Concordant community similarity patterns across functional groups in subarctic plant assemblages
Concordant community similarity patterns across functional groups in subarctic plant assemblages
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亚北极植物组合中跨功能类群的一致群落相似性模式
DOI：
10.1002/ecs2.2181
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发表时间：
2018
期刊：
影响因子：
2.7
通讯作者：
C. Roland
中科院分区：
文献类型：
--
作者：
S. Stehn;C. Roland
鉴于全球生物多样性面临的威胁日益增加，确定研究不足地区物种组成沿着环境梯度变化的模式和驱动因素，对于了解生态系统的脆弱性和复原力至关重要。阿拉斯加内陆的陆生植物群落主要由三大类初级生产者-维管植物、苔藓和大型地衣组成。最近的研究表明，在该地区的各个尺度上，这三个功能组之间的物种丰富度模式存在广泛的正相关性。然而，这些功能群之间的生殖策略，扩散能力和生理适应的显着和根本的差异，促使我们调查如何社区组成和物种营业额在这些不同的群体之间的环境梯度变化。我们假设，在海拔梯度、植被类型和距离上，维管植物中的物种周转率高于产孢子隐花植物功能群，这是由于这些不同群体之间的扩散能力和栖息地偏好的时空分辨率存在潜在差异。为了解决这些问题，我们利用多阶段系统设计在阿拉斯加内陆编制了一个独特的全面的物种组成数据集。我们使用Morisita-Horn多群落相似性指数分析了每个功能组的所有植被类型和海拔带之间的群落相似性，并使用回归分析来量化组成相似性随组间地理距离衰减的速率。我们的研究揭示了一贯较高的成分变化（较低的相似性）之间的维管植物相比，苔藓和macrolichens在阿拉斯加内陆的景观梯度和空间尺度。我们还发现，衰减的相似性与距离是两个隐花植物组比维管植物。两者合计，我们的研究结果表明，功能组的扩散能力的差异，结合不同的能力，利用精细尺度的时间和空间的栖息地变化，导致减少营业额之间的苔藓和macrolichens相比，维管植物都沿着景观梯度和跨距离在阿拉斯加内陆。
In light of increasing threats to global biodiversity, identifying the patterns in and drivers of variation in species composition along the environmental gradients in understudied regions is crucial for understanding ecosystem vulnerability and resilience. Terrestrial plant communities of interior Alaska are dominated by three major groups of primary producers—vascular plants, mosses, and macrolichens. Recent work has demonstrated broad‐scale positive correlations in species richness patterns among these three functional groups across scales in this region. However, the conspicuous and fundamental differences in reproductive strategies, dispersal ability, and physiological adaptations among these functional groups prompted us to investigate how community composition and species turnover vary across environmental gradients among these disparate groups. We hypothesized that species turnover would be greater in vascular plants than for spore‐producing cryptogam functional groups across gradients of elevation, vegetation type, and distance due to underlying differences in dispersal abilities and the temporal and spatial resolution of habitat preferences among these disparate groups. To address these issues, we compiled a uniquely comprehensive species composition dataset in interior Alaska utilizing a multi‐stage systematic design. We analyzed community similarity using Morisita‐Horn index of multi‐community similarity among all pairs of vegetation types and elevation bands for each functional group and used regression analysis to quantify the rate at which compositional similarity decayed with geographical distance among groups. Our study reveals consistently higher compositional variation (lower similarity) among vascular plants as compared to mosses and macrolichens across landscape gradients and spatial scales in interior Alaska. We also found that the decay of similarity with distance was less for both of the cryptogam groups than for vascular plants. Taken together, our results suggest that differences in functional group dispersal abilities, in combination with varying abilities to utilize fine‐scale temporal and spatial habitat variation, result in reduced turnover among mosses and macrolichens as compared to vascular plants both along landscape gradients and across distance in interior Alaska.