Introduction and Road Map for Impact of Global Changes on High-Mountains - Impact of Global Changes on Mountains: Responses and Adaptation - page 25

springs and decreasing trends of stream water discharge) reducing irrigation
facilities and decreasing the irrigated land by 2% each year from 1985 till
2012, whereas the monsoon hydrological hazards (i.e., fl ash fl ood, river-
line fl ood, soil erosion and water induce landslide, etc.) degraded the 22%
agricultural land each year through extreme hydro-meteorological events.
Consequently defi cit agricultural crop yields have led to food defi ciency
and the people are now adopting other occupations which ultimately is
changing the existing rural livelihood pattern.
Sati explores the impact of global changes in Kewer Gahera sub-
watershed in India. Just like in any other region, high population growth
rate has also been observed in the Kewer Gadhera sub-watershed, increase
in forestland and decrease in agricultural land was also observed during
the last four decades. The author in this chapter has examined land-use/
cover changes during the last four decades in the Kewer Gadhera. Sati has
also described how large scale emigration and land abandonment have led
to the land-use/cover changes in the region.
In the last case study about the HKH Tibetan plateau glaciers Hasnain
takes a slightly different angle and has explored the geopolitics in the
region and how international cooperation can be used to deal with impact
of climate change on glaciers. From all the case studies discussing the HKH
and Himalayan rivers, it is apparent that climate change is impacting the
region and water source on which billions of people depend for water and
their livelihoods. It has also become clear that it is a trans-boundary issue
and keeping the sensitivity of relations between neighboring countries it is
imperative that some kind of cooperation mechanism is developed to deal
with the problems arising due to global changes in the region.
Globally, the glaciers are in a general state of retreat, most probably
because of climatic warming. They often leave behind voids fi lled by
melt water called glacial lakes which tend to burst because of internal
instabilities in the natural moraine dams retaining the lakes (e.g., as a result
of hydrostatic pressure, erosion from overtopping or internal structural
failure) or as a result of an external trigger such as a rock or ice avalanche
or even earthquake. In the last chapter with examples from the Himalayan
region, Manfred et al. have taken the case study of GLOFs to describe the
impact of climate change on high mountains (especially as they relate to
melting glaciers). This is an important issue because of the damage it can
cause to the settlements around the area.
Just like the HKH are important for water supply for millions of people,
Sri Lanka's Central Highlands occupy a unique position among the main
geographical zones of the country and has a diverse blend of most of the
world's climatic features. The Central Highland area is also the watershed
for 103 main rivers and more than 1,000 feeder streams joining the main
rivers. This area is the heart of the entire country because of its important