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The Nama Karoo is a large landlocked
region making up 25% of the
land surface of South Africa.
Climatically and biologically
the Nama Karoo is a heterogenous
and ecotonal region. Topography
varies from expansive rocky
or sandy plains to escarpments
and flat-topped mesas. Altitude
ranges from 800 m to 2000 m.
The region is generally exposed
and windy, hot in the summer
and cold in the winter. Temperature
extremes range from -5°C
in winter to 43°C in summer.
Sutherland is the coldest place
in South Africa and receives
snow in most winters. Rainfall
varies greatly, and ranges
from 200 mm in the southwest
to 400 mm in the northeast.
The soils are as variable as
the climate. They range from
Aeolian sands to saline clays,
but are generally shallow and
fairly fertile, and overlying
either mudstones or intrusive
igneous formations.
A wide variety of life-forms
co-exist in the Nama Karoo.
Small trees occur along drainage
lines and on rocky hillsides.
Plains are dominated by low
shrubs (generally less than
1 m in height) intermixed with
grasses, succulents, geophytes
and annual forbs. The grassiness
of the vegetation varies over
time, increasing in periods
of above average summer rainfall
and decreasing in periods when
summers are drier than winters.
The Karoo region, because of
its aridity and low shrubby
vegetation, never supported
the diverse array of herbivorous
large mammals found in the
African savannas. Plant eating
animals of the Karoo are either
small and confined to protected
habitats, or are very mobile.
Springbok are common, and smaller
herbivorous mammals include
hares, rabbits, the rock hyrax,
and Otomyid rodents. Termites
are responsible for much of
the nutrient cycling in the
Nama Karoo and are also the
staple food of many other species.
Specialized insectivorous mammals
include aardwolf, aardvark,
bat-eared fox, and a variety
of long-nosed elephant shrews.
Birds include some of the smallest
and largest species in South
Africa, and the reptile fauna
is rich, including snakes,
geckos, lizards and tortoises.
There is a high diversity of
invertebrates. The brown locust
and karoo caterpillar erupt
under favourable, local rainfall
events.
Small stock is ranched throughout
the Karoo region. Ranches are
generally large (4000-15000
ha) because it takes 2-7 ha
of natural veld to support
one small-stock unit in this
region. There is a mining industry
in the north west of the region
and growing of citrus, olives,
deciduous fruit and wine grapes
in the major river valleys.
Threats to the fauna include
overgrazing (desertification)
and land transformation by
mining, agriculture and development.
Less than 1% of the biome is
conserved in formal areas.
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