Abstract:Forest soils play a critical role in the carbon cycle and carbon sequestration at both global and local scales, and forest management practices (e.g., harvesting, burning, and thinning) influence soil carbon processes by altering organic matter quality and quantity, key microclimatic conditions, microbial communities, and other factors. However, the effects of forest management on soil carbon effluxes in different ecosystems are still largely unknown, despite being critical to estimate global carbon fluxes. Quantifying the responses of soil respiration and its components to forest management is vital to accurately evaluate forest carbon balance. Thus, an aerially seeded Pinus massoniana forest was chosen in the Three Gorges reservoir area to evaluate the effects on soil respiration of different forest management practices (i.e., control; shrub-cutting:harvesting all shrubs and removing all harvest residues. Harvest strategy 1%-15% harvest intensity and removing main harvest residues without leaves and small branches; Harvest strategy 2%-70% harvest intensity and the same harvest residue management as that in harvest 1). All experimental treatments were located in similar habitats and consisted of three 20 m×20 m plots. The treatments were conducted in October 2013. A combination of trenching and litter removing methods were employed in order to partition soil respiration into components of litter layer respiration, root respiration, and mineral soil respiration. The soil temperature, soil moisture, and rate of soil respiration and its components were observed continuously for one year (from November 2013 to October 2014) using a Li-8100 system. Management did not affect litter layer respiration within the measuring period. Root respiration in the control, shrub-cutting, harvest strategy 1, and harvest strategy 2 treatments were 1.00, 0.83, 0.86, and 1.11 μmol CO2 m-2 s-1, respectively. The mineral soil respiration of harvested stands was significantly higher than that of control and shrub-cutting stands (P < 0.05). The proportion of litter layer respiration to total respiration was not significantly influenced by forest management (18.78%-23.70%), but the contribution of root respiration to total respiration was reduced, especially in the harvest strategy 1 treatment (P < 0.05). The contribution of mineral respiration to total respiration significantly increased in harvested stands, which was mainly attributed to the decrease in total soil respiration. Management effects on soil temperature and soil moisture were only observed in the stands of harvest strategy 2. A two-factor model that included soil temperature and moisture better explained the variations in soil respiration (4.6%-59.3%) than that by a model using temperature (4.2%-59.1%) or moisture (0.3%-23.5%) alone. Other factors that influence soil respiration and its components need to be further elucidated.