Mountains are often called nature's water towers. They intercept air circulating
around the globe and force it upwards where it condenses into clouds, which provide
rain and snow.
Mountains also store water in various ways, including the
formation of snow and ice which is later released as melt-off during warmer periods
(often those with the lowest rainfall).
It is no surprise then that in
semi-arid and arid regions, over 70 to 90 percent of river flows come from mountains.
But even in temperate areas, 30 to 60 percent of freshwater can come from highland
watersheds. In the Rhine basin, for example, the Alps provide 31 percent of annual
flows in summer more than 50 percent even though they make up just
11 percent of the basin's land area.
In fact, all the major rivers in
the world from the Rio Grande to the Nile have their headwaters
in mountains and one of every two people on the planet depends on mountain water
in one way or another: for drinking, as a source of energy or income, for growing
A precious, and finite, resource
That water plays a
major role in sustaining human life is obvious. Worldwide, freshwater supplies
12 percent of the fish people eat, accounts for some 20 percent of electrical
power generation and supports about 40 percent of food-crop production via
But the power of mountain rivers isn't always exported to lower
elevations. In rural Nepal, for example, there are an estimated 25 000 water
wheels and over 900 micro-hydropower turbines a more recent technology
that provide a critical source of energy for area residents.
however, it is becoming clear that without more attention to the sustainable management
of this finite resource, emerging water supply problems will only worsen
with serious consequences for agriculture and food security, especially in the
Today, around 1.1 billion people worldwide do not benefit
from access to safe water supplies. A disproportionate number live in developing
countries where water scarcities are so great that the ability to grow food and
to build a stable economy have been severely hindered.
The trickle-down effect
to what one may think, mountains are fragile ecosystems. The vertical nature of
a mountain its contours, projections, peaks and plateaus makes its
surface unstable. Mountain soils, which form more slowly because of higher altitudes
and colder temperatures, are often young, shallow, poorly anchored and susceptible
Human activities can tip the delicate balance of mountain
ecosystems. Deforestation of high-altitude woodlands, mining, unsustainable agriculture,
urban sprawl and global warming are all taking their toll on mountain watersheds
and, through impacts that relate to water, on people and ecosystems downstream.
happens in upland watersheds has a massive impact on downstream areas," notes
an FAO fact sheet on the subject. "Often, the health of an entire watershed
depends on preventing environmental degradation in these areas."
mountain ecosystems help prevent soil erosion, reduce sedimentation in reservoirs
and mitigate the risks of mudslides and floods, all problems that can threaten
downstream water supplies.
However, mountain populations are amongst the
poorest and most disadvantaged in the developing world poverty, isolation,
population growth and limited access to land are forcing many upland peoples to
adopt farming and survival practices that damage the environment, says FAO.
challenge then is not only to protect mountain ecosystems, but to involve mountain
communities in doing so in ways that are culturally and economically appropriate
and strengthen their abilities to earn livelihoods in a sustainable fashion.
As part of its work to strengthen land and water resource
management in highland areas, in 2002 FAO launched the initiative, The Next
Generation of Watershed Management Programmes.
in close collaboration with partners, recently conducted an extensive review of
the successes and shortcomings of watershed-based management in forests and mountain
areas and will soon issue a set of guidelines for good watershed management as
a tool for policy-makers, communities, government agencies and others involved
with managing mountain resources.
FAO also chose "Mountains: source
of freshwater" as the theme the first-ever International Mountain Day to
build awareness of the key role that mountains play in supplying the world with
Water is essential to human life, and healthy mountain ecosystems
are essential to global water supplies," says Douglas McGuire, head of FAO's
Mountain Group. "By taking care of the world's mountains, we help to ensure
the long-term survival of all that is connected to them, including ourselves."
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