Journal of Cleaner Production | May 1 2023
To combat rising carbon dioxide (CO2) levels, soil organic carbon (SOC) sequestration is being explored as a solution. Deep tillage (DT) is a method that can influence SOC storage across the soil profile, but its effectiveness under different conditions in China remains unclear. Researchers from the Chinese Academy of Agricultural Sciences conducted a meta-analysis of 447 field observations to evaluate the impact of DT on SOC stocks.
The results showed that DT significantly increased SOC stocks by 7.36% compared to conventional tillage (CT). Subsoiling, a type of DT, had a greater effect (8.76%) than deep ploughing (5.85%). Subsoiling enhanced SOC in the 0-40 cm soil layer, with the greatest increase seen at the 0-10 cm depth. Deep ploughing affected SOC between the 10-40 cm depth, while both techniques had no impact below 40 cm.
Subgroup analysis revealed that factors such as high rainfall, fine soil texture, residue retention, double cropping, and increased nitrogen fertilization promoted SOC stock under DT. The study provides valuable insights for SOC management to mitigate climate change, emphasizing the need to consider environmental factors and management practices when implementing DT for enhancing SOC sequestration in different regions of China.