Impacts of climate change on water resources in Central Asia
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Número 25, 2009
vides employment for much of the rural population. The lives of some
22 million people in Central Asia directly or indirectly depend on ir-
rigated agriculture. The vulnerability of agriculture is also caused by an
increase in natural hydrometeorological phenomena, the loss of water
supply and the expansion of areas of soil degradation.
The negative consequences of climate change for hydro-power at the giv-
en stage are caused more by landslide and mud-flow phenomena than by
a change in the hydrological regime of the rivers. So, the infrastructure for
constructing Rogun HPP in Tajikistan was a victim of the flood in 1993.
In the same river basin, in March 2002, owing to a complex influence of
geodynamic and meteorological factors (storm precipitation), a large land-
slide massif was formed in the tail-water of Baipaza HPP. The increase in
precipitation, especially in the areas subject to water erosion, has intensified
the increase in silting of reservoirs. The formation and break-up of glacial
lakes also constitute a potential threat to hydro-power infrastructures in this
area. The reduced river flow that is expected over the mid- and long-term
future will be unfavourable for hydro-power; it will also require reconstruc-
tion and change of the operating regime mode of waterworks facilities, the
construction of additional reservoirs, protection facilities etc.
The influence of climate change is more obvious on the environment.
More long, dry periods together with high spring and summer air tempera-
tures can potentially increase the risk of processes of soil degradation and
desertification. The anthropogenous influence
occurring within climatic
changes will aggravate these processes even more. In this region, more than
5 million hectares of irrigated land is in an unsatisfactory state as regards
soil-reclamation, and is subject to salinization and waterlogging. There is
uncontrolled felling of trees and shrubs in a zone of flow formation that
is linked with hydro-power deficit in winter periods. The structure and
efficiency of ecological systems are also subject to risk by the influence of
global climate change. It is expected that in connection with reductions in
river flow and temperature rise, together with an increasing anthropogenous
load, the riparian woodlands will be degraded. In the case of frequent, pro-
Sulton Rahimov
50
Documentos CIDOB, Asia
Impacts of climate change on water resources in Central Asia
longed drought, hygrophilous vegetation may be under threat. Warming
will result not only in a change in diversity of flora and fauna species, but
also in changes of biological interrelations in ecosystems. Against this back-
ground, new kinds of flora and fauna may also occur, species that are not
characteristic to the region. Expected climate change may have a negative
influence on the state of natural pastures and hayfields, which are a source of
production of cheap food for animal husbandry.
Different disasters such as droughts, floods, mudflows, landslips, etc are
increasing in the region owing to the climate changes that are occurring.
Annual economic losses from such phenomena total hundreds of millions of
dollars, not counting human lives. According to the Human Development
Report on Central Asia (2005) the potential economic costs may reach 70%
of the GDP of Tajikistan, 20% of Kyrgyzstan’s, with more moderate figures
of 3-5% in Kazakhstan, Turkmenistan and Uzbekistan.
Owing to climate change occurring in the region, phenomena have
been observed such as an increase in cardiovascular
system pathologies,
a growing influence of hypoxia in high-mountain areas, and outbreaks
of epidemics of infectious-parasitic diseases connected with tempera-
ture rise and air humidity. In the case of floods,
storm precipitation
and the deterioration of the state of public water supply systems, to-
gether with abackground of high temperatures, the risk of typhoid fever,
paratyphois, salmonellosis, dysentery, amebiasis, helminthiasis, etc. has
increased (Kajumov; Makhmadaliev, 2002).
The above problems require urgent measures
to be taken to adapt
to climatic changes and to mitigate their influence in all Central Asia
countries.
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