The composting of tree bark in small reactors-self-heating experiments

The effects of aeration, moisture content and temperature on the rate of decomposition of tree bark were studied in small reactors (26 litres) in the laboratory. Aeration was found to be essential in the rapid self-heating phase; thereafter vigorous aeration only served to cool the reactor. Decomposition was optimal at a moisture content of 60% with constant rates of aeration. When aeration was reduced to prevent cooling, decomposition was not appreciably different in bark with moisture contents of 60 or 70%, although higher temperatures were achieved at 60%. It was postulated that the lower thermal capacity of bark at a moisture content of 60% was partly responsible for this latter difference.