But they help to make them more vulnerable. This lets the sunlight strike through to the forest floor, where it dries out the organic debris created by the logging. And fires leave the surviving trees more susceptible to future blazes. The researchers say the area of surface fires may be much larger than usual during severe droughts. These so far unreported forms of forest loss, the researchers say, imply a need to look again at climate change calculations.
Carbon dioxide is the principal gas caused by human activity that is implicated in global warming.
But they found that only about a tenth of the area classified as forest actually supported undisturbed forest. But this monitoring needs to be expanded to include forests affected by logging and surface fire if it is to accurately reflect the full magnitude of human influences on tropical forests. The BBC is not responsible for the content of external internet sites.