Researchers at Oxford University and the Swiss agricultural research institute, Agroscope, have created the most comprehensive database yet on the environmental impacts of nearly 40,000 farms, and 1,600 processors, packaging types, and retailers. This allows them to assess how different production practices and geographies lead to different environmental impacts for 40 major foods.
They found large differences in environmental impact between producers of the same product. High-impact beef producers create 105kg of CO2 equivalents and use 370m2 of land per 100 grams of protein, a huge 12 and 50 times greater than low-impact beef producers. Low-impact beef producers then use 36 times more land and create 6 times more emissions than peas.
Aquaculture, assumed to create relatively little emissions, can emit more methane, and create more greenhouse gases than cows per kilogram of liveweight. One pint of beer, for example, can create 3 times more emissions and use 4 times more land than another. This variation in impacts is observed across all five indicators they assess, including water use, eutrophication, and acidification.
For producers, the researchers present evidence in favour of using new technology. This technology often works on mobile devices, taking information on inputs, outputs, climate, and soil, to quantify environmental impacts. The technology then provides recommendations on how to reduce these impacts and increase productivity.
However, producers have limits on how far they can reduce their impacts. Specifically, the researchers found that the variability in the food system fails to translate into animal products with lower impacts than vegetable equivalents. For example, a low-impact (10th percentile) litre of cow’s milk uses almost two times as much land and creates almost double the emissions as an average litre of soymilk.
Diet change, therefore, delivers greater environmental benefits than purchasing sustainable meat or dairy.
Further, without major changes in technology that disproportionately target animal products, the researchers show that animal product-free diets are likely to deliver greater environmental benefits than changing production practices both today and in the future.
Specifically, plant-based diets reduce food’s emissions by up to 73% depending on where you live. Staggeringly, the global agricultural land would also be reduced by ~3.1 billion hectares (76%). “This would take pressure off the world’s tropical forests and release land back to nature,” says Joseph Poore.
The researchers show that we can use take advantage of variable environmental impacts to access the second scenario. Reducing consumption of animal products by 50% by avoiding the highest-impact producers achieves 73% of the previous scenarios GHG emission reduction for example. Further, lowering consumption of discretionary products (oils, alcohol, sugar, and stimulants) by 20% by avoiding high-impact producers reduces the greenhouse gas emissions of these products by 43%.
This creates a multiplier effect, where small behavioral changes have large consequences for the environment. However, this scenario requires communicating producer (not just product) environmental impacts to consumers. This could be through environmental labels in combination with taxes and subsidies.
Source: Science Daily