New technologies will help reduce agricultural emissions – but, for now, efficiencies remain key

New Zealand’s livestock farmers are likely to be able to employ selective breeding, methane inhibitors and perhaps even methanogen vaccines to help reduce their greenhouse gas emissions within the next five to 10 years.

In the meantime, farmers wanting to make a difference to climate change need to know what their emissions are and where they come from, so they can examine every facet of their business for efficiency improvements that can maintain profitability while reducing emissions.

That’s the message from Dr Harry Clark, Director of the New Zealand Greenhouse Gas Research Centre (NZAGRC) and a member of the Interim Climate Change Committee (ICCC), following the launch of a new website ( by the research centre.  Its aim it to equip New Zealand farmers and rural professionals with the knowledge needed to assess and manage on-farm emissions and adapt to a changing environment.

The launch of the website coincided with the Government’s signal that it will implement farm-level accounting and pricing of agricultural greenhouse gas emissions by 2025.

The site initially focuses on methane, which makes up 70% of New Zealand’s agricultural emissions, but will soon expand to include information on nitrous oxide, another significant agricultural greenhouse gas, as well as strategies for adapting to climate change.

“Methane belched out by ruminant livestock such as cows and sheep is a problem for New Zealand,” Dr Clark says.

“While methane breaks down in the atmosphere a lot faster than other greenhouse gases such as carbon dioxide, every tonne emitted is 28–34 times more effective at trapping heat than a tonne of carbon dioxide, over the first hundred years after an emission occurs.

“Researchers here and overseas are therefore investigating a number of technologies that might help to reduce methane emissions by livestock in the future.”

Some animals emit less methane per unit of feed eaten than others, thanks to a smaller rumen (fore-stomach) with a distinctive population of micro-organisms. Breeding for this trait could result in a potential emissions reduction of 3–8% over 20 years.

This research is well advanced in sheep, while work in cattle is just starting, Dr Clark says.

Methanogen vaccines and inhibitors are also under development. Vaccines are being tested in the laboratory, with the goal of reducing methane emissions by 30%. An inhibitor has already been developed in the Netherlands that demonstrably reduces emissions by at least 30%.

However, in its current formulation, it must be included in every mouthful of feed – less than ideal for New Zealand’s pasture-based livestock. New formulations and alternative products are being investigated.

But until such technologies are available, Dr Clark encourages farmers wanting to further reduce their emissions to keep looking for small improvements in every aspect of their operation. He says efficiency gains already achieved across the sector mean that New Zealand’s total agricultural greenhouse gas emissions are no longer going up.

“Not all farms have the same potential to further reduce emissions,” he adds. “Some farmers have already done what they can. Others are limited by their unique climate, topography, markets and infrastructure. But there are a number of steps they might like to consider – and every small step is a step in the right direction.”

These could include getting more production from pasture to reduce reliance on imported feeds, trialling alternative forage crops, reducing animal numbers but increasing productivity per animal, achieving greater longevity in the breeding herd or flock, and applying nitrogen fertiliser using precision technologies.

Dr Clark says there’s no one-size-fits all solution, and individual farmers are in the best position to figure out how they might be able to reduce their emissions without compromising profitability – particularly as the framework for managing farm-level emissions takes shape over the coming years.

The new Farming Matters website aims to help by addressing some of the existing myths and misunderstandings about agricultural greenhouse gases and climate change and communicating the very latest advances in emissions-reduction technologies and practices. The site uses short videos and simple graphics to help explain the science and associated issues.

Ultimately, New Zealand’s emissions-reduction targets and ongoing response to climate change will be the outcome of a range of complex interacting factors, not just science and technology, Dr Clark says.

The Farming Mattersgoal  is to ensure farmers have the information they need to weigh up their options and take steps towards reducing farm-level greenhouse gas emissions.


News media earlier this week reported the Government and farming sector leaders have reached an agreement over climate change, which would see on-farm emissions accounted for by 2025.

Newshub reported: 

In an announcement on Tuesday, farming groups said they were to work with the Government to implement farm-level pricing of climate change emissions from the sector. 

It comes with the Government’s release of a consultation document, informed by the work of the Interim Climate Change Committee (ICCC).

It looks at how to bring agriculture into the emissions trading scheme, a key part of the Government’s plan to tackle climate change and reduce New Zealand’s emissions. 

Media statements from the Interim Climate Change Committee published this week can be found here  and here. 


Author: Bob Edlin

Editor of AgScience Magazine and Editor of the AgScience Blog

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