Genetic and evolutionary effects of anthropogenic and natural disturbances, and minimum viable population size in forest trees

遗传多样性被广泛认为是物种和种群可持续性的基础。它为物种和个体的适应、进化和生存提供了原材料，特别是在变化的环境和疾病条件下。由于树木通常是森林生态系统的核心物种，它们的遗传多样性具有特殊的意义。人为活动(如森林采伐、农业、城市化)和自然干扰(如森林火灾)可影响林木种群的遗传多样性和进化动态。了解遗传多样性、交配系统、自然种群固有的生殖适宜性和基因扩散、森林管理做法、碎片化和森林火灾对这些参数的影响以及最小可存活种群数量，对于了解形成遗传多样性的机制和制定有效的森林遗传资源保护和可持续管理战略至关重要。我的研究目标是更深入地了解人类活动和自然干扰对遗传和进化的影响，以及在林分和景观水平上维持种群遗传多样性、进化动态和可持续性的机制，以及林木中的MVP。拟议的研究将建立在我在这一领域对几种云杉和松树的持续研究基础上。将确定森林碎片化、作业森林采伐系统和实验性森林采伐系统以及自然森林火灾和实验性森林火灾的遗传影响。DNA标记、候选基因和/或等位酶将用于确定遗传多样性、交配模式和基因扩散参数以及MVP。这些参数与森林破碎化程度、采伐和火灾强度、种群大小和密度以及适合性特征的关系将被确定。所提出的研究对于理解维持或影响遗传多样性、生存能力和适合度的过程以及微观进化和集合种群进化动力学具有基本的种群遗传和进化意义。这对森林遗传资源的保护、管理和恢复具有重要的应用意义。

Genetic diversity is widely recognized as the foundation of sustainability of species and populations. It provides the raw material for adaptation, evolution and survival of species and individuals, especially under changed environment and disease conditions. Since trees are normally the keystone species of the forest ecosystems, their genetic diversity has a special significance. Anthropogenic activities (such as forest harvesting, agriculture, urbanization) and natural disturbance (such as forest fires) can affect genetic diversity and evolutionary dynamics of forest tree populations. Knowledge of genetic diversity, mating system, reproductive fitness and gene dispersal inherent in natural populations, impacts of forest management practices, fragmentation and forest fires on these parameters, and minimum viable population size (MVP) is essential to understand the mechanisms that shape genetic diversity, and to devise effective strategies for conservation and sustainable management of forest genetic resources. My research goal is to gain deeper understanding of the genetic and evolutionary impacts of human activities and natural disturbance and the mechanisms that maintain genetic diversity, evolutionary dynamics and sustainability of populations at the stand and landscape levels, and MVP in forest trees. The proposed research will build upon my continuing studies in this area on several spruce and pine species. Genetic impacts of forest fragmentation, operational and experimental forest harvesting systems, as well as natural and experimental forest fires will be determined. DNA markers, candidate genes and/or allozymes will be used to determine genetic diversity, mating patterns and gene dispersal parameters, and MVP. Relationships of these parameters with the degree of forest fragmentation, harvesting and fire intensities, population size and density, and fitness traits will be determined. The proposed research has fundamental population genetic and evolutionary significance for understanding processes that maintain or affect genetic diversity, viability and fitness, as well as microevolutionary and metapopulation evolutionary dynamics. It has applied significance for conservation, management and restoration of forest genetic resources.