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Soil respiration and soil organic C content were investigated along a stand development sequence of Phoebe bournei plantations (7, 22, 38 a). The results showed that soil respiration rates of P. bournei plantations with different stand ages are characterized by a similar unimodal humpbacked trend, which peaked in summer. A significant exponential relationship between soil temperature and respiration rate was observed in the P. bournei plantations (P<0.01), while soil respiration rate showed a weak relationship with soil water content (P>0.05). With stand age development, the annual fluxes of soil respiration increased, being 1 117, 1 370 and 1 686 g⋅hm-2 a-1 at 7, 22 and 38 a stand, respectively. The Q10 value (i.e., temperature sensitivity index of soil respiration) also slightly increased with stand age. Soil organic carbon storage increased with stand development, and the mature forest is significantly higher than the middle and young forest (P<0.05). Pearson correlation analysis showed that the annual flux of soil respiration were significantly correlated with the density of surface soil organic C (P<0.01), and the organic C content of surface soil is an important determinant of the annual flux of soil respiration in these forests. [ABSTRACT FROM AUTHOR]