Why? One reason is because the most important source of N₂O is a use of synthetic fertilizer (chemical fertilizer). In modern agriculture, it is hard to tell farmers to 'reduce' the use of synthetic fertilizer because farmers have to use fertilizer to maintain high yield. 

Not only fertilizers but animal urine is another important source of N₂O. In a country like New Zealand, N₂O emissions from cow & sheep urine are one of the largest sources of N₂O. 

Our team are trying to propose farm management options to reduce N₂O, without reducing farm yield. In fact, reducing N₂O and increasing farm yield can be similar because both are trying to reduce the loss of nutrients from soils. 

Here are some of the ideas researched by scientists to reduce N₂O emissions without reducing fertilizer inputs. 

• Improve soil structure (high N₂O emissions are often observed from poorly managed soils)
• Timing of fertilizer application (apply fertilizers when plants need them)
• Use of coated fertilizers
• Use of microbial inoculations to reduce N₂O

These are known to reduce N₂O emissions but the reduction efficiency differs by different soil types/climate conditions. More and more studies are needed to efficiently reduce greenhouse gas emissions from soils.

 

この研究室では亜酸化窒素（N₂O）の研究を今までたくさん行ってきました。N₂Oは、畑から出る温室効果ガスです。ですからN₂O排出は減らさなければならないのですが、それは簡単ではありません。