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Mountain environments provide a wide range of
ecosystem services, from the cycling of nutrients,
water and greenhouse gases to disease regulation and
protection from landslides and floods. The Tropical
Andes contain a wide spectrum of microclimates,
harbouring a unique diversity of ecosystems, such as
glaciers, high mountain grasslands, mountain forests,
rivers, lakes and wetlands. The ecosystems in the most
tropical parts of the Andes, the north and along the
eastern slopes, have particularly diverse and populous
wildlife. The whole region is one of the biodiversity
hotspots most vulnerable to climate change (Malcolm
et al., 2006), partly due to its low inter-annual variability,
which means that ecosystems are not adapted to long-
term climate variability (Williams and Jackson, 2007).
Therefore, many of the expected impacts of climate
change will come indirectly through affecting these
ecosystems and their services to society.
A biome-based model, using a high-emission
scenario, predicts a potential 25 per cent change
in ecosystem distribution in the Andes by 2050,
based on preferred climatic conditions (Tovar et al.,
2013). Glaciers, cloud forests and páramos are most
vulnerable to climate change (Young et al., 2011),
with the highest relative loss of area being predicted
for these ecosystems and tropical mountain forests
such as Yungas (Tovar et al., 2013). These losses
can be explained by the direct impact of climate
change on hydrology, and also by the high altitude
of these ecosystems. Their altitude implies difficulty
for species to migrate, a high rise in temperature
Loss of ecosystem functions and biodiversity
and other factors resulting in fragility. However, this
model does not take into account land-use change,
which is the most damaging stressor on regional
ecosystems (Magrin et al., 2014).
To adapt successfully to climate change, mountain
ecosystem services must be recognized and preserved.
Climate change, in combination with other stressors
such as land-use changes, invasive species, poaching and
pollution, puts significant pressure on fragile mountain
environments. Reduction of these other stressors will
increase the capacity to adapt. Human activities directly
determine the landscape in large parts of the Tropical
Andes. One study estimates that human activity – in
varying degrees – has transformed on average 22 per
cent of the area directly (Josse et al., 2009).
Vicuñas, Peru
Flora in the Altiplano, Bolivia