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

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Grasslands of the world
the northern tip of the Monte province, Prosopis spp. are dominant in the shrub
layer, while the southern extreme is dominated by Larrea spp. The grass layer,
which is the most important forage source, is composed of a mixture of C4 and
C3 species. Towards the north, the C4 group (Panicum urvilleanum , Chloris
castilloniana , Pappophorum caespitosum and P. phillippianum ) dominate and
to the south the C3 (Stipa tenuis , S. speciosa , Poa ligularis and P. lanuginosa )
increase in importance. Prosopis spp. are widely browsed by small ruminants
like goats , as their shoots and pods are rich in protein.
ASIA
Central Asia
Pasture descriptions are included for Kyrgyzstan (Fitzherbert 2000) and
Uzbekistan (Makhmudovich, 2001). Uzbekistan’s grazing lands are described
in detail by Gintzburger et al. (2003) and the problems of transition of all
Central Asia to decollectivized farming and animal husbandry is discussed
by Ryan, Vlek and Paroda (2004) and Gintzburger (2004). The Central
Asian Region, which comprises Kazakhstan , Kyrgyzstan, Turkmenistan and
Uzbekistan, is a vast low-altitude plain, bordered to the south by mountains
that rise to the Pamirs. The Chinese Autonomous Region of Xinjiang and
the northern fringe of Afghanistan are, geographically, part of the region, but
their recent history and grassland management have been very different from
those of countries of the former USSR. These arid to semi -arid plains had,
until the twentieth century, been mainly exploited by mobile herding , with
farming concentrated in oases and the valleys of the great rivers flowing to
the Aral Sea.
The plains are below 500 m, with large areas below 200 m, sloping to the
Aral sea, which is about 53 m above mean sea level. The Uzbekistan vegetation
zones will serve to show the general banding of pastures from the grazing point
of view. The territory of the republic is divided into:
A desert belt (chul), which is the zone of irrigated farming and Karakul
sheep : annual precipitation is 100–250 mm; average annual temperature is
about 15°C. Vegetation types are desert, psammophytic shrub and ephemeralsemi
-shrub vegetation .
The foothill plains belt (adyr) is the zone of rainfed lands, with very low
precipitation . The main rainfed areas and big oases of irrigated farming are concentrated
in the desert (chul) zone. The yearly average temperature is 13°C, but
in the south it is 14–16°C; annual precipitation is 200–545 mm; the prevailing
soil type is light and typical sierozems, with widely spread ephemeral vegetation
. The mid-mountain belt (tau) is rainfed land with normal precipitation of
the Tashkent, Samarkand and Surkhandarya Regions. The average annual temperature
is 8–11°C; annual precipitation is over 400 mm. Along with rainfed
grain farming, the belt is extremely favourable for orchards and vineyards. The
high-mountains belt (yaylau) is the zone of summer pastures.