4 | CONCLUSIONS
This study supports that no-tillage and straw return are essential for
improving SOC stocks, grain yields and agricultural sustainability in
the continuous wheat–maize cropping system in the southern Loess
Plateau. Soil organic C stocks increased in NT, RT and straw return
plots than in CK-SR0 plots with the highest(21.8%) in NT-SR. Straw
return, NT, and RT increased grain yields of both wheat and maize, yield
stability and sustainable yield index. Combination of conservation
tillage (e.g., NT, RT) and maize straw return can substantially increase
SOC stocks, yield stability and agricultural sustainability. Moreover,
the combinations of no-tillage with wheat straw stubbles 30–40 cm in
height and maize straw return was an effective strategy to obtain high
SOC stocks, increase grain yields of both wheat and maize and resulted
in the optimal agricultural sustainability.