Natural Products Global - May 10, 2020 - Jim Manson
Amid the debate on agricultural greenhouse gas (GHG) emissions is a heated argument about the contribution of meat and dairy farming, which often lacks nuance and leads to simplistic conclusions.
Emissions from livestock are undeniably very large. The United Nations Food and Agriculture Organization (FAO) says they account for 14.5% of all GHG emissions. But different livestock production systems produce very different emission levels, something that has been under acknowledged in a number of high profile academic reports on the subject.
Recently, Emma Hartelius, a KRAV-certified organic livestock farmer from Västergötland in southwest Sweden, decided to find out for herself her own farm’s climate impact – and whether carbon neutrality was an achievable aim.
Using the Greppa Nutrition calculation model, Hartelius recorded the full range of inputs used across the farm, taking into account plant cultivation, soil type, crops, manure usage, harvests and harvest losses, together with detailed information on livestock production (animal types, breed, feed, fertiliser and slaughter age). While this particular model doesn’t take into account the natural features or enhanced biodiversity of organic farming, it does factor in the amount of carbon sequestered, which is generally higher in regenerative organic systems.
Writing about the results of her study for the ‘future food’ website AGFO, Hartelius says “When all parts of the calculation had been done, our meat came in at 15 kilos of CO2e (carbon dioxide equivalent) per kilo – without counting carbon deposits in the soil. When included, we reduced to 14 kilos of CO2e per kilo of meat. Swedish beef is at an average of 26 kilos CO2e per kilo and beef from Brazil at about twice that, according to the WWF.”
“Our farm conducts active forestry and annually sequesters 1,700 tonnes of CO2e. If we took that into account, we’d be climate positive straight away”
Hartelius’s results showed that the largest emissions from her farm come from the natural processes of animal digestion and emissions from the soil. Animal digestion accounts for one third, and nitrous oxide from soil and manure and carbon dioxide from the soil account for half of the emissions. Diesel used by farm vehicles and machinery accounted for just 3% of the 572 tonnes of CO2e that the farm emits per year. This finding had led to her conclude that reducing mineral fertilisers in agriculture should be prioritised over cutting fuel use. On her own farm she avoids use of mineral fertiliser entirely, relying on her animals’ manure.
Hartelius says she finds it hard to believe that agriculture can be completely carbon neutral – but adds that it depends on how you do the calculations. She explains: “Our farm conducts active forestry and annually sequesters 1,700 tonnes of CO2e. If we took that into account, we’d be climate positive straight away.”