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reserve networks, which maximize habitat in future climate space (Hannah et al. 2007, Willis
et al. 2010, Gillson et al. 2013).
Though practical examples are still scarce (Williams et al. 2013), long-term data are being
effectively applied in Amazonia and the tropical Andes, where palaeoecologists are working
to include their work into climate-change integrated conservation strategies (Bush 2002).
Amazonia and the tropical Andes are two of the world's hottest biodiversity hotspots. They
have exceptional species richness and high levels of threat, caused by deforestation and con-
version to agriculture (Myers et al. 2000). Reduced humidity and increased drought stress are
predicted to cause an overall decrease in forest cover, a switch to dry or deciduous forest in
the western part of the basin and a switch from evergreen rainforest to savanna in the east,
with fire encroachment amplifying forest loss (see Chapter 4) (Cowling et al. 2004, Bush et al.
2008, Rull et al. 2013). The situation is exacerbated by the possibility of decreased rainfall due
to deforestation in the eastern Amazon. As a result of these interacting factors, the Amazon
may tip from being a carbon sink to a carbon source (Huntingford et al. 2013).
A 3 °C increase in temperature and a 20% reduction in rainfall are predicted over the course
of the twenty-first century (Mayle et al. 2004, IPCC 2007), and Amazonia and the tropical
Andes have both high exposure and high sensitivity to climate change, compounded by land-
use pressures (Dawson et al. 2011, Gillson et al. 2013). Detailed pollen and palaeoclimatic
records from Amazonia and the eastern flank of the Andes show how vegetation communi-
ties have responded to past changes in temperature and rainfall. A synthesis of pollen records
documenting Pleistocene/Holocene vegetation change identified areas receiving 50-100 mm
rainfall during the driest 3 months of the year as likely to experience the greatest distribu-
tional changes in the coming decades, making them priorities for climate change-integrated
conservation strategies (Figure 5.9) (Bush 2002).
In a changing climate, reserve networks are needed that protect representative habitats in
both current and future climate space. Large, isolated reserves may be less effective for con-
servation in a changing climate than chains or clusters of reserves that cover more climate
space (Pearson and Dawson 2005). An isolated reserve in a sea of transformed landscape acts
like an island, separating populations and reducing the potential for evolutionary adaptation
that comes from gene flow. Therefore, individual reserves need to be linked together in net-
works that accommodate range shifts and facilitate dispersal (Figure 5.10). Strictly protected
core areas in a wider landscape of buffered areas and corridors that link present and future
climate space will maximize the chances of species keeping pace with climate change (see
Chapter 7). Reserves that encompass a wide range of altitudes and hydrologies and that are
well connected to other reserves by corridors of wildlife-friendly habitat are more likely to
maximize climate space and facilitate migration between present and future climate space
(Pearson and Dawson 2005, Hannah et al. 2007). Preserving large populations and a wide
geographic range helps to maximize evolutionary potential, and thus enhances the capacity
of organisms to adapt to a changing environment (Lawler 2009, Lavergne et al. 2010, Sgrò
et al. 2011).
Accommodating future shifts in range requires particular attention to ecotones because
species in these areas are likely to be at the limits of their environmental and biological
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