农田撒碎石或可大幅减少碳排放

PUTTING silicate rocks from mine waste on fields could remove up to 1.1 billion tonnes of carbon dioxide from the atmosphere annually while increasing crop yields, according to an analysis of the method’s global potential. But some question whether that figure is really achievable. Known as enhanced rock weathering, this technique accelerates the breakdown of rocks by rainwater, a natural process that, over millions of years, has transferred CO2 from the atmosphere to the ocean and helped cool the planet in hothouse- Earth periods. Farmers have been spreading ground limestone on fields for centuries to improve nutrient uptake in crops. …