ACETATE SYNTHESIS IN SOIL FROM A BAVARIAN BEECH FOREST

Soil obtained from a beech forest formed significant amounts of acetat e when incubated in a bicarbonate-buffered, mineral salt solution unde r anaerobic conditions at both 5 and 20-degrees-C (21 and 38 g of acet ate per kg [dry weight] of soil, respectively). At 20-degrees-C, follo wing an 18-day lag period, rates of 0.07 mmol of acetate synthesized p er g (dry weight) of soil per day were observed. Acetate was not subje ct to immediate turnover; methane and hydrogen were not formed during the time intervals (5-degrees-C, 335 days; 20-degrees-C, 95 days) eval uated. The synthesis of acetate from endogenous materials was coincide nt with acetogenic potentials, i.e., the capacity to catalyze the H-2- dependent synthesis of acetate. Hydrogen consumption was not directed towards the synthesis of methane. Collectively, these results suggest that acetogenesis may be an underlying microbial activity of this fore st soil.