Harvesting consequences on genetic diversity and metapopulation effective size in a spatially stratified system, the Kogaluk river drainage in northern Labrador

拉布拉多北部科加卢克河流域空间分层系统中的收获对遗传多样性和集合种群有效规模的影响

• 批准号: 430198-2012
• 负责人: Ruzzante, Daniel
• 金额: $ 8.28万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects - Group
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=516446
• 关键词: Harvesting; consequences; genetic; diversity; metapopulation

A fundamental question in evolutionary and conservation biology is how changes in habitat fragmentation (i.e., number, size, spatial arrangement and connectivity among habitat fragments) affect the maintenance of genetic diversity and the effective size of a metapopulation (metaNe). This is an issue that despite its importance for biodiversity conservation has largely been explored only from a theoretical perspective. Early models uniformly reached the somewhat paradoxical conclusion that the effective size of a fragmented system was generally higher than that of a panmictic system of equal total size, a conclusion that followed from the restrictive model assumption of equal contribution to the next generation by all subpopulations. A more recent model that includes the possibility of subpopulation extinction and recolonization demonstrates that metaNe can indeed be significantly reduced when subpopulations are allowed to contribute differentially to the next generation. This theory has remained largely unmatched by empirical data. Our goal in this project is thus to reduce this gap. We will examine the relationship between subpopulation size and diversity, gene flow (asymmetry) and metaNe in a freshwater community of three fish species differing in life histories: Lake trout (Salvelinus namaycush), longnose sucker (Catostomus catostomus), white roundfish (Prosopium cylyndraceum) and coexisting sympatrically in the Kogaluk river drainage in northern Labrador. This drainage comprises a number of hierarchically or dendritically interconnected shallow lakes on the barren grounds that drain onto a deep fjord lake. Our research using molecular markers will allow us to predict which components of the metapopulations are more likely to affect metaNe if affected and which should thus receive highest conservation priority when faced with harvesting and/or climate induced changes in landscape. Our research, conducted in collaboration with the Wildlife Division of the Newfoundland and Labrador Department of Environment and Conservation fits within the Strategic Target Area Natural Resources and Energy and research topic (b) NR Optimizing Resource Extraction, Harvesting and Renewal.

进化和保护生物学中的一个基本问题是，栖息地片断化的变化(即栖息地碎片的数量、大小、空间排列和连通性)如何影响遗传多样性的维持和集合种群的有效规模。这是一个问题，尽管它对生物多样性保护很重要，但在很大程度上只从理论角度进行了探讨。早期的模型一致地得出了一个有些自相矛盾的结论，即一个支离破碎的系统的有效规模通常高于总规模相等的泛泛系统的有效规模，这一结论源于限制性模型假设，即所有亚群对下一代的贡献是平等的。一个更新的模型包括了亚种群灭绝和重新定居的可能性，该模型表明，当允许亚种群对下一代做出不同贡献时，MetaNe确实可以显著减少。这一理论在很大程度上仍未得到经验数据的支持。因此，我们在这个项目中的目标是缩小这一差距。我们将研究三种不同生活史鱼类的淡水群落中亚种群规模与多样性、基因流动(不对称性)和MetaNe的关系：湖泊鲑鱼(Salvelinus Namaycush)、长鼻吸鱼(Catostomus Catostomus)、白圆鱼(Prosopium Cylyndraceum)以及共存于拉布拉多北部Kogaluk河流域的鱼类。这个排水系统由许多层级或树枝状相互连接的浅水湖组成，这些浅水湖位于贫瘠的土地上，排入深峡湾湖泊。我们使用分子标记的研究将使我们能够预测集合种群的哪些组成部分如果受到影响更有可能影响MetanNe，因此在面临收获和/或气候引起的景观变化时，哪些应该得到最高的保护优先级。我们的研究是与纽芬兰野生动物部和拉布拉多省环境与保护部合作进行的，符合战略目标区域自然资源和能源以及研究主题(B)自然资源的优化提取、收获和更新。