Use of Microcalorimetry for the Characterization of Microbial Activity in Soil

Abstract

A methodological study of the calorimetric determination of heat effects in soil was carried out. Homogenized soil samples of different types were enclosed in 10 ml calorimetric ampoules. Stimulation of the microbial activity by addition of glucose was investigated, as were the effects of heat treatment and .alpha. irradiation, and the inhibition of the microbial activity with streptomycin and actidione. During the work, a new ampoule technique was developed. By use of plastic insert ampoules, calorimetric measurements could be made on individual soil samples during long periods of time (months) without any significant changes in the concentrations of CO2 or O2 in the sample. Soil calorimetry is in an early stage of development, but there are no particular difficulties involved in performing precise microcalorimetric measurements on soil samples.