The causes and consequences of disturbance and recovery in tropical forests are poorly known, due in large part to the lack of annual tree rings and the sparseness of long-term observations in most tropical forests. This study combines novel remote sensing technologies with careful reconstructions of forest history to understand disturbance and recovery in rain forests that differ substantially in climate and soil fertility across the Hawaiian Islands. High-precision remote measurements will yield a detailed and very broad-scale view of the structure and chemistry of these forests, and this information will be used to identify patterns of disturbance and recovery across landscapes. These patterns will be checked and refined using on-the-ground measurements of site histories (based on pollen profiles dated using lead isotopes), soil fertility, and biological diversity.
Tropical forests contribute substantially to carbon fluxes from terrestrial ecosystems, to climate, and to many other aspects of global biogeochemistry and diversity. Their dynamics are known to depend strongly upon their disturbance regimes, which in turn depend on differences among tropical forests in climate and soil fertility. The interplay between remote and on-the-ground measurements proposed here should yield new information on the dynamics of Hawaiian forests; should identify mechanisms that also operate (with modifications) in more complex continental tropical forests; and should provide new tools for understanding the dynamics of forests everywhere