Short-term Effects of Tillage Practices on Organic Carbon in Clay Loam Soil of Northeast China

A tillage experiment, consisting of moldboard plow (MP), ridge tillage (RT), and no-tillage (NT), was performed in a randomized complete block design with four replicates to study the effect of 3-year tillage management on SOC content and its distribution in surface layer (30 cm) of a clay loam soil in northeast China. NT did not lead to significant increase of SOC in topsoil (0–5 cm) compared with MP and RT; however, the SOC content in NT soil was remarkably reduced at a depth of 5–20 cm. Accordingly, short-term (3-year) NT management tended to stratify SOC concentration, but not necessarily increase its storage in the plow layer for the soil.