DISSERTATION RESEARCH: Phylogeny, biogeography, and population genetics of Scirpus (Cyperaceae)

了解促成植物区系多样性和分布的进化和生态过程对于这个气候快速变化时代的有效保护策略至关重要。这项研究利用最先进的 DNA 测序技术，研究了芦苇（莎草科（莎草科）湿地物种中具有重要生态意义的群体）的进化，并利用这一历史背景来预测不同分布范围的物种对气候变化的不同反应。在这个进化框架内，这项研究确定了两种濒临灭绝的、分布较窄的芦苇，并将它们与它们最密切相关的广泛亲戚进行比较，量化它们种群中存在的遗传多样性，并模拟它们对预测气候状况的反应。几十年来，气候变化一直是一个威胁，但有效的缓解策略仍处于萌芽阶段。由于分配给保护的资源有限，因此必须优先保护那些面临最大风险的物种。利用本研究提供的进化背景，本研究利用芦苇作为案例研究，以确定范围狭窄的物种在未来气候下是否比分布广泛的物种本质上更容易面临灭绝的风险。这项研究的结果将确定物种的范围是否可以作为灭绝风险的有用指标，从而可以在濒危物种变得稀有之前对其进行识别，并最终提供预测性和预防性而非反应性的保护方法。

An understanding of the evolutionary and ecological processes that have contributed to the diversity and distribution of our flora is critical for effective conservation strategies in this era of rapid climate change. Utilizing state-of-the-art DNA sequencing technologies, this research investigates the evolution of the bulrushes, an ecologically important group of wetland species in the sedge family (Cyperaceae), and utilizes this historical context to predict how species with disparate ranges may differentially respond to climate change. Within this evolutionary framework, this study identifies two endangered, narrowly distributed bulrushes and compares them to their most closely related widespread relatives, quantifying the genetic diversity present within their populations and modeling their responses to predicted climatic regimes.Climate change has been a threat for decades, yet effective mitigation strategies are still nascent. As resources allocated to conservation are limited, it is essential to prioritize by protecting those species most at risk. Using the evolutionary context afforded by this study, this research utilizes the bulrushes as a case study in order to determine if species with narrow ranges are inherently more at risk of extinction under future climates than widespread species. The results of this study will determine whether the range of a species is a useful proxy for extinction risk, thereby allowing for the identification of at-risk species before they become rare and ultimately informing a predictive and preventative, rather than reactive, approach to conservation.