Research reveals vicious cycle of climate change, cattle diet and rising methane
Research reveals vicious cycle of climate change, cattle diet and rising methane
Scientists at the Royal Botanic Gardens, Kew, Scotland’s Rural College (SRUC) and the Senckenberg Biodiversity and Climate Research Centre, Frankfurt have published a paper today revealing an important discovery surrounding plants used to feed livestock; that plants growing in warmer conditions are tougher and have lower nutritional value to grazing livestock, potentially inhibiting milk and meat yields and raising the amount of methane released by the animals. Higher amounts of methane are produced when plants are tougher to digest – an effect of a warmer environment. Methane is a potent greenhouse gas, around 25 times better at trapping heat than carbon dioxide. More than 95% of the methane produced by cows comes from their breath through eructation (belching) as they “chew the cud”.
Dr Mark Lee, a research fellow in Natural Capital & Plant Health at the Royal Botanic Gardens, Kew who led the research says; “The vicious cycle we are seeing now is that ruminant livestock such as cattle produce methane which warms our planet. This warmer environment alters plants so they are tougher to digest, and so each mouthful spends more time in the animals’ stomach, producing more methane, further warming the planet, and the cycle continues. We need to make changes to livestock diets to make them more environmentally sustainable.”
There are several reasons why rising temperatures may make plants tougher for grazing livestock to digest. Plants have adaptations to prevent heat damage, they can flower earlier, have thicker leaves or in some cases, tougher plants can invade into new areas replacing more nutritious species – all of which makes grazing more difficult. This is a pressing concern, because climate change is likely to make plants tougher for grazing cattle, increasing the amount of methane that the animals breathe out into the atmosphere.
Read more at Royal Botanic Gardens Kew
Image: Regions in light grey are currently unsuitable for ruminant livestock, and regions beyond the range of the dataset are shaded dark grey. (Credit: Dr. Mark Lee)
