih mikroorganizmov. Rezultati raziskave so pokazali, da so močno reducirana tla bolj ugodna za razvoj populacij bakterij kot pa populacij gliv. Ugotovljeno je bilo, da so za preživetje gliv najbolj ugodna oksidirana in zmerno reducirana tla, medtem ko lahko močno reducirana tla negativno vplivajo na njihov obstoj. Aerobne bakterije uspevajo najbolje v oksidiranih in zmerno reduciranih tleh. V teh pogojih so bile izmerjene tudi najvišje vrednosti mikrobnega dihanja v tleh.