Helmholtz Institute for Functional Marine Biodiversity (HIFMB), Ammerländer Heerstr. 231, 26129, Oldenburg, Germany.
Department of Ecology, Evolution, and Behavior, University of Minnesota, 1479 Gortner Ave, St Paul, MN, 55108, USA.
Ecol Lett. 2018 Sep;21(9):1364-1371. doi: 10.1111/ele.13102. Epub 2018 Jun 27.
Environmental change can result in substantial shifts in community composition. The associated immigration and extinction events are likely constrained by the spatial distribution of species. Still, studies on environmental change typically quantify biotic responses at single spatial (time series within a single plot) or temporal (spatial beta diversity at single time points) scales, ignoring their potential interdependence. Here, we use data from a global network of grassland experiments to determine how turnover responses to two major forms of environmental change - fertilisation and herbivore loss - are affected by species pool size and spatial compositional heterogeneity. Fertilisation led to higher rates of local extinction, whereas turnover in herbivore exclusion plots was driven by species replacement. Overall, sites with more spatially heterogeneous composition showed significantly higher rates of annual turnover, independent of species pool size and treatment. Taking into account spatial biodiversity aspects will therefore improve our understanding of consequences of global and anthropogenic change on community dynamics.
环境变化会导致群落组成发生重大变化。相关的物种迁入和灭绝事件可能受到物种空间分布的限制。尽管如此，关于环境变化的研究通常在单一空间（单个样地内的时间序列）或单一时间点的时空β多样性（spatial beta diversity at single time points）尺度上量化生物响应，而忽略了它们潜在的相互依存关系。在这里，我们利用来自全球草原实验网络的数据，来确定物种库大小和空间组成异质性如何影响两种主要形式的环境变化（施肥和食草动物减少）对周转率的响应。施肥导致更高的本地灭绝率，而在食草动物排除样地中，周转率则是由物种更替驱动的。总的来说，与物种库大小和处理无关，空间组成异质性更高的样地表现出更高的年周转率。因此，考虑到空间生物多样性方面，将有助于我们更好地理解全球和人为变化对群落动态的影响。
