Scientists Assess Carbon Storage in Native Versus Non-native Hawaiian Forests
Tropical forests are important storehouses of carbon and biodiversity. In the Hawaiian Islands, relative dominance of native and non-native tree species influence patterns of forest carbon stocks and biodiversity. Forest Service scientists determined aboveground carbon in wet lowland forests of Hawaii Island. To do this at the large scales necessary to accurately capture forest heterogeneity, they collected Light Detection and Ranging (LiDAR) data across areas of interest and developed relationships between LiDAR metrics and field-based estimates of forest carbon. This approach enabled them to inventory, rather than merely sample, entire forest regions. Forest carbon mass increased with increasing lava flow age, but patterns differed between native and non-native forest stands. On the youngest lavas, native-dominated forest carbon was much lower than non-native-dominated forests, due to the presence of the non-native nitrogen-fixing trees in non-native forests. Given the large areas of early successional native forest on young lava flows, they concluded that further spread of non-native nitrogen-fixing trees would likely increase carbon storage, but would reduce the invaluable contribution of Hawaii's native ecosystems to global biodiversity.
Forest Service Partners