Margesin


Die Bodenkultur - Journal for Land Management, Food and Environment

R. Margesin and F. Schinner:

Toxicity and biodegradability of a soil conditioner

Summary

The soil conditioner Amalgerol® -Premium was investigated with regard to its toxicity, its effect on the growth of microorganisms and the biodegradability of its hydrocarbon components in soil. Concentrations up to the 1 OOO-fold of the recommended amount of application were not to be toxic in water or in aqueous soil elutriate. Only a 1 000-2 000-fold higher concentration than the recommended amount demonstrated an inhibiting effect on the growth of E. coli, V. fischeri and a mixed population of soil bacteria; the inhibiting effect decreased with time. A lower concentration resulted partially even in a stimulation of growth. In soil, the hydrocarbon content of a 1 OOO-fold concentration of the recommended amount of application was reduced by about 90 % within 8 days at 10-30° C in an open system, 50% had disappeared already after 24 h. In a closed system (gas-tight), the hydrocarbon content decreased by 24-31 % after 8 days at 10-30° C. The presence of a N-P-K fertilizer had no effect on the hydrocarbon loss in soil.

Key words:  Soil conditioner, hydrocarbons, biodegradation, toxicity, bioluminescence.