Aims To characterise the temporal variability in soil CO 2 emissions (FCO 2 ), soil O 2 influx (FO 2 ), soil water content (SWC), and soil temperature (Ts) and their relations in long-term reforested areas (30 years of conversion) in an Oxisol, Cerrado biome, Brazil. Methods The following land-use changes (Luces) were evaluated: pine (PI), eucalyptus (EU), and native species (NS) reforested areas. The molar ratio between FCO 2 and FO 2 (respiratory quotient, RQ) was calculated to better understand the process of soil metabolism. Results Soil CO 2 emission was 28% less in PI than in the other LUCs. A model including Ts, SWC, and FO 2 could explain 91 and 62% of the FCO 2 temporal variability in NS and PI, respectively. The total FCO 2 (November 2015 to May 2016) were 11.26, 10.99, and 7.97 Mg ha-1 for EU, NS, and PI areas, respectively (p < 0.05). The SWC, but not Ts, influenced the Plant Soil