FEATURE
John Deere Director Dan Liebfried & Blue River Technology CEO Jorge Heraud walking alongside tractor
The foods that reverse climate change The way we produce food has accelerated climate change, but can sustainable production methods help to reverse it? Cattle are ruminants, meaning part of their digestive system (the rumen) is designed to ferment low-nutrition foods like grasses and leaves. Inside their digestive system, however, is an assortment of microbes that help them extract as much nutrients as they can from their food. Unfortunately, some of these microbes produce methane that is then released from the rumen. And it is here that Nielsen has turned her focus.
By Chloe Berge
I
n a new eight-part multi-platform series, Follow the Food, sponsored by CortevaAgriscience™, BBC World News and BBC.com explore the stories behind feeding the world’s ever-growing population. In a greenhouse-sized plastic box within a cattle shed in Denmark stands Daisy – farming’s hope for a sustainable future. Daisy has everything she needs. Food is carefully measured and delivered to her and water is on hand. She won’t be detained for long either, just long enough for her food to have the desired effect – we need Daisy to start burping. Overseeing the cow’s welfare is Mette Nielsen, a professor in animal sciences at Aarhus University, who explains the purpose of Daisy’s confinement. Inside the box, every burp, belch and gaseous emission can be measured. Cows’ burps are rich in methane, a greenhouse gas, and only by recording them in this way can we start to unravel how to mitigate the damage livestock farming can do to the climate. The cattle industry contributes 40% of all methane emissions from food production. They’re not the biggest contributors, that title goes to rice, but researchers are keen to clean up their act. It is part of a new wave of farming methods and hightech solutions aimed at turning farming from being a climate change problem to a part of the solution.
“It’s not the cow that produces the methane, it’s these microorganisms called Archaea,” she says. “So if we could just block this process and persuade the Archaea not to produce the methane we would basically have a climate neutral cow.” James Wong at Aarhus University
Agriculture as a whole, and the deforestation that sometimes accompanies it, contributes nearly a quarter of greenhouse gas emissions. Farming also accounts for 70% of water usage worldwide. This is not only changing the climate, but also affecting our ability to grow food in the first place. Drought, flooding, high temperatures and rising sea levels are turning productive parts of our planet into places that are incapable of growing food. But what if we could produce food in a way that not only reduces the impact farming has on the planet, but could even be beneficial for the climate.
While some might argue that giving up cattle farming altogether might be the best way to mitigate climate change, as Nielsen explains in the video below, for many people giving up beef is not a reasonable solution. Nielsen and other researchers are instead interested in the methane-inhibiting properties of an unlikely source: seaweed. Asparagopsis, a warm-water seaweed species grown in Australia, contains a compound called bromoform that when used to comprise as little as 2% of a cow’s diet, reduces the animal’s methane emissions by up to 98%. There are, however, questions over whether cows like the taste of bromoform – in some experiments livestock reduced the amount they ate after the
January - February 2021 | 27
