The use of solid peroxides to stimulate growth of aerobic microbes in tundra

Abstract

Solid peroxides and peroxyhydrates degrade into a basic salt, water, and molecular oxygen when in contact with biologically active soils. Column reactors were used to quantify the extent to which three solid peroxides would stimulate growth of aerobic, heterotrophic bacteria and fungi in contaminated tundra soil. Soils in contact with a peroxide compound were incubated in column reactors at field moisture conditions at either 12 or 25°C with no mixing. After 1200-h incubations, localized concentrations of bacteria and fungi were at least 2 orders of magnitude greater in soil amended with sodium carbonate peroxyhydrate than in soil containing either calcium peroxide or magnesium peroxide. Only in soil containing sodium carbonate peroxyhydrate did microbes grow to an appreciably higher concentration than in control soil, which contained no peroxide. Stimulation of both bacterial and fungal growth occurred primarily at distances of less than 5 cm from the peroxide, suggesting that under static moisture conditions, only localized microbial growth can be expected in acidic tundra soils.