Abstract: Terrestrial ecosystem carbon uptake is an important parameter to measure the surface ecology, and also a key variable of global carbon cycle. Chenzhou City of Hunan Province was selected as the study area, which is one of low-carbon city pilots and the Innovation Demonstration Zones for National Sustainable Development. Combined with multi-source data, Geostatistical Model of Soil Respiration (GSMSR), trend analysis, GeoDetector and residual analysis were used to reveal the spatial and temporal variation characteristics and driving factors of Net ecosystem productivity systematically. The results showed that: (1) Temporally, Chenzhou was a carbon pool from 2001 to 2020, with an average carbon sequestration of 5.943×106 T Ca^-1, mean value of 310.351 g Cm^-2 and an average rate of increase of 2.066 g Cm^-2a^-1. (2) Spatially, NEP changes was obvious, with higher NEP in the west and north and lower NEP in the east and south. NEP of different land types varied noticeably, among which forest was the highest (328.10 g Cm^-2), followed by grassland (318.65 g Cm^-2) and farmland (257.51 g Cm^-2). (3) The driving mechanisms of carbon fluxes in terrestrial ecosystems were diverse. NEP was positively correlated with temperature, sunshine hours, relative humidity and elevation. On the contrary, NEP was negatively correlated with precipitation and net surface radiation. In addition, the effect of two-factors interaction on NEP was obviously higher than that of the single factor. (4) Natural factors dominated the change of NEP, with an average contribution of 95.896%, while the contribution rate of land use was about 4.104%. However, in areas with intense human activities such as urban fringe, the contribution rate of land use increased significantly, with an average rate of 59.761%. The above results can help accurately grasp the spatio-temporal characteristics of the carbon sink effects of regional terrestrial ecosystems and the intrinsic driving mechanisms. Outcomes of this study provide a scientific basis for regional ecosystem management and sustainable development.