Geoscience Reference
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Class-6 mountains should have altitude above 4500 m. It is interesting to
observe that this classifi cation of mountain does not consider regions below
the altitude of 2500 m, high plateaus and large intermountain valleys as
mountain areas, despite their showing several features of mountain ecology
and being interconnected with mountain ecosystems. However, areas
located just at an altitude of 300 m above mean sea level but marked with
more than 2ยบ of slope have been classifi ed as mountain areas from Class-1
to Class-3 Mountains (Table 4.1).
As per the UNEP-WCMC classifi cation of the world's mountains,
nearly 29 million km 2 area which accounts for about 22% of the total
geographical land surface of the world is under different types of mountains.
The maximum proportion of World Mountains (22 million km 2 ) is located
in developing countries and only a small proportion (5 million km 2 ) is
situated in transition countries (Table 4.1). Asia and the Pacifi c region of
the developing world shares 28%, developed countries 23% and countries
in transition have 18% of the world's mountains. The sub-regions of
developing and transition countries in which the mountain regions are
extend over more than 1 million km 2 include East Asia, the Commonwealth
of Independent States (CIS), South America, the Near East, Southeast Asia
and Oceania, South Asia and East Africa, and mountains in these sub-
regions account for approximately 90% of the total mountain areas of the
developing and transition countries (Table 4.1). However, Huddleston et al.
(2003) have classifi ed those countries as mountainous where one-third of
their population was living in mountain areas and/or in which mountainous
terrain encompass more than one-third of the total geographical area.
However, taking into the proportion of total geographical area the sub-
regions in developing and transition countries, East Asia, North America
(Mexico), Central America, Southeast Asia and Oceania and the Near East
respectively account for 50%, 45%, 41%, 35% and 34% areas of the respective
sub-region. Interestingly, 80% of the world's mountains have an altitude
2500 m and almost 50% mountains regions have an elevation below 1000
m. The high mountains in the planet extend across the Himalaya, Andes
mountain ranges and in the Tibetan plateau. Geologically, the Himalaya,
Andes, Alps and Rockies are considered as the youngest and tectonically
active mountain ranges of the world, and owing to their high elevation,
steep slope and geo-tectonic instability these mountains are characterized
with high environmental fragility as well as socio-economic vulnerability.
Nearly 90% of the mountain population live in developing or transition
countries (Huddleston et al. 2003); 50% in the Asia-Pacific region and one-
third live in China. About 30% of total world's mountain population lives
in urban centres even though during the recent years the mountain regions
of heavily populated developing countries have been experiencing rapid
urban growth (Hassan et al. 2005). Out of the total population living in the
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