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

人们对热带森林的干扰和恢复的原因和后果知之甚少，这在很大程度上是因为缺乏年轮，而且大多数热带森林的长期观测稀少。这项研究将新颖的遥感技术与仔细重建森林历史相结合，以了解夏威夷群岛气候和土壤肥力差异很大的热带雨林的干扰和恢复情况。高精度的遥感测量将对这些森林的结构和化学成分产生详细和非常广泛的看法，这些信息将被用来确定各种景观的干扰和恢复模式。这些模式将使用现场历史(基于使用铅同位素测得的花粉剖面)、土壤肥力和生物多样性的实地测量进行检查和改进。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都有很大贡献。众所周知，它们的动态很大程度上取决于它们的干扰机制，而这些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。这里提出的遥测和实地测量之间的相互作用应能提供有关夏威夷森林动态的新信息；应查明在更复杂的热带大陆森林中也有作用(经修改)的机制；并应为理解各地森林的动态提供新的工具。

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.