[Effect of No-tillage on Soil Aggregates in Farmland:A Meta Analysis]

Huan Jing Ke Xue. 2024 Feb 8;45(2):952-960. doi: 10.13227/j.hjkx.202303142.
[Article in Chinese]

Abstract

In order to clarify the impact of no-tillage on the quality of farmland soil aggregates in China and promote the adaptive application of no-tillage practices, a Meta-analysis was conducted by collecting data from 116 published studies. The effects of no-tillage on aggregate size distribution, mean weight diameter (MWD), and aggregate-associated C were studied. The results showed that compared with that under tillage, no-tillage significantly increased the proportion of macroaggregates (10.9%) and MWD (12.8%) and decreased the proportion of clay and silt (-15.5%) but had no significant effect on soil microaggregate and aggregate-associated C. The subgroup and Meta regression analysis showed that no-tillage significantly increased the proportion of macroaggregates in Northwest China (17.6%) and MWD in North China (15.4%). In upland and clay loam, no-tillage increased MWD by 12.6% and 18.4%, respectively. The effect of no-tillage on increasing the proportion of macroaggregates increased with the soil pH. When straw returned, no-tillage significantly increased the proportion of macroaggregates (9.6%) and MWD (11.6%), but no significant effect of no-tillage on aggregates was found after straw removal. Regarding test duration, short-term ( < 5 a) no-tillage could significantly increase the proportion of macroaggregates, whereas long-term ( > 10 a) no-tillage could improve the MWD. In different soil layers, no-tillage could only significantly improve the aggregate size distribution and MWD in topsoil (0-20 cm) but had no effect in subsoil ( > 20 cm). In summary, no-tillage could improve aggregate size distribution and stability but had no effect on aggregate-associated C. Production region, soil properties, field management methods, and other factors should be fully considered in production practice to effectively improve the quality of soil aggregates.

Keywords: Meta analysis; aggregate-associated SOC; mean weight diameter (MWD); no-tillage; soil aggregates.

Publication types

  • English Abstract