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Soil redistribution by terrace construction, as one of the most evident anthropogenic imprints on hill-slopes, may influence soil organic carbon (SOC) dynamics through re-shaping topography and altering water and oxygen availability. However, the fundamental role and mechanisms by which terrace construction affects in situ soil CO 2 emissions and its temperature sensitivity (Q 10 ) remain poorly understood. In this study, topsoil removal-addition approach was used to simulate topsoil redistribution during terrace construction. Compared with the nearby undisturbed soil, the average annual soil CO 2 emission over two years was reduced by 24% in the topsoil removed field but enhanced by 33% in the topsoil added field. The decreased soil CO 2 emission at the topsoil removed field was largely associated with the depletion of SOC stocks and microbial biomass carbon, while the increments of SOC available for decomposition at the topsoil added field contributed to its increased soil CO 2 emissions. However, the average Q 10 value in the topsoil removed field was 23% greater at seasonal scale and 28% greater at diurnal scale than that in the undisturbed soil. The increased Q 10 in the topsoil removed field is mainly due to higher aromaticity of water-extractable organic carbon (WEOC) and the domination of Actinobacteria in keystone taxa. Overall, our results show that changes in both aromaticity of WEOC and soil microbial community composition induced by soil redistribution during terrace construction may alter the response of soil CO 2 emission to elevated temperature. Our study indicates that the impact of man-made soil redistribution should not be neglected when studying regional carbon cycling., (Copyright © 2019 Elsevier B.V. All rights reserved.)