Data from: Phylogenetic diversity reveals hidden patterns related to population source and species pools during restoration

1. A phylogenetic perspective of community assembly can reveal new insights into how variations within dominant species interact with the local species pool to influence the structure of restored plant communities. Many studies have examined the effect of dominant species in structuring plant communities, but few have investigated their effect on phylogenetic diversity (PD). 2. We established grassland in a post-agricultural field using two population sources (cultivars and local ecotypes) of three dominant grasses (Sorghastrum nutans, Andropogon gerardii, and Schizachyrium scoparium) with three unique pools of subordinate species that varied in PD but not taxonomic or life-form diversity. We tested the effect of the population source treatment on two metrics of community PD (Net Relatedness Index [NRI] and Nearest Taxon Index [NTI]) during the first four years of restoration. The NRI measures the overall pairwise phylogenetic distance between all pairs of taxa in a community. By contrast, NTI measures the pairwise distance between closely related taxa in a community. 3. Population sources had a transitory effect on community phylogenetic structure over time. Local ecotypes decreased the abundance of closely related eudicots, monocots (low +NRI and +NTI values) and volunteer species (-NTI) more than cultivars. However, population sources did not affect ecologically conservative species (i.e. species with intermediate to poor ecological tolerance and a high degree of fidelity to prairie habitats). Thus, cultivars might have a positive effect on community phylogenetic diversity more than local ecotypes by decreasing the abundance of a phylogenetically diverse community of less closely related volunteer species. Differences in PD of seed mixes were maintained in the community of high fidelity species, but did not affect PD of the unsown (volunteer) species in the assembling community. 4. Synthesis and applications. This is the first experiment to show consequences of using different seed sources on phylogenetic diversity (PD) in grassland restoration. Phylogenetics can reveal effects of population sources on the abundance of volunteer species not evident through traditional analyses of species diversity. The PD of seed mixes or establishing communities, or other assessments of phylogenetic relationships, by restoration practitioners is recommended as a metric to allow consequences of the evolutionary patterns among species to be included in conservation planning. Increased accessibility of phylogenetic tools will allow the application of PD in restoration monitoring.

1. 群落构建的系统发育视角能够为揭示优势种内变异与本地物种种库的相互作用如何影响恢复植物群落结构提供新认知。已有诸多研究探讨了优势种在构建植物群落中的作用，但鲜有研究考察其对系统发育多样性（phylogenetic diversity, PD）的影响。
2. 我们在一处农田弃耕地中构建草原群落，实验材料包含3种优势禾草——须芒草（Sorghastrum nutans）、大须芒草（Andropogon gerardii）与小须芒草（Schizachyrium scoparium）——的两种种群来源：栽培品种（cultivars）与本地生态型（local ecotypes），并搭配3组系统发育多样性存在差异，但分类学多样性与生活型多样性无显著区别的从属物种种库。在群落恢复的前四年间，我们测试了种群来源处理对两种群落系统发育多样性指标——净亲缘关系指数（Net Relatedness Index, NRI）与最近类群指数（Nearest Taxon Index, NTI）——的影响。其中，NRI衡量群落内所有类群两两之间的整体系统发育距离；与之相对，NTI衡量群落内亲缘关系密切的类群之间的两两距离。
3. 随时间推移，种群来源对群落系统发育结构的影响具有暂时性。相较于栽培品种，本地生态型更显著地降低了亲缘关系密切的真双子叶植物、单子叶植物（表现为+NRI与+NTI值）以及自生种的丰度（表现为-NTI值）。不过，种群来源并未对生态保守性物种产生影响——此类物种指生态耐受度中等至较差、且对高草草原生境具有高度专一性的物种。由此可见，栽培品种或许比本地生态型更能提升群落系统发育多样性，其作用途径是降低系统发育多样且亲缘关系较远的自生种的丰度。播种混合物的系统发育多样性差异在高专一性物种种群中得以保留，但并未对构建群落中非播种自生种的系统发育多样性产生影响。
4. 总结与应用。本研究为首个验证草原恢复工程中使用不同种子来源对系统发育多样性（PD）产生影响的实验。系统发育分析能够揭示种群来源对自生种丰度的影响，而这一效应无法通过传统的物种多样性分析被观测到。我们建议恢复实践者将播种混合物或定植群落的系统发育多样性，或是其他系统发育关系评估指标，纳入保护规划范畴，以充分考量物种种间进化模式所带来的影响。随着系统发育分析工具的易用性不断提升，系统发育多样性将有望被应用于恢复监测工作中。