Are methane emissions from cattle causing climate change?
No. Cattle produce methane from enteric emissions (cow burbs, not farts as some believe). However it is important to note that the methane released by cows is but one small part of an ongoing greenhouse gas cycle which has existed for millions of years, whereby atmospheric carbon is sucked out of the atmosphere to grow plants, which are eaten by animals, then released as methane which breaks down back into atmospheric carbon, ready to go again.
For millions of years other ruminants such as bison, buffalo, antelopes, gazelles, giraffes, etc emitted methane in the same way as cattle do, without causing runaway climate change.
But doesn’t methane cause climate change?
Yes it does contribute, but there is a difference between the methane from cattle and methane from, for example, coal seam gas production. The cycling of carbon through cattle does not increase atmospheric carbon levels at all, as the source of the emissions is the same atmospheric carbon it returns to. For this reason, it is inaccurate to treat enteric emissions in the same way as fossil fuel emissions, which convert geologically stable carbon into atmospheric carbon which will stay in the atmosphere for millions of years. Or, for that matter, biologically stable carbon in the form of biomass or soil carbon which is released into the atmosphere when grasslands or forests are cleared to grow crops such as soy, corn and wheat.
Recent research from NASA confirms the insignificance of methane emissions from cattle, with their study showing recent increases in methane levels have come from fossil fuels and wetlands or rice farming.
Do livestock belong on grasslands?
Another issue is what would happen to the huge areas of grassland that are currently grazed by cattle. If cattle were removed and the grass is burnt, rather than eaten by cattle and turned into steak, carbon emissions (and other environmental damage) would be up to 5 times higher.
It is often not realised that grasses, animals and soils evolved together, and while the wild herds of ruminants that used to run in the grasslands have been greatly decreased, cattle can fulfil the same ecological functions while producing healthy, nutrient rich food.
In pasture based systems the manure is deposited directly onto the grass, providing a valuable source of fertiliser and not causing a methane problem as it decomposes under aerobic conditions, ie in the presence of oxygen. Trapping methane from the manure lagoons for energy production is an option, but this is an issue that industrial livestock producers need to deal with and is not a problem with cattle raised on grass.
Can red meat production benefit the environment?
It can. There is a growing body of evidence showing how beneficial red meat production can be to the environment, if managed correctly. Recent research by Texas A&M University in the US found that with appropriate regenerative crop and grazing management, ruminants not only reduce overall GHG emissions, but also facilitate provision of essential ecosystem services, increase soil carbon sequestration, and reduce environmental damage.
Other research from Michigan State University found that under Adaptive Multi Paddock Grazing (also known as Holistic Planned Grazing), more extensive (grass-based) but intensively managed beef finishing can deliver environmental benefits (such as soil carbon sequestration and other ecosystem services) with less environmental impact than intensive feedlot finishing.
Given the massive area of grasslands around the world that are not suitable for crop growing the potential for carbon sequestration is huge. The potential for grasslands to have such an impact on climate change is slowly being recognised, with recent research indicating that grazing lands generate carbon surpluses that could not only offset rural emissions but could also partially or totally offset the emissions of non-rural sectors.
On top of this research, farmers around the world have been achieving remarkable environment outcomes as a result of their grazing management, including increasing biodiversity, healthier soils and regeneration of landscapes. There are multiple examples of this around the world where grazing and improving wildlife habitats coexist:
Chris Main is a member of CPA and a grass-fed beef producer in Southern NSW. Chris has a degree in Ag Science from the University of Sydney, was an institutional stockbroker and an analyst at a funds management company.
- Climate Council website: https://www.climatecouncil.org.au/resources/australia-agriculture-climate-change-emissions-methane/