Data from: Species richness change across spatial scales

AbstractHumans have elevated global extinction rates and thus lowered global-scale species richness. However, there is no a priori reason to expect that losses of global species richness should always, or even often, trickle down to losses of species richness at regional and local scales, even though this relationship is often assumed. Here, we show that scale can modulate our estimates of species richness change through time in the face of anthropogenic pressures, but not in a unidirectional way. Instead, the magnitude of species richness change through time can increase, decrease, reverse, or be unimodal across spatial scales. Using several case studies, we show different forms of scale-dependent richness change through time in the face of anthropogenic pressures. For example, Central American corals show a homogenization pattern, where small scale richness is largely unchanged through time, while larger scale richness change is highly negative. Alternatively, birds in North America showed a differentiation effect, where species richness was again largely unchanged through time at small scales, but was more positive at larger scales. Finally, we collated data from a heterogeneous set of studies of different taxa measured through time from sites ranging from small plots to entire continents, and found highly variable patterns that nevertheless imply complex scale-dependence in several taxa. In summary, understanding how biodiversity is changing in the Anthropocene requires an explicit recognition of the influence of spatial scale, and we conclude with some recommendations for how to better incorporate scale into our estimates of change., Usage notesdata_for_dryadThis file contains all data associated with the manuscript. A metadata file is included in the zip folder.摘要：人类活动推高了全球灭绝速率，进而降低了全球尺度的物种丰富度。然而，尽管该关联常被默认成立，但并无先验依据表明全球物种丰富度的丧失总会、甚至经常会逐级传递至区域与局地尺度的物种丰富度损失。本研究表明，面对人为压力时，空间尺度可调控我们对物种丰富度随时间变化的估算结果，且这种调控并非单向的。反之，物种丰富度随时间的变化幅度在不同空间尺度下可呈现升高、降低、逆转甚至单峰模式。通过多个案例研究，我们展示了人为压力下物种丰富度随时间变化的尺度依赖模式：例如，中美洲珊瑚群落呈现同质化特征，小尺度下物种丰富度基本未随时间发生变化，而大尺度下的物种丰富度变化则呈显著负值；与之相对，北美鸟类群落则表现出分化效应，小尺度下物种丰富度同样基本维持稳定，但大尺度下的变化则更为正向。最后，我们整合了来自不同类群、覆盖从小型样地到整个大陆的长期监测研究的异质性数据，尽管模式存在高度变异性，但多个类群均表现出复杂的尺度依赖性。综上，要理解人类世的生物多样性变化趋势，必须明确认知空间尺度的影响。本文最后提出若干建议，以更好地将尺度因素纳入物种丰富度变化的估算工作中。 使用说明：data_for_dryad：本文件包含该论文关联的全部数据，压缩包内附带元数据文件。