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

这项研究将提高对老树林中树木死亡更替的动态的理解。具体目标是调查树种和大小特定的树冠树的生长和死亡率、与树冠树死亡相关的林隙特征、林隙中的植被发展以及死亡树木的动态。这些目标将通过重新采样树冠树和林隙植被来实现，这些树木和林隙植被最初是在阿巴拉契亚山脉南部的古老森林中采样的。有关生长和死亡的数据集的组合，将使人们能够在其他地方无法达到的程度上研究森林的周转。这些森林是美国东部在物种组成和生态系统性质方面可能处于长期平衡状态的森林的最佳范例。它们将作为解释其他东部森林变化的宝贵控制；例如，确定人类活动或气候变化是否造成了比平时更多或不同的变化。这项研究还将展示物种生活史的不同方面(例如，树冠寿命与林隙捕获能力)如何导致它们在不同的森林中共存。分析结果将直接有助于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.