Landscape genetics is an interdisciplinary field that combines tools and techniques from population genetics with the spatially explicit principles from landscape ecology. Spatial variation in genotypes is used to test hypotheses about how landscape pattern affects dispersal in a wide range of taxa. Lichens, symbiotic associations between mycobionts and photobionts, are an entity for which little is known about their dispersal mechanism. Our objective was to infer the dispersal mechanism in the semi-aquatic lichen Dermatocarpon luridum using spatial models and the spatial variation of the photobiont, Diplosphaera chodatii. We sequenced the ITS rDNA and the β-actin gene regions of the photobiont and mapped the haplotype spatial distribution in Payuk Lake. We subdivided Payuk Lake into subpopulations and applied four spatial models based on the topography and hydrology to infer the dispersal mechanism. Genetic variation corresponded with the topography of the lake and the net flow of water through the waterbody. A lack of isolation-by-distance suggests high gene flow or dispersal within the lake. We infer the dispersal mechanism in D. luridum could either be by wind and/or water based on the haplotype spatial distribution of its photobiont using the ITS rDNA and β-actin markers. We inferred that the dispersal mechanism could be either wind and/or water dispersed due to the conflicting interpretations of our landscape hypotheses. This is the first study to use spatial modelling to infer dispersal in semi-aquatic lichens. The results of this study may help to understand lichen dispersal within aquatic landscapes, which can have implications in the conservation of rare or threatened lichens.

中文翻译：

---

基因如何流动？使用空间建模和光生物标记物识别半水生地衣地衣皮的潜在扩散模式

景观遗传学是一个跨学科领域，将人口遗传学的工具和技术与景观生态学的空间明晰原理相结合。基因型的空间变异被用来检验关于景观格局如何影响广泛的生物分类的假设。地衣是霉菌和光生生物之间的共生联系，是一个对其分散机理了解甚少的实体。我们的目标是使用空间模型和光生物体双翅目Diplosphaera chodatii的空间变化来推断半水生地衣Dermatocarpon luridum中的扩散机制。我们对ITS rDNA和光生物体的β-肌动蛋白基因区域进行了测序，并绘制了Payuk湖的单倍型空间分布图。我们将Payuk湖细分为亚群，并基于地形和水文学应用了四个空间模型来推断其扩散机制。遗传变异与湖泊的地形和水通过水体的净流量相对应。缺乏按距离隔离表明该基因在湖中的流动或扩散较高。我们利用ITS rDNA和β-肌动蛋白标记，基于光生生物的单倍型空间分布，推断出D. luridum的扩散机制可能是通过风和/或水。我们推断出，由于对景观假说的解释相互矛盾，其扩散机制可能是风和/或水。这是首次使用空间模型推断半水生地衣中的扩散的研究。