Geoscience Reference
In-Depth Information
Climate change, palaeoecology, and conservation planning
An integrated suite of approaches can help to bridge the gap between past, present, and
future, forming a sound basis for adaptation and conservation decision making (Dawson
et al. 2011, Gillson and Marchant 2014). There is good potential to integrate palaeoecological
and palaeoclimate data alongside modern ecological studies, monitoring, experiments and
environmental change data to improve the confidence with which climate change responses
can be predicted for individual species and for ecosystems and biomes (Dawson et al. 2011,
Gillson and Marchant 2014). As species and biome boundaries shift towards higher latitudes
and altitudes, information on past distribution changes can help in the development of pro-
tected areas networks that connect present and future climate space and inform landscape
configurations that are most likely to facilitate migration and conserve a representative range
of habitat types. This approach must expand beyond protected areas to include resilient soci-
oecological systems that have the capacity to adapt to changing environmental conditions
and social needs. The following section contains some suggestions as to how long-term per-
spectives can contribute to the development of climate change—integrated conservation
strategies.
Can species distribution keep up with climate change?
In response to changing climate, species can adjust their distribution in order to track suit-
able climate space, generally moving upslope or to higher latitudes. The velocity of climate
change is the distance per year that species need to move to keep within their current climate
envelope, and is estimated to be more than 1 km per year for most of the world, and possibly
as high as 3-5 km per year (Petit et al. 2008, Diffenbaugh and Field 2013). Understanding the
response rate of different species is essential to identifying those which are most sensitive to
climate change and those which may need assisted migration to keep pace with suitable cli-
mate space. The potential rates of migration during rapid warming can be inferred from the
fossil pollen record, and migration rates at the start of the Holocene may have been just 0.1 to
2  km per year (McLachlan et  al. 2005). However, such estimates may be overly optimistic,
because small populations of trees may have survived in warmer refuges through the last gla-
cial maximum, providing seed populations that spread during early Holocene warming;
however, these 'cryptic refugia' are too small to appear in the fossil pollen record (Provan and
Bennett 2008). To provide more accurate estimates, a combination of palaeoecological tech-
niques alongside studies of modern genetics and ancient DNA will be needed (McLachlan
et al. 2005, Pearson 2006, Petit et al. 2008).
Regardless of such refinements, it seems likely that many species will not be able to move at
climate change velocity, because of inherently poor dispersal ability, geographic barriers, and
fragmentation and transformation of landscape. Palaeoecological studies may help to iden-
tify species that will require translocation ('assisted migration') to keep up with climate space
at the high latitude/altitude, or leading, edge of their distributional range (McLachlan et  al.
2007, Hewitt et al. 2011). On the other hand, humans facilitate species spread by augmenting
 
Search WWH ::




Custom Search