Species responses to climate change depend on environment, genetics, and interactions among these factors. Intraspecific cytotype (ploidy level) variation is a common type of genetic variation in many species. However, the importance of intraspecific cytotype variation in determining demography across environments is poorly known. We studied quaking aspen (Populus tremuloides), which occurs in diploid and triploid cytotypes. This widespread tree species is experiencing contractions in its western range, which could potentially be linked to cytotype-dependent drought tolerance. We found that interactions between cytotype and environment drive mortality and recruitment across 503 plots in Colorado. Triploids were more vulnerable to mortality relative to diploids and had reduced recruitment on more drought-prone and disturbed plots relative to diploids. Furthermore, there was substantial genotype-dependent variation in demography. Thus, cytotype and genotype variation are associated with decline in this foundation species. Future assessment of demographic responses to climate change will benefit from knowledge of how genetic and environmental mosaics interact to determine species’ ecophysiology and demography.

中文翻译：

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细胞型和基因型预测科罗拉多州地震白杨 (Populus tremuloides) 的死亡率和招募情况

物种对气候变化的反应取决于环境、遗传和这些因素之间的相互作用。种内细胞型（倍性水平）变异是许多物种中常见的遗传变异类型。然而，种内细胞型变异在确定跨环境人口统计学方面的重要性鲜为人知。我们研究了颤杨 ( Populus tremloides ))，发生在二倍体和三倍体细胞型中。这种分布广泛的树种在其西部范围内正在经历收缩，这可能与细胞型依赖的耐旱性有关。我们发现，细胞型和环境之间的相互作用推动了科罗拉多州 503 个地块的死亡率和招募。与二倍体相比，三倍体更容易死亡，并且相对于二倍体而言，在更易干旱和受干扰的地块上的补充减少。此外，人口统计学存在显着的基因型依赖性变异。因此，细胞型和基因型变异与该基础物种的衰退有关。未来对人口对气候变化的反应的评估将受益于遗传和环境镶嵌如何相互作用以确定物种的生态生理学和人口学的知识。