Grasslands of the World.pdf - Disasters and Conflicts - UNEP

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Plate 11.22
The Himalaya -Hindu Kush and Tibetan Plateau area.
Grasslands of the world
the true Himalaya , through the foothills of the Karakoram to the Hindu Kush
and most of Afghanistan’s mountains, to the shoulder of the Pamirs; in the west
of Pakistan it includes the Balochistan uplands. The grazing lands of Nepal and
Bhutan are at the eastern end of the zone.
There is a wide altitudinal range, from the plains at 200–300 m, to the snow
line, which may be over 5 000 m in summer . Rainfall increases southeastwards;
the most northerly, semi -arid parts are in the rain-shadow of the Himalaya ,
but thereafter the grasslands receive the monsoon, and Nepal and Bhutan are
humid. Temperatures also rise with decreasing latitude, the pastures range from
about 37°N to 27°N. There are, therefore, considerable differences in vegetation
, in altitudinal bands and north–south changes.
The flora of the semi -arid west shows considerable Western and Central
Asia n influences – the wild olive grows as far east as western Nepal . In all cases,
the Himalayas abut the great alluvial plains, but at low altitude the vegetation
changes as well . In Pakistan , the foothills are under Acacia forest ; in the Nepal
Terai there is dipterocarp (sal – Shorea robusta ) forest, indicating higher rainfall
and a warmer climate.
Afghanistan is at the convergence of the Mediterranean, the Tibetan and the
Himalayan vegetation types , and towards the Pakistan border is influenced
by the monsoon. For the vast majority of the grazing lands , low precipitation ,
with winter incidence, means that the main grazing vegetation type is Artemisia