MICROCALORIMETRIC STUDY OF THE EFFECT OF TEMPERATURE ON MICROBIAL ACTIVITY IN SOILS

The effect of temperature on the microbial degradation of glucose in s oil was studied in a conduction-type microcalorimeter. The microbial g rowth constant, mu, was calculated from the heat evolution associated with the degradation of carbon source, and the power-time curves recor ded at different temperatures. The activation energy was obtained from an Arrhenius-type equation and was found to be 39.57 kJ mol(-1). Base d on the fact that the pattern of bacterial growth is similar to the t ransition-state theory for chemical process, values of activation entr opy, Delta S-not equal, and activation free energy, Delta G(not equal) , were calculated. These data can be very useful when studying bacteri al growth thermodynamic properties in soil. (C) 1997 Elsevier Science B.V.