EFFECT OF MINERAL COMPOUNDS ON THE RESPIRATION ACTIVITY OF THE MICROBIAL COMMUNITY OF RAISED BOGS

The effect of mineral supply, pH, and drying-rewetting on the microbia l respiration activity (RA) in peat samples from a raised bog was stud ied. Neutralization of the acidity of peat with phosphate buffer was f ound to stimulate respiration of microorganisms only for a period as s hort as 3 days. A significant decline in RA was observed upon addition of Ca(No-3)(2) or a mixture of (NH4)(2)SO4 and KH2PO4. Drying-rewetti ng of peat also caused RA to decline after a transient increase. To ex plain the effects observed, it is assumed that the community of hetero trophic microorganisms in the peat of raised bogs is subject to multip le limitation (by the sources of carbon and energy and other biogenic elements) and that the addition of deficient elements to peat brings a bout metabolic inhibition arising from disturbed pH balance.