Seaweed is being used as the unlikely weapon in the battle against global warming, after research discovered a certain species can reduce cattle’s greenhouse gas contribution one burp at a time.
As pressure grows for the agricultural industry to act on climate change, new research conducted by Queensland’s James Cook University and CSIRO is having an influential effect on reducing the impact the livestock industry has on the global environment.
Attendees at the Australian Meat Processor Corporation’s Vital Ingredient Sustainability Conference in Sydney heard from CSIRO research scientist Rob Kinley about the effects seaweed is having on cows’ methane production.
In an audio presentation, Dr Kinley said by adding a type of seaweed to a cow's diet can reduce the volume of methane a cow produces by up to 99 per cent.
When people talk about a 4-5 degree celsius climate change is like an ice age in the reverse direction – these are really non-trivial changes to our climate.
- Professor Mark Howden
Species specific
The species, called Asparagopsis taxiformis, is native to Queensland’s coastal waters and can prevent methane production by reacting with vitamin B12 at the last step.
This reaction disrupts the enzymes used by gut microbes that produce methane gas as waste during digestion.
“… It would give agriculture one of the first major inputs into reducing gas emission and really dramatically make a change into the contribution to the global greenhouse gas inventory,” Dr Kinley said.
“The seaweed attacks the microbiology in the gut of cattle, sheep and goats.”
The seaweed contains a bio-active component that is a defense against bacterial infection in the ocean.
While the research is promising, Dr Kinley said the biggest challenge would be getting enough supply of the seaweed to feed cattle.
Seaweed production globally is booming with more than 25 million tonnes farmed annually.
To produce enough Asparagopsis to feed 10pc of the almost one million feedlot and 1.5 million dairy cattle in Australia would require about 300,000 tonnes a year, according to a CSIRO report.
“We are looking at foreign producers in South East Asia that are already producing million of tonnes of seaweed - not this seaweed - but as soon we can convince them it is monetarily sensible and environmentally sensible then they’ll start to switch from one type to this type of seaweed,” he said.
“This will be a big, big deal if we can bring this in.”
The findings are set to help alleviate climate change and improve agriculture’s impact on global warming.
Climate concerns
Australian National University's Climate Change Institute director, Professor Mark Howden told conference delegates that climate was a fundamental driver of Australian agriculture, directly affecting production systems and supply chains.
Last year global average temperatures were about one degree Celsius above pre-industrial levels, with the current emissions trajectory likely to reach 1.5℃ in the near future, he said.
“There’s evidence that the changes we’ve already seen in terms of climate change are having impacts on food production and food security, and that these changes are likely to increase very significantly over the next decade,” Prof Howden said.
“South west WA has lost 20pc of its growing season rainfall.
“To the north it is the opposite, where there has been a major increase in rainfall - these both have fingerprints of climate change.”
Earlier this year temperatures exceeded 1.3℃ above pre-industrial averages.
“The difference between an ice age and interglacial is about five degree Celsius,” Prof Howden said. “So when people talk 4-5 degree celsius climate change that is like an ice age in the reverse direction – these are really non-trivial changes to our climate.”
There was evidence the climate in Australia was already changing and having negative consequences for agriculture, Mr Howden said, reflective with the second consecutive year of record-breaking temperatures forecast this summer.
Extreme expectations
The impact, he said, livestock producers can expect hotter days, longer droughts and more extreme weather like cyclones, destructive storms and floods in the coming decade.
“If you look at the cool years now they are actually hotter than the hottest years that we experienced when I was born,” he said.
“We are outside the envelope of past temperature variability and we are only just at the start of climate change at the moment.”
According to Prof Howden, southern Australia was becoming hotter and drier, with more frequent extremely hot days, while in the country’s north there would likely be more frequent droughts, fires and intense tropical cyclones.
As the climate changes, so too will agriculture need to change, he said.
“We can assess the impacts of these changes and therefore develop strategies in risk and opportunities that can occur,” Prof Howden said.
CSIRO research reveals higher greenhouse gas levels are likely to have caused about half of the winter rainfall reduction in south-west Western Australia.
“If you look right now at Perth’s dams, they have already lost 90pc of their inflow – and that is with one degree change in temperature,” he said.