A huge amount of terrestrial carbon is currently stored in the soil and the transfer of belowground carbon to the atmosphere by a warming-induced acceleration of its decomposition may lead to a strong positive feedback that may further accelerate climate change. Recently studies reported that the recalcitrant SOC components were more sensitive to temperature change, suggesting an accelerating decomposition of SOC under future warmer climate. Our incubation experiment indicated that the temperature sensitivity of SOC decomposition was not systematically correlated to the variation in SOC composition. A comparative investigation showed no significant change in SOC content in soil profile, neither the change in temperature sensitivity of soil respiration nu experimental warming. The warming effects on SOC decomposition or soil respiration and the apparent temperature sensitivity of soil respiration were significantly regulated by changes in soil moisture. A top-down analysis of global data suggested that high latitude soils are likely to be a net C sink under global climate change, suggesting that there may be important, but as yet unknown mechanisms regulating the response of ecosystems to climate change, which have not been integrated into bottom-up approaches. Combining bottom-up and top-down approaches is still a challenge to identify the possible C sinks or sources under global climate change.