Drivers of global pre-industrial patterns of species turnover in planktonic foraminifera

Anthropogenic climate change is altering global biogeographical patterns. However, it remains difficult to quantify how bioregions are changing because pre-industrial records of species distributions are rare. Marine microfossils, such as planktonic foraminifera, are preserved in seafloor sediments and allow the quantification of bioregions in the past. Using a recently compiled data set of pre-industrial species composition of planktonic foraminifera in 3802 worldwide seafloor sediments, we employed multivariate and statistical model-based approaches to study spatial turnover in order to 1) quantify planktonic foraminifera bioregions and 2) understand the environmental drivers of species turnover. Four latitudinally banded bioregions emerge from the global assemblage data. The polar and temperate bioregions are bi-hemispheric, supporting the idea that planktonic foraminifera species are not limited by dispersal. The equatorial bioregion shows complex longitudinal patterns and overlaps ...

人为气候变化正在改变全球生物地理格局。然而，当前仍难以量化生物区域的变化趋势，原因在于物种分布的前工业时代记录极为稀缺。海洋微化石（如浮游有孔虫（planktonic foraminifera））保存在海底沉积物中，为量化历史时期的生物区域提供了可行途径。本研究依托最新整合的全球3802个海底沉积物站位的浮游有孔虫前工业时代物种组成数据集，采用多变量分析与基于统计模型的研究方法开展空间物种更替研究，旨在实现两大目标：1）量化浮游有孔虫的生物区域划分；2）解析物种空间更替的环境驱动因子。全球群落组合数据共识别出4个沿纬度带状分布的生物区域：极地与温带生物区域呈跨半球分布，这一结果佐证了浮游有孔虫物种不受扩散限制的假说；赤道生物区域则呈现复杂的经度分布格局，并存在重叠……