Effects of Heating on the Microbial Populations of a Grassland Soil

Abstract

Effects of burning on soil bacteria were studied under laboratory conditions on grassland soil samples. Low intensity fire conditions were simulated in a muffle furnace (temperature of 450°C for 3 min). The number of aerobic heterotrophic bacteria and sporeformers was studied in heated and unheated samples. Immediately after burning, the number of bacteria decreased; an increase resulted however after 24 hours and after 10 days. Thirty days after treatment the number of bacteria decreased again in the treated samples, achieving values similar to the unburned soil. The laboratory procedure presented in the paper seems to be a useful approach to simulate field conditions where fire experiments are difficult to manage.