Biodiversity redistribution under climate change Impacts on ecosystems and human well-being
BACKGROUND: The success of human societies depends intimately on the living components of natural and managed systems. Although
the geographical range limits of species are dynamic and fluctuate over time, climate change
is impelling a universal redistribution of life on
Earth. For marine, freshwater, and terrestrial
species alike, the first response to changing
climate is often a shift in location, to stay within
preferred environmental conditions. At the
cooler extremes of their distributions, species
are moving poleward, whereas range limits are
contracting at the warmer range edge, where
temperatures are no longer tolerable. On land,
species are also moving to cooler, higher elevations; in the ocean, they are moving to colder
water at greater depths. Because different species
respond at different rates and to varying degrees,
key interactions among species are often disrupted, and new interactions develop. These
idiosyncrasies can result in novel biotic communities and rapid changes in ecosystem functioning,
