We incubated intact peat cores from depth intervals of 5-15, 15-25, 25-35, and 35-45 cm from ombrotrophic bog, poor fen, and beaver pond margin sections of a cool-temperate peatland. CO2production was measured over 12-day incubation periods at 4 and 14 °C and under oxic and anoxic conditions. Rates ranged from 0.06 to 0.66 mg CO2g−1dry peat d−1under oxic conditions and from 0.002 to 0.098 mg CO2g−1d−1under anoxic conditions, and rates generally decreased with depth in the profiles. When expressed on a volumetric basis, production rates ranged from 0.3 to 23.4 g CO2m−3d−1, and there was much less variation in CO2production rates within profiles because the bulk density of peat increased with depth. The Q10quotient, between 4 and 14 °C, ranged from 1.0 to 7.7, depending on sample and incubation conditions, with an average of 2.0 for oxic and 2.7 for anoxic conditions. Oxic:anoxic ratios averaged 7:1, 16:1, and 12:1 for the bog, poor fen, and beaver pond margin samples, respectively. Degree of decomposition (von Post index) was the substrate property most strongly correlated with CO2production. Based on temperature and incubation data for the peat profiles to a depth of 45 cm, annual decomposition values (k) ranged from 0.016 to 0.060 yr−1under oxic conditions and from 0.001 to 0.007 yr−1under anoxic conditions. A model of CO2emission from the three sites, based on the incubation data and thermal and water table regime, gave good agreement with measuredin situCO2emission rates (r2= 0.72,n= 18), although summer emission rates were underpredicted, possibly because of the absence of a root production component in the incubations or because of underestimation of CO2production rates in field conditions above the water table.