Pierre Bola, left, and Ovide Emba in a university lab where peat samples are examined and tested, in Mbandaka, Democratic Republic of Congo, Oct. 25, 2021. The area's swamps are part of the biggest network of tropical peatlands in the world -- 55,000 square miles of Central Africa that store more than 30 billion tons of carbon. (Nanna Heitmann/The New York Times)