Projected climatic changes lead to biome changes in areas of previously constant biome

Aim: Recent studies in southern Africa identified past biome
stability as an important predictor of biodiversity. We aimed to assess
the extent to which past biome stability predicts present global
biodiversity patterns, and the extent to which projected climatic changes
may lead to eventual biome changes in areas with constant past biome.
Location: Global. Taxon: Spermatophyta; terrestrial vertebrates.
Methods: Biome constancy was assessed and mapped using results
from 89 dynamic global vegetation model simulations, driven by outputs of
palaeoclimate experiments spanning the past 140 ka. We tested the
hypothesis that terrestrial vertebrate diversity is predicted by biome
constancy. We also simulated potential future vegetation, and hence
potential future biome patterns, and quantified and mapped the extent of
projected eventual future biome change in areas of past constant biome.
Results: Approximately 11% of global ice-free land had a constant
biome since 140 ka. Aside from areas of constant Desert, many areas with
constant biome support high species diversity. All terrestrial vertebrate
groups show a strong positive relationship between biome constancy and
vertebrate diversity in areas of greater diversity, but no relationship in
less diverse areas. Climatic change projected by 2100 commits 46–66% of
global ice-free land, and 34–52% of areas of past constant biome
(excluding areas of constant Desert) to eventual biome change. Main
conclusions: Past biome stability strongly predicts vertebrate
diversity in areas of higher diversity. Future climatic changes will lead
to biome changes in many areas of past constant biome, with profound
implications for biodiversity conservation. Some projected biome changes
will result in substantial reductions in biospheric carbon sequestration
and other ecosystem services.