Impact of no‐tillage on soil quality and crop yield in Asia: A meta‐analysis

No-tillage (NT) (or zero-tillage) has been widely used to mitigate the adverse effects caused by intensive tillage. However, the long-term effectiveness of NT is highly dependent on agriculture field management, soil type, and climatic conditions. NT under different climatic condition fluctuations and soil conditions has not also been considered adequately in Asia. Furthermore, the high demand for food production in Asia requires a deeper understanding of the impact of NT on soil properties and crop production. Therefore, this meta-analysis was conducted using 64 peer-reviewed articles to evaluate the effects of NT on soil organic carbon (SOC), soil carbon storage, mean weight diameter (MWD), bulk density, water-stable aggregates, water content, other soil chemical properties, and yield responses. Our results showed that NT significantly increased SOC content overall than conventional tillage (CT). Likewise, as observed at a 0-10 cm soil depth, SOC content significantly increased by 77.0% in NT compared to CT. Alternatively, although overall, NT favoured the accumulation of soil C by 53.2% than CT, and this difference was even more impressive at the 0-10 cm layer by 77.0% than CT. Moreover, overall NT significantly increased MWD, soil available P, and >2 mm aggregates than CT. In contrast, even though NT did not significantly decrease smaller than the 0.25 mm aggregates than CT in the 0-10 cm layer, NT increased exchangeable K by 81.0% than CT. Results also showed that while NT and CT had no significant effects on crop yield, NT slightly increased soybean and wheat yield, and CT increased rice and maize yield than NT. Based on these results, NT is proposed as a promising practice to enhance soil quality and is plausible to increase crop yield in Asia.