Significant progress has been made at the Qiyang Station of the Institute of Agricultural Resources and Regional Planning (IARRP) in uncovering the microbiological mechanisms by which lime application reduces N₂O emissions from acidic soils. 

The findings have been published in the journal Applied Soil Ecology under the title "Mechanisms of lime-induced N₂O mitigation in acidic soils: A meta-analysis of microbial activity and substrate dynamics."

Lime application is a common practice for raising soil pH and reducing N₂O emissions in acidic soils. However, the extent of N₂O reduction and the underlying mechanisms can vary with different lime application rates and pH manipulation. This study conducted a meta-analysis of 684 sets of N₂O observation data obtained from 39 peer-reviewed studies to explore how lime application regulates functional genes and substrate concentrations to mitigate N₂O emissions in acidic soils.

The research revealed that lime application lime application reduced soil N₂O emissions by 46.63 % and raised soil pH by 27.63 % across all paired observations compared to control. Overall, lime application also increased the abundance of bacterial amoA and nosZ genes by 101.17 % and 49.63 %, respectively, while decreasing the abundance of archaeal amoA by 6.39 %.Additionally, lime application resulted in decreasing substrate NH₄⁺ and increasing NO₃− in the soil, both of which are crucial factors in reducing N₂O emissions. Lime application rate was identified as the primary factor influencing the extent of N₂O reduction. Optimal lime application rate, which adjusts soil pH to neutral, showed more pronounced effects in reducing N₂O emissions. This is primarily due to the substantial increase in nosZ gene abundance under neutral soil conditions, which promotes complete denitrification pathway.

The study highlights the importance of lime application rates and the degree of soil pH manipulation in reducing N₂O emissions from acidic soils, providing important theoretical and practical guidance for acidic soil improvement and greenhouse gas mitigation.

Kiya Adare Tadesse, a doctoral student at the Chinese Academy of Agricultural Sciences, is the first author of the study, with Researcher Zhang Huimin serving as the corresponding author. The research was supported by the National Key Laboratory of Efficient Utilization of Dryland and Semi-Arid Farmland in Northern China, the National Key Research and Development Program, the Agricultural Resource Data Service Platform for Long-term Agricultural Observations, and the National Natural Science Foundation of China.