Invasion timing affects multiple scales, metrics, and facets of biodiversity outcomes in ecological restoration experiments

作者：Emma Ladouceur, Michael Wohlwend, Michele R. Schutzenhofer, Jonathan M. Chase, Tiffany M. Knight · 发表于：Ecological Applications · 年份：2025 · DOI：10.1002/eap.70062 · 被引用次数：2 · 研究领域：Ecology and Vegetation Dynamics Studies、Peatlands and Wetlands Ecology、Rangeland and Wildlife Management

The need to develop optimal restoration protocols for degraded grasslands has led to experimental research aimed at determining how different restoration treatments influence outcomes for biodiversity. The magnitude and direction of diversity responses to restoration treatments may depend on the spatial scale at which diversity is measured (local, regional), the metric of diversity used (Hill numbers), and the facet of diversity (taxonomic, functional, phylogenetic) considered. We conducted a long-term factorial experiment in a degraded grassland in Missouri, USA, in which we experimentally applied a regionally appropriate biodiverse seed mixture, added soil nutrients to restore soil fertility, and varied the timing in which the invasive plant Lespedeza cuneata entered the community. We used a unified framework of Hill numbers to evaluate how treatments influenced diversity, considering different spatial scales, metrics, and facets (taxonomic, phylogenetic, functional). We find that the timing in which the invasive L. cuneata entered the community had large effects on diversity, while nutrient addition had more limited effects. This was driven by the high dominance of the focal invasive when allowed to invade early in the growing season, suppressing diversity. The positive effects of late invasion increased in magnitude with spatial grain and were higher for taxonomic than phylogenetic and functional facets of diversity. This was largely due to the dominance of the focal inva...