Details

Autor(en) / Beteiligte

• Hiis, Elisabeth G
• Vick, Silas H W
• Molstad, Lars
• Røsdal, Kristine
• Jonassen, Kjell Rune
• Winiwarter, Wilfried
• Bakken, Lars R

Titel

Unlocking bacterial potential to reduce farmland N 2 O emissions

Ist Teil von

• Nature (London), 2024-05

Ort / Verlag

England

Erscheinungsjahr

2024

Beschreibungen/Notizen

• Farmed soils contribute substantially to global warming by emitting N O (ref.  ), and mitigation has proved difficult . Several microbial nitrogen transformations produce N O, but the only biological sink for N O is the enzyme NosZ, catalysing the reduction of N O to N (ref.  ). Although strengthening the NosZ activity in soils would reduce N O emissions, such bioengineering of the soil microbiota is considered challenging . However, we have developed a technology to achieve this, using organic waste as a substrate and vector for N O-respiring bacteria selected for their capacity to thrive in soil . Here we have analysed the biokinetics of N O reduction by our most promising N O-respiring bacterium, Cloacibacterium sp. CB-01, its survival in soil and its effect on N O emissions in field experiments. Fertilization with waste from biogas production, in which CB-01 had grown aerobically to about 6 × 10 cells per millilitre, reduced N O emissions by 50-95%, depending on soil type. The strong and long-lasting effect of CB-01 is ascribed to its tenacity in soil, rather than its biokinetic parameters, which were inferior to those of other strains of N O-respiring bacteria. Scaling our data up to the European level, we find that national anthropogenic N O emissions could be reduced by 5-20%, and more if including other organic wastes. This opens an avenue for cost-effective reduction of N O emissions for which other mitigation options are lacking at present.