Global Change and Mountains: Consequences, Responses and Opportunities - Impact of Global Changes on Mountains: Responses and Adaptation - page 106

indiscriminate deforestation (200000 ha/year) has been bringing about
major land-use changes for the last two centuries. This has adversely affected
the hydrological cycle of watersheds resulting in the destruction of fi sh and
wildlife habitats, accelerated soil-erosion and landslides, pollution of water
sources and loss of biodiversity and wilderness, in the entire province.
As a result, the forest resources have depleted and eroded steadily and
signifi cantly bringing about rapid changes in the natural environment and
biodiversity of the region.
In the Andes Mountains large scale conversion of forests into pastures
and cultivated land has been taking place for the last century. The pressures
on natural resources in the Andes result from expanding populations,
expanding agricultural areas and intensity, and increasing mineral
extraction (Romero et al. 2009). Studies indicated that intensive grazing
is disrupting the Andean hydrological cycle by reducing interception and
transpiration and increasing runoff (CONDESAN 2011). In Chilean Andes,
hundreds of thousands of hectares of rainforest and shrubs were burned
at the beginning of the 20th century in an attempt to introduce livestock
and agriculture in unsuitable lands, resulting in degradation of natural
ecosystem through accelerated soil erosion, rapid loss of biodiversity
and depletion of water resources (Romero et al. 2009). These changes also
resulted in c onfl icts between public and private use of resources all over
Chile after 30 years of extreme application of liberal economic and political
ideas (Romero et al. 2009). Current changes in land use are responsible for
growing pressures on natural ecosystems in the Andes. This is substantiated
by the fact that at the regional level South America suffered the largest net
loss of forest between 1990 and 2010, at about 0.6 hectares per year above
Africa for the period 2000-2010 (FAO 2010). Between 1990 and 2010, forest
extent for the whole of the seven Andean countries decreased by 239,110 km 2
registering a decrease of 35 to 38% of country area covered in forest (FAO
2010). In the northern Andes excluding Chile and Argentina, transformed
ecosystems were found to the extent of 22% of the area for the period
2000-2003 which varies from 3% of transformed areas in Bolivia to as much
as 58% in Colombia. The transformed natural landscape is actually much
larger in the northern part of the continent in comparison to the Central
Andes (Romero et al. 2009). In the European Alps, mountain agriculture is
becoming less and less competitive given the diffi cult conditions of climate
and terrain (Borsdorf et al. 2008).
Urban Growth in High Mountains
Urban development has emerged as one of the most important global
change drivers infl uencing the mountain regions not only in North America
and Europe but also in developing countries in Asia, Africa and Latin