Natural forest expansion is a larger carbon sink than secondary forests in moist tropics (opens in new tab)

Tropical secondary forests grow back naturally after the original forest has been cleared, while degraded forests comprise regrowth within forested land that has experienced partial structural and functional loss. Both represent important carbon sinks. However, natural forest expansion into originally unforested land also occurs, and despite covering 6% more area than secondary forests in the moist tropics, its carbon sink remains unquantified. Here we quantify the above-ground carbon sink an...