Doctoral Dissertation Research: A Genetic Approach to Dispersal at the Alpine Treeline Ecotone

本博士论文研究项目探讨种子传播的重要性，在高山树线交错带。一般来说，在植被过渡带的研究中，种子是在当地传播还是从遥远的种群到达的问题对于我们理解这种过渡带如何随时间变化至关重要。 如果种子只在短距离内传播，植被只能缓慢地适应环境条件的变化。 然而，如果种子长距离传播，植被带可能能够更紧密地跟踪快速变化的环境。 以前，由于在整个景观中跟踪种子的挑战，很难确定有效的传播距离。利用分子遗传学技术，可以评估树线上已建立的个体植物的起源，以确定种子生产在多大程度上是本地过程还是长距离传播的结果。这一点尤其重要，因为预计未来气候的变化将比过去快得多，研究人员必须了解物种的迁移潜力，以预测未来生态系统的样子。这项研究将调查区域和地方尺度的遗传信息的传播和流动。这项研究将结合地理和遗传学技术来检验两个假设：1）长距离传播发生在树木线上，2）克隆繁殖不是树木线种群繁殖的主要模式。 对长距离种子传播和克隆繁殖相对丰富的重要性的进一步理解将广泛地转移到其他生态交错带的研究。此外，将遗传分析纳入到空间生态学的背景下，将促进更多的研究，这种在future.This研究是一个新的地理和遗传学的整合，以回答一系列相关的问题，允许更深入地了解树木如何可能迁移下改变气候。此外，这项研究的结果将有助于更好地了解种子传播对树线动态的影响。 所产生的扩散数据将有助于改进肥尾扩散曲线的参数化，这些曲线可用于未来的研究，以模拟气候变化情景下的迁移。该项目还将用于产生与扩散、基因流动以及景观配置和地理对植物应对不断变化的生态系统的能力的重要性有关的其他假设。该小组将编写一份研究结果报告，提交给基奈国家野生动物保护区和基奈峡湾国家公园的研究和管理人员以及公众。该小组将通过避难所笔记本专栏为半岛号角报撰写一篇文章，并将在经过评审的期刊上发表，以进一步传播他们的发现。还将在会议上和通过在线数据共享传播调查结果。 该项目将促进科学教育和培训的本科生在得克萨斯州A M大学在现场和实验室工作。本科生的参与将针对代表性不足的群体。作为博士论文研究改进奖，该项目将提供支持，使有前途的学生建立一个独立的研究生涯。

This doctoral dissertation research project investigates the importance of seed dispersal at the alpine treeline ecotone. In general, in studies of vegetation transition zones, the question of whether seeds are dispersed locally or arrive from distant populations is critical to our understanding of how such transition zones may change over time. If seeds are only traveling short distances, vegetation can only adapt slowly to changes in environmental conditions. If, however, seeds are traveling long distances, vegetation zones may be able to track a rapidly changing environment more closely. Previously, it has been difficult to determine effective dispersal distances due to challenges in tracking seeds across the landscape. Using molecular genetics techniques, the origin of established individual plants at treeline can be assessed to determine to what degree seed production is a local process or the result of long distance dispersal. This is particularly important when future climates are expected to change much more rapidly than they have in the past, and it is important that researchers understand migration potential of species to predict what future ecosystems may look like. This study will investigate dispersal and flow of genetic information both regional and local scales. The research will integrate a combination of geographic and genetics techniques to test two hypotheses 1) long distance dispersal is occurring at treelines, and 2) clonal reproduction is not the dominant mode of reproduction at treeline populations. Improved understanding of the importance of long distance seed dispersal and the relative abundance of clonal reproduction will be broadly transferrable to other ecotone studies. Furthermore, the incorporation of genetic analyses into a spatial-ecology context will facilitate additional research of this kind in the future.This study is a novel integration of geography and genetics to answer a pertinent set of questions allowing for a deeper understanding of how treelines may migrate under altered climate. Additionally, the results from this study will contribute to a stronger understanding of the influence of seed dispersal on treeline dynamics in general. The dispersal data generated will contribute to improved parameterization of fat tailed dispersal curves that can be used in future research to model migration under changing climate scenarios. The project will also be used to generate additional hypotheses related to dispersal, gene flow, and the importance of landscape configuration and geography on the ability of plants to respond to changing ecosystems. The team will develop a presentation of the study's findings to present to research and management staff and to the general public at the Kenai National Wildlife Refuge and Kenai Fjords National Park. The team will write an article for the Peninsula Clarion, via the Refuge Notebook column, and will publish in refereed journals to further disseminate their findings. Findings will also be disseminated at conferences and through online data sharing. The project will foster science education and training to an undergraduate at Texas A&M University in both field and laboratory work. Undergraduate involvement will target inclusion of underrepresented groups. As a Doctoral Dissertation Research Improvement award, this project will provide support to enable a promising student to establish an independent research career.