Doctoral Dissertation Research: Evaluating whitebark pine (Pinus albicaulis) resistance and resilience to fire and insect outbreaks

这一博士论文项目将研究一种具有重要文化和生态价值的树种--白皮松如何在生理上适应山地环境中高海拔亚高山森林中的火灾等干扰。野火、昆虫暴发和疾病在创造白皮松(WBP)森林在高海拔生态系统中持续存在的条件方面发挥了重要作用。亚高山森林树种已经开发出不同的策略来生存这些干扰，包括生长厚厚的树皮以躲避火灾，以及驱逐山松甲虫等昆虫的树脂管道。这项研究将评估WBP树在受到干扰时所使用的不同策略。这些结果将为不同的生长和防御策略提供洞察力，这些策略可能有助于提高存活率，促进WBP的建立和持续。更好地了解WBP树是如何应对干扰的，将为负责维护未来WBP林的自然资源管理者提供宝贵的信息。此外，该项目将支持一名博士生的培训。火、虫暴发和病害对WBP森林的长期建立和持续起着重要作用，然而，对于WBP树在不同干扰历史下的生长机制缺乏研究。我们的研究将通过检测三个不同高海拔森林地点的200多棵树的生长(年轮宽度)和防御特征(导管解剖和树脂化学)来评估野火和山松甲虫活动对WBP生理的影响。这项研究将提供有关WBP应对亚高山森林中日益增多的多种干扰的特征和条件的重要信息。这项工作对于未来维持具有重要生态意义的WBP森林的恢复工作非常重要。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This doctoral dissertation project will investigate how a culturally and ecologically important tree species, whitebark pine (Pinus albicaulis), has physiologically adapted to disturbances such as fire in high-elevation subalpine forests in mountain environments. Wildfire, insect outbreaks and diseases play an important role in creating conditions in which whitebark pine (WBP) forests can persist in high-elevation ecosystems. Subalpine forest tree species have developed different strategies to survive these disturbances including the growth of thick bark to survive fires and resin ducts that expel insects such as mountain pine beetles. This research will evaluate the different strategies used by WBP trees to survive disturbances. The results will provide insights into different growth and defense strategies that may be beneficial to increasing survivorship and promoting WBP establishment and persistence. Better understanding how WBP trees respond to disturbance will provide valuable information for natural resource managers tasked with maintaining WBP stands into the future. Furthermore, this project will support the training of a doctoral student. Fire, insect outbreaks and disease play an important role in the long-term establishment and persistence of WBP forests, however, research is lacking to understand the growth mechanisms that WBP trees use to persist under different histories of disturbance. Our research will assess the influence of wildfire and mountain pine beetle activity on WBP physiology by examining growth (ring-widths) and defense characteristics (duct anatomy and resin chemistry) for over 200 trees at three different high-elevation forest sites. This research will provide important information on the characteristics and conditions under which WBP respond to multiple disturbances that are increasing in subalpine forests. This work is important for restoration efforts to sustain ecologically important WBP forests into the future.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.