Abstract: 【Objective】The short-term effects of no-tillage (NT), moldboard plow (MP) and ridge tillage (RT) on the amount of soil organic carbon (SOC) in the plow layer (30 cm) of a black soil (clay loam) in Northeast China were studied. 【Method】The tillage experiment trials were established in Dehui County, Jilin Province in 2001. Using two calculating methods based on an equivalent soil depth and soil mass SOC storages under different tillages were compared. 【Result】NT practices did not lead to significant increase of SOC at the top soil (0-5 cm) compared with MP and RT practices. However, SOC contents showed a notable reduction at 5-20 cm depth. SOC storage on an equivalent soil mass in all treatments reflected the short-term effects of tillage more accurately. Three-year NT practices didn't stratify the storage of SOC on an equivalent soil mass in the plow layer on this clay loam black soil.【Conclusion】Use of no-tillage practices on this fine-textured and poor-drained black soil might not sequester more SOC than conventional tillage, at least in the short term.

Key words: tillage, soil organic carbon, equivalent soil mass, equivalent soil depth, Black soil