Rapid reorganization of global biodiversity

Twenty-five years of research on the relationship between biodiversity and ecosystem function have revealed that biodiversity drives fundamental ecosystem processes and regulates their temporal and spatial stability (1, 2). Despite clear signs that human efforts have failed to halt global biodiversity loss (3, 4), it has been difficult to identify corresponding signs of global-loss trends in the context of local ecosystems (5–9). On page 339 of this issue, Blowes et al. (10) report their analysis of local biodiversity changes using a large dataset of >50,000 biodiversity time series from 239 studies. Each time series represents a record of species composition at a selected site over time, with sites representing all major ecosystem types and climatic zones. The authors demonstrate that the identities of species and their abundances are being rapidly reorganized).

Britas Klemens Eriksson1, Helmut Hillebrand

18 oct, 2019

The geography of biodiversity change in marine and terrestrial assemblages

Human activities are fundamentally altering biodiversity. Projections of declines at the global scale are contrasted by highly variable trends at local scales, suggesting that biodiversity change may be spatially structured. Here, we examined spatial variation in species richness and composition change using more than 50,000 biodiversity time series from 239 studies and found clear geographic variation in biodiversity change. Rapid compositional change is prevalent, with marine biomes exceeding and terrestrial biomes trailing the overall trend. Assemblage richness is not changing on average, although locations exhibiting increasing and decreasing trends of up to about 20% per year were found in some marine studies. At local scales, widespread compositional reorganization is most often decoupled from richness change, and biodiversity change is strongest and most variable in the oceans.

By Shane A. Blowes, et al.

Oct 18th, 2019