The study of the effects of calcium carbonate and temperature on soil organic carbon mineralization provides a theoretical basis for the objective evaluation of changes in the respiration process of yellow soil under conditions induced by global warming and lime application. In this study, a typical yellow soil in Guizhou was used as the object to study the sensitivity of 13C-labeled calcium carbonate (30 g·kg-1)to soil organic carbon mineralization and temperature sensitivity at 15, 25 ℃, and 35 ℃ using a 60-day indoor mineralization culture experiment. The results showed that the CO2 release rate from yellow soil under different treatments reached a peak on the 1st day, and then decreased rapidly, stabilizing from 15 to 60 days. The addition of calcium carbonate inhibited the mineralization of the original soil organic carbon(P < 0.01)and showed a strong negative excitation effect at the initial stage(1~10 days). The negative excitation effect was -81.0%(25 ℃), -69.3%(35 ℃), and -54.0%(15 ℃)at different temperatures. The cumulative total soil CO2 released at 35 ℃ was higher than that at 15 ℃ and 25 ℃. Increasing temperature enhanced the mineralization of soil organic carbon(P < 0.05). The amount of 13CO2 released at 25 ℃ and 35 ℃ was significantly higher than that at 15 ℃(P < 0.05), and the contribution rate to total soil CO2 release was 25 ℃(27.33%)>35 ℃(19.36%)>15 ℃(13.81%). The temperature sensitivity(Q10)of organic carbon mineralization in yellow soil ranged from 0.90 to 1.69. The addition of calcium carbonate had no significant effect on the Q10 value, but the temperature had a significant effect, and the Q10 value of the 25~35 ℃ system was higher than that of the 15~25 ℃ system. The above research suggests that in the range of 15 ℃ to 35 ℃, exogenous calcium carbonate inhibits the mineralization of organic carbon in yellow soil, and the influence of exogenous calcium carbonate on the mineralization of yellow soil organic carbon is greater than that of temperature.
