School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia.
Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Sydney, NSW, Australia.
Glob Chang Biol. 2021 May;27(10):2200-2212. doi: 10.1111/gcb.15534. Epub 2021 Feb 16.
Globally, critical habitats are in decline, threatening ecological, economic and social values and prompting calls for 'future proofing' efforts that enhance resilience to climate change. Such efforts rely on predicting how neutral and adaptive genomic patterns across a species' distribution will change under future climate scenarios, but data is scant for most species of conservation concern. Here, we use seascape genomics to characterise genetic diversity, structure and gene-environmental associations in a dominant forest-forming seaweed, Phyllospora comosa, along its entire latitudinal (12° latitude), and thermal (~14°C) range. Phyllospora showed high connectivity throughout its central range, with evidence of genetic structure and potential selection associated with sea surface temperatures (SSTs) at its rear and leading edges. Rear and leading-edge populations harboured only half the genetic diversity of central populations. By modelling genetic turnover as a function of SST, we assessed the genomic vulnerability across Phyllospora's distributional range under climate change scenarios. Despite low diversity, range-edge populations were predicted to harbour beneficial adaptations to marginal conditions and overall adaptability of the species may be compromised by their loss. Assisted gene flow from range edge populations may be required to enhance adaptation and increase resilience of central and leading-edge populations under warming oceans. Understanding genomic vulnerability can inform proactive restoration and future-proofing strategies for underwater forests and ensure their persistence in changing oceans.
全球范围内，关键生境正不断减少，这威胁到了生态、经济和社会价值，并促使人们呼吁采取“面向未来”的措施来增强对气候变化的适应能力。这些措施依赖于预测物种分布范围内的中性和适应性基因组模式在未来气候情景下将如何变化，但对于大多数受到保护关注的物种来说，数据仍然匮乏。在这里，我们使用景观基因组学来描述整个纬度（12°纬度）和温度（~14°C）范围内占主导地位的森林形成海藻 Phyllospora comosa 的遗传多样性、结构和基因-环境关联。Phyllospora 在其中心区域表现出高度的连通性，有证据表明与海表温度（SST）有关的遗传结构和潜在选择存在于其后缘和前缘。后缘和前缘种群仅拥有中心种群遗传多样性的一半。通过将遗传更替建模为 SST 的函数，我们评估了 Phyllospora 分布范围内的基因组在气候变化情景下的脆弱性。尽管多样性较低，但预测边缘种群可能具有对边缘条件的有益适应，而物种的整体适应能力可能会因它们的丧失而受到损害。需要从边缘种群辅助基因流，以增强对变暖海洋的中心和前缘种群的适应能力和恢复力。了解基因组的脆弱性可以为水下森林的主动恢复和面向未来的策略提供信息，并确保它们在不断变化的海洋中得以持续存在。
