As deforestation and forest degradation proceeding in tropical forests, soil properties as well as soil organic carbon (SOC) stock are also responding to above ground biomass (AGB) loss. In spite of the limited input of plant debris, how changes of soil chemical properties function in the decrease of SOC stock is left unclear. In this study, we established three 50-year scenarios simulating different logging and recovery processes utilizing CENTURY model, aiming at revealing how soil pH and water movement affect SOC stock under different recovery status. The model was parameterized with published data collected in Deramakot Forest Reserve, Malaysian Borneo. The three scenarios simulated pristine forests, impeded and pseudo forest recovery after harvest respectively, where soil pH and water movement were adjusted artificially according to observation.
We compared the general trends and final outputs of monthly total SOC among three scenarios, finding that soil carbon stock generally changes in line with AGB but soil pH significantly limited SOC stock even after forest recovery. The model did not reasonably reveal how soil water movement participated in the process. The results implied that soil redox environment was another essential factor for predicting responses of SOC to different logging intensities.