The Principal Research Officer at Teagasc, Gary Lanigan, has commented that the first step towards reducing GHG emissions in the agricultural sector is tackling nitrogen use. Lanigan led research on a Marginal Abatement Cost Curve (MACC) for greenhouse gas (GHG) in Irish agriculture.
He added that it will be “very challenging” to lower emissions by 25% through science alone, saying that, “There are two ways you can increase the total amount of mitigation — by upping the adoption rates of measures already proposed, or by coming up with new methods.”
“Two thirds of our soils are at the wrong lime levels, so if we can get another third to the right level, you will get more nitrogen mitigation. The adoption of lime is happening — about 1.3 million tonnes of lime was spread last year, but when you spread that lime, you are supposed to decrease your fertiliser application, but fertiliser application actually went up last year,” he said.
“Changing the message and attitude to nitrogen has got to be the thing we lead with. Step one is to stop putting out unnecessary nitrogen and particularly stop putting out unnecessary amounts of CAN.”
In his view, hitting all the nitrogen measures would take out about 1.5m tonnes or more. “It’s not a silver bullet, but it will make a huge impact. We have a 25% target and that means we need to be one million tonnes down by 2025. So that’s where you start – you start with nitrogen.”