Outlook on climate change adaptation in the Tropical Andes mountains

Loss of ecosystem functions and biodiversity

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

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).

Flora in the Altiplano, Bolivia

Vicuñas, Peru

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