Group for Limnology and Environmental Biotechnology, Area of Ecology, Universidad de León, Campus de Vegazana, León, Spain.
Geography Research Unit, University of Oulu, P.O. Box 3000, FI-90140 University of Oulu, Finland.
Sci Total Environ. 2019 Nov 25;693:133616. doi: 10.1016/j.scitotenv.2019.133616. Epub 2019 Jul 27.
Metacommunity ecology has broadened considerably with the recognition that measuring beta diversity beyond the purely taxonomic viewpoint may improve our understanding of the dispersal- and niche-based mechanisms across biological communities. In that perspective, we applied a novel multidimensional approach including taxonomic, functional and phylogenetic data to enhance our basic understanding of macrophyte metacommunity dynamics. For each beta diversity metric, we calculated the mean overall value and tested whether the mean value was different from that expected by chance using null models. We also employed evolutionary and spatially constrained models to first identify the degree to which the studied functional traits showed a phylogenetic signal, and then to estimate the relative importance of spatial and environmental effects on metacommunity structure. We first found that most individual ponds were inhabited by species that were merely random draws from the taxonomic and phylogenetic species pool available in the study region. Contrary to our expectations, not all measured traits were conserved along the phylogeny. We also showed that trait and phylogenetic dimensions strongly increased the amount of variation in beta diversity that can be explained by degree of environmental filtering and dispersal limitation. This suggests that accounting for functional traits and phylogeny in metacommunity ecology helps to explain idiosyncratic patterns of variation in macrophyte species distribution. Importantly, phylogenetic and functional analyses identified the influence of underlying mechanisms that would otherwise be missed in an analysis of taxonomic turnover. Together, these results let us conclude that macrophyte species have labile functional traits adapted to dispersal-based processes and some evolutionary trade-offs that drive community assembly via species sorting. Overall, our exploration of different facets of beta diversity showed how functional and phylogenetic information may be used with species-level data to test community assembly hypotheses that are more ecologically meaningful than assessments of environmental patterns based on the purely taxonomic viewpoint.
随着人们认识到，超越纯粹分类学观点来衡量β多样性可以增进我们对生物群落中扩散和生态位机制的理解，元生物群落生态学已经得到了极大的拓展。从这个角度出发，我们应用了一种新的多维方法，包括分类学、功能和系统发育数据，以增强我们对大型植物元生物群落动态的基本理解。对于每个β多样性度量，我们计算了总体平均值，并使用零模型检验平均值是否与随机预期值不同。我们还采用了进化和空间约束模型，首先确定所研究的功能特征表现出系统发育信号的程度，然后估计空间和环境效应对元生物群落结构的相对重要性。我们首先发现，大多数单个池塘中栖息的物种只是从研究区域内可用的分类和系统发育物种库中随机抽取的物种。与我们的预期相反，并非所有测量的特征都沿着系统发育保持保守。我们还表明，特征和系统发育维度强烈增加了β多样性的变化量，这些变化量可以通过环境过滤和扩散限制的程度来解释。这表明在元生物群落生态学中考虑功能特征和系统发育有助于解释大型植物物种分布的特有变化模式。重要的是，系统发育和功能分析确定了潜在机制的影响，否则在分类学周转率分析中会忽略这些影响。总之，这些结果使我们得出结论，大型植物物种具有适应扩散过程的不稳定功能特征和一些进化权衡，这些特征通过物种分类来驱动群落组装。总体而言，我们对β多样性不同方面的探索表明，功能和系统发育信息如何与物种水平数据一起用于测试比基于纯粹分类学观点评估环境模式更具生态意义的群落组装假设。
