Eating less meat, particularly beef, recycling more waste and devoting more farmland to crops which can generate biofuels are essential if the world is to combat climate change, experts warned.
Scientists from the University of Exeter say that if today’s meat-eating habits continue, they predict that a rise in the global population could spell ecological disaster.
But changes in our lifestyle and our farming could make space for growing crops for bioenergy and carbon storage.
Though less efficient as an energy source than fossil fuels, plants capture and store carbon that would otherwise stay in the atmosphere and contribute to global warming.
Burning our waste from organic materials, such as food and manure, and any bioenergy crops we can grow while capturing the carbon contained within them could be a powerful way to reduce atmospheric carbon dioxide.
The study suggested that in order to feed a population of 9.3 billion by 2050, we need to dramatically increase the efficiency of our farming by eating less beef, recycling waste and wasting less food.
These changes could reduce the amount of land needed for farming, despite the increase in population, leaving sufficient land for some bio-energy. To make a really significant difference, however, we will need to bring down the average global meat consumption from 16.6 per cent to 15 per cent of average daily calorie intake – about half that of the average western diet.
Mr Tom Powell, a PhD student who led the project, said: “Our global agricultural system is so inefficient that we harvest about a quarter of everything that grows on the land, but only about seven to eight per cent of what we harvest ends up as food, so there are huge losses there.
“By focusing on making agriculture more efficient and encouraging people to reduce the amount of meat they eat, we could keep global temperatures within the two-degree threshold.”
Co-author Professor Tim Lenton added: “With livestock production accounting for 78 per cent of agricultural land use today, this is the area where change could have a significant impact.”