Amazon soil may store billions more tonnes of carbon than once thought

Rich soil in the Amazon cultivated over centuries by Indigenous communities may store billions of tonnes of carbon, suggesting that the rainforest plays an even larger role in stabilising the global climate than previously thought.

The soil, known as “terra preta” or “dark earth” for its distinctive colour, is formed by people spreading ash and other organic waste around settlements. It is more fertile than the region’s typically sandy, nutrient-poor soils, and stores around double the carbon. In some areas,…