An international research programme led by New Zealand scientists has revealed a breakthrough in their fight to reduce agricultural greenhouse emissions.
After two years of work, researchers from AgResearch and Otago University, along with researchers from Australia, the United States and Japan, have discovered which bacteria in a sheep's first stomach produce hydrogen as part of the digestion process, and the specific enzymes inside the bacteria that are responsible.
They've also found which organisms use the hydrogen as a food source in the production of methane.
"Personally, it's very pleasing because it's been a good piece of work which is going to be hopefully relevant and applicable to the methane problem in New Zealand," study lead AgResearch principal scientist Dr Graeme Attwood said.
Annually, methane emissions account for over five per cent of the world's greenhouse gases, which cause global warming.
In New Zealand, the gas makes up a third of the country's emissions.
"It's a different angle of attack and it's got a good chance of working so, yes, I think it's a realistic opportunity to reduce methane," Dr Attwood said.
Existing DNA analysis was matched with high and low methane-producing sheep to show the pathway for hydrogen inside a sheep's first stomach (rumen.)
The amount of methane the sheep belched out after eating was measured in gas chambers.
While other research is working on directly stopping methane-producing microbes from functioning, the focus of this study is now reducing methane production by finding a way to prevent hydrogen being created or by diverting hydrogen to other organisms that don't create methane.
Creating a vaccine or pill that could do that is up to six years away.
“There are things we could be doing much more quickly and dairy farming in New Zealand, there are problems around a lot of things beyond climate change – water quality, fertiliser use… demand for irrigation,” said environment researcher James Renwick.
Mr Renwick said the country needs to reduce the number of cattle on intensive dairy farms.
“I think Government could actually be looking to push things back in the other direction, it could reduce our emissions almost overnight by just making some changes in the way we produce food, our agriculture sector,” he said.
“There are options that are much less carbon-intensive than dairy farming.”
Agricultural Minister Damien O’Connor said he’s pleased with the rate of progress on reducing the effects of agriculture in New Zealand and is welcoming the latest discovery from the Global Research Alliance on Agricultural Greenhouse Gases.
“We’re moving, there are breakthroughs like different pasture species that can also help reduce methane so we’re not leaving any stone unturned…,” he told 1 NEWS.
Mr O’Connor said an increasing population requires an increase in production.
“New Zealand, if it can do both, that is increase production and reduce emissions, we can help the world feed itself.”