Fig. 2. Heat production (Q; mJ g1 soil) from soils amended with (A) Milli-Q water or (B) glucose over a 1.5e5 h time interval at 25 C. Mean values of four technical replicates and error bars indicate standard errors. Heat outputs are significantly different between Q without CO2-trap and Q with CO2-trap P < 0.05 (Student's t-test) when soil treatment is suffixed by *.