Bañares-de-Dios Guillermo, Macía Manuel J, Arellano Gabriel, Granzow-de la Cerda Íñigo, Vega-Álvarez Julia, Arnelas Itziar, Espinosa Carlos I, Salinas Norma, Cayuela Luis
Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, Calle Tulipán s/n, Móstoles, Madrid, ES-28933, Spain.
Departamento de Biología, Área de Botánica, Universidad Autónoma de Madrid, Calle Darwin 2, Madrid, ES-28049, Spain.
Plant Divers. 2024 Mar 25;46(4):491-501. doi: 10.1016/j.pld.2024.03.005. eCollection 2024 Jul.
Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short distances. Biodiversity research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients, but other facets should be considered. For first time, we simultaneously assessed elevational trends in taxonomic, functional, and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary causes. This investigation covered four transects (traversing . 2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range (. 10°). Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic, functional, and phylogenetic diversity as elevation increased, although the decrease was less pronounced for higher Hill orders. The exception was a slight increase in phylogenetic diversity when dominant species were over-weighted. The decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands, where the increasingly harsher conditions exclude species and functional strategies. Besides, the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional diversity. For phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate lineages. This could be explained by a decreasing presence and abundance of temperate, extratropical taxa towards the central Andes relative to northern or southern Andes, where they are more prevalent.
由于山脉在短距离内包含了地形和气候的镶嵌体，因此对于探索生物多样性模式至关重要。传统上，生物多样性研究在调查沿海拔梯度的变化时，主要关注分类多样性，但也应考虑其他方面。我们首次同时评估了安第斯热带山地森林木本植物在分类、功能和系统发育多样性方面的海拔趋势，并探讨了其潜在的生态和进化原因。这项调查涵盖了四个样带（跨越海拔2200米），在广泛的纬度范围内（超过10°）包括114个0.1公顷的样地。我们使用希尔数来量化37869个个体中基于丰度的多样性，发现随着海拔升高，分类、功能和系统发育多样性均持续下降，尽管对于较高的希尔阶数，下降不太明显。唯一的例外是当优势物种被加权时，系统发育多样性略有增加。分类和功能多样性的下降可能归因于对高地的环境过滤过程，那里日益恶劣的条件排除了物种和功能策略。此外，希尔阶数之间陡峭度下降的差异表明，稀有物种对功能多样性的贡献不成比例。对于系统发育多样性，希尔阶数之间海拔趋势的变化表明，相对于远缘的温带谱系，具有强烈生态位保守性的热带低地起源物种在安第斯中部高地的影响比以前认为的更大。这可以通过相对于安第斯山脉北部或南部，温带、温带以外的分类群在安第斯中部的存在和丰度下降来解释，而在安第斯山脉北部或南部它们更为普遍。
