Plant protein foods can provide vital nutrients using a small fraction of the land required to produce meat and dairy. By shifting to these foods, much of the remaining land could support ecosystems that absorb CO2.
For the study, published in the journal Nature Sustainability, the research team analysed and mapped areas where extensive production of animal-sourced food, which requires 83 per cent of the Earth's agricultural land, suppresses native vegetation, including forests.
"The greatest potential for forest regrowth, and the climate benefits it entails, exists in places where scaling back on land-hungry meat and dairy would have relatively minor impacts on food security," said study author Matthew Hayek from the New York University in the US.
Burning fossil fuels for energy emits CO2, warming the planet. According to the authors' findings, vegetation regrowth could remove as much as nine to 16 years of global fossil-fuel CO2 emissions, if demand for meat were to drastically plummet in the coming decades along with its massive land requirements. That much CO2 removal would effectively double Earth's rapidly shrinking carbon budget.
"We can think of shifting our eating habits toward land-friendly diets as a supplement to shifting energy, rather than a substitute," said Hayek. "Restoring native forests could buy some much-needed time for countries to transition their energy grids to renewable, fossil-free infrastructure," Hayek added.
In their report, the authors emphasise that their findings are designed to assist locally tailored strategies for mitigating climate change. "Restoring native vegetation on large tracts of low yield agricultural land is currently our safest option for removing CO2," the team said. "Reduced meat production would also be beneficial for water quality and quantity, wildlife habitat, and biodiversity," said study co-author William Ripple from Oregon State University.
Recent events have also shone a spotlight on the importance of healthy ecosystems in preventing pandemic diseases with animal origins, such as Covid-19. "Our research shows that there is potential for giving large areas of land back to wildlife," the team noted.