Recently, the innovative team of the Innovation Team of Fertilizer and Fertilization Technology at the Institute of Agricultural Resources and Regional Planning (IARRP) of the Chinese Academy of Agricultural Sciences (CAAS), has uncovered the microbial mechanisms of using hairy vetch and wheat straw in combination for reducing soil N₂O emissions. The related findings, titled "Co-incorporation of wheat straw and hairy vetch reduced soil N₂O emission via regulating nitrifier and denitrifier structure on the Qinghai plateau," have been published in the international journal "Applied Soil Ecology."

The combined utilization of leguminous green manure hairy vetch and wheat straw is an important model for improving farmland quality and enhancing the efficiency of reducing chemical fertilizer application in the Qinghai region. Due to factors such as the type of organic materials, management measures, and environmental factors, the impact of organic material returning on soil N₂O emissions varies. Previous studies have shown that the combined return of leguminous green manure and rice straw can significantly reduce N₂O emissions in paddy fields. However, whether the combined return of hairy vetch and wheat straw can reduce N₂O emissions in dryland soils and the underlying mechanisms remain unclear.

The research revealed that compared to treatments with no addition, single addition of wheat straw, or single addition of hairy vetch, the combined return of hairy vetch and wheat straw reduced N₂O emissions by 19.1%, 74.8%, and 82.8%, respectively. The combined return of hairy vetch and wheat straw reduced the microbial groups responsible for N₂O production during denitrification and increased the microbial groups responsible for N₂O reduction, thereby suppressing N₂O emissions. This study provides theoretical support for the combined return of hairy vetch and wheat straw in the Qinghai region.

Correlation Analysis between N₂O Emissions and Functional Microorganisms

Dr. Rui Liu from Gansu Agricultural University and Dr. Peng Jiang from Hunan Academy of Agricultural Sciences are the co-first authors of the paper, with Researcher Weidong Cao and Professor Qiang Chai from Gansu Agricultural University as the corresponding authors. The research was supported by the National Key Laboratory for Efficient Utilization of Northern Arid and Semi-arid Cropland, the National Key Research and Development Program during the 14th Five-Year Plan Period (2021YFD1700200), the National Natural Science Foundation of China (32072678, 32202609), and the National Green Manure Industry Technology System (CARS-22).

Original Article Link: https://doi.org/10.1016/j.apsoil.2024.105574