RUI: Canopy Tree Mortality and Regeneration in Southern Appalachian Gaps Sampled Thrice

这项研究将提高对原始森林中树木死亡更替动态的理解。具体目标是调查冠层树木的种类和大小特异性生长和死亡率，与冠层树木死亡相关的林隙特征，林隙中的植被发育以及死树的动态。这些目标将通过在阿巴拉契亚南部的原始森林中重新采样树冠树和间隙植被来实现。关于生长和死亡率的数据集的组合将使森林的更替能够得到在其他地方不可能得到的研究。这些森林是美国东部森林在物种组成和生态系统特性方面可能处于长期平衡的最好例子。它们将作为解释其他东部森林变化的有价值的对照；例如，确定人类活动或气候变化是否引起了比平常更多或不同的变化。本研究还将展示物种生活史的不同方面（例如，冠层寿命与间隙捕获能力）如何导致它们在不同森林中共存。分析结果将直接有助于建立预测全球变化影响所需的知识库。

This research will improve understanding of the dynamics of tree death replacement in old-growth forests. Specific goals are to investigate the species-and size-specific growth and death rates of canopy trees, gap characteristics associated with canopy tree death, vegetation development in gaps, and the dynamics of dead trees. These goals will be met by resampling canopy trees and gap vegetation originally sampled in old-growth forests of the southern Appalachians. The combinations of data sets on growth and mortality will allow turnover in the forests to be studied to a degree impossible elsewhere. These forests are the best example in the eastern United States of forests likely to be in long-term equilibrium in terms of species composition and ecosystem properties. They will serve as a valuable control for interpreting changes in other eastern forests; e.g., determining whether human activity or changing climate is causing more or different changes than usual. This study also will demonstrate how different aspects of species life histories (e.g., canopy longevity versus gap-capturing ability) can result in their coexistence in diverse forests. Findings from the analysis will contribute directly to the knowledge base needed to predict the effects of global change.