Grazing your cattle just a little differently could be a win win for your operation and the environment, says a new study from the University of Alberta.
“The idea is to evaluate alternative grazing systems to see which ones are best and which ones maximize the sequestration and storage of carbon,” said ecology professor, Mark Boyce, who heads the university’s Agricultural Greenhouse Gases program.
“We could enhance beef production while maximizing conservation.”
Using effective grazing to sequester and store carbon isn’t a new concept — bison have been doing that naturally on the Great Plains for centuries. But the emphasis on it has got greater over the past five years as carbon offset credit programs have become more prevalent in Canada, said Boyce.
“There’s a huge market that’s being developed for carbon,” he said. “Industry is being taxed in various places around the world — including Alberta — for excess emissions. If we can use that tax revenue to improve our grazing management, it’s a win win.”
Through the course of the five-year study, Boyce and his team looked at how grazing management impacts carbon capture and storage and, in turn, how soil carbon can boost yields by improving soil structure, increasing nutrient and moisture retention, and reducing soil loss due to erosion.
“Climate change has been aggravated by carbon dioxide emissions into the atmosphere — the science is crystal clear on that fact,” he said. “So what do we do to reduce that?
“Well, we can reduce emissions — and that’s happening slowly — but another thing we can do is capture that carbon with photosynthesis and store it in the soil. It’s a very safe and long-term solution to excess carbon emissions.”
And so far, they’ve seen the most success simply by mimicking nature, through adaptive multi-paddock grazing.
“The idea is that you have a number of pastures or paddocks where you graze intensely with high density for a short period of time — typically three or four days — and then move the animals onto the next pasture,” he said. “You don’t revisit these pastures for a number of days, and that allows the vegetation to completely recover with no grazing pressure for an extended period of time.
“You get maximum growth rates for the plants and maximum carbon sequestration and water capture in the soil.”
Improved water capture is one of the “really clear signals” that have come out of the study, he added.
“Water infiltration into the soil is enhanced substantially using this grazing system,” he said.
“Water infiltration is really important because it provides a buffer to drought. It means you can continue grazing in an area through drought periods much better than if you had continuous grazing.”
Rotational grazing can also improve biodiversity, another key element of capturing and storing carbon. Through the summer, carbon sequestration from the atmosphere into the plants happens rapidly, but starting in the fall, soils start to lose carbon — and how much carbon is lost depends on the vegetation.
“Diversity of vegetation is very important for retaining carbon in the annual cycle,” said Boyce. “If you have a greater diversity of plants like on a native grassland, you will lose less carbon than if you have a tame pasture. Those are not nearly as effective as native grasslands.
“Native grasslands are so precious in terms of their value for carbon conservation.”
Boyce’s team estimates that, if adaptive multi-paddock grazing were adopted on just 30,000 hectares, more than one million tonnes of carbon dioxide equivalents could be sequestered over a 10-year period.
If the adoption rate was increased to 100 per cent of the livestock grasslands in Alberta — roughly 3.3 million hectares — more than 1.2 million tonnes of carbon dioxide equivalents could be sequestered every year, or 12 million tonnes over a decade.
“Grasslands are terrific places for conservation and carbon sequestration and storage,” he said. “They don’t have any downsides.”
While carbon offset credit protocols for cattle producers are still relatively limited, new protocols are in the works, and farmers can explore their eligibility for existing protocols, such as the Climate Action Reserve’s Canada Grassland Protocol.
The California-based organization bills itself as “the premier carbon offset registry for the North American carbon market.” It has vetted and accepted a grassland carbon offset protocol developed by the Canadian Forage and Grasslands Association, a key first step in monetizing carbon sequestration.
And the payment amounts could be significant, said Boyce.
“If they have grasslands that have been in permanent grassland cover for 30 years or more, they would be eligible to put their property into a carbon offset program, and they can receive up to $25 an acre just for leaving it in grassland,” he said, adding farmers can continue to graze their cattle on the land as long as they don’t convert it to cropland.
“I suspect that there are many ranchers who would view $25 an acre as a constant source of cash flow off their grasslands and a huge reward for managing their grazing properly.”
— With staff files