Collaborative Research: Disturbance, Succession, and Nutrient Availability: Patterns, Mechanisms, Interactions

对热带森林的干扰和恢复的原因和后果知之甚少，这在很大程度上是由于缺乏树木的年轮，而且对大多数热带森林的长期观察也很少。这项研究结合了新的遥感技术与森林历史的仔细重建，以了解在夏威夷群岛的气候和土壤肥力差异很大的热带雨林的干扰和恢复。高精度的遥感测量将产生关于这些森林的结构和化学性质的详细和非常广泛的视图，这一信息将用于确定各种景观的干扰和恢复模式。这些模式将通过实地测量场地历史（基于使用铅同位素测年的花粉剖面）、土壤肥力和生物多样性进行检查和改进。热带森林对陆地生态系统的碳通量、气候以及全球生物地球化学和多样性的许多其他方面作出了重大贡献。已知它们的动态在很大程度上取决于它们的干扰机制，而干扰机制又取决于热带森林在气候和土壤肥力方面的差异。这里提议的远程和实地测量之间的相互作用应产生关于夏威夷森林动态的新信息;应查明在更复杂的大陆热带森林中也起作用（经过修改）的机制;并应提供了解各地森林动态的新工具。

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.