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The Succulent Karoo Biome stretches
from Sutherland westwards to
Nieuwoudtville and Calvinia,
over the escarpment and in
a broad band along the west
coast into Namibia in the north.
This region, and in particular
Namaqualand, which is strongly
influenced by winter rainfall
and fog, is an extraordinary
desert that harbours a range
of succulent plants beyond
compare. It boasts a bulb flora
richer than that of any other
arid region and provides a
springtime display of annual
flowers that attracts photographers.
Some 5000 plant species exist
in this special region, representing
a botanical marvel to rival
the fynbos of the well-known
Cape Floral Kingdom.
The terrain varies from coastal
sandy flats to mountain ranges
of diverse geological formations
- granite, gneiss, quartzitic
sandstone, lava, quartzite,
dolomite, conglomerate and
shale. The mild temperatures
during winter and summer remain
remarkably constant as a result
of the influence of the cold
Benguela Current of the Atlantic
Ocean. In summer temperatures
can reach in excess of 40oC.
Rain borne on cold fronts falls
during winter, and is on average
less than 400 mm a year. Fog
is common nearer the coast.
The rainfall in Namaqualand
is remarkably reliable and
this is the fundamental explanation
for its unparalleled diversity
of leaf succulents, bulbs,
high numbers of minute succulents
and the regular displays of
spring flowers.
In this dwarf succulent shrubland,
leaf succulents dominate, and
most of these species are in
the Mesembryanthemaceae (> 2000
species) and Crassulaceae families.
Most of the succulents are
small and compact, and as a
result there is much space
and habitat available in which
to develop, which is why succulent
species are so diverse in this
biome. The high floral diversity
of this intriguing region and
the fact that 50% of the species
are found nowhere else in the
world, places Namaqualand in
the unique position of being
the only desert hotspot of
biodiversity.
Annual plants, mostly of the
daisy family, are largely responsible
for the impressive fields of
colour during spring. However,
these annuals constitute only
8% of the flora of the Succulent
Karoo. The annuals are a result
of human interference with
the environment: they reclaim
the ploughed wheat fields.
In addition to the rich plant
life, this area has a diversity
of tortoises, lizards, molerats,
monkey beetles, bee flies,
bees, wasps and scorpions.
Mammals such as bat-eared fox,
aardwolf, steenbok and duiker,
and reptiles are abundant.
Brant’s whistling rat
is responsible for the burrow
systems in sandy areas, which
provide ideal conditions for
seed germination. Of importance
in the area are heuweltjies,
raised mounds of calcium-rich
soil, which support distinctive
plant communities. It is thought
that these were created by
termites.
Small stock (sheep and goats)
is ranched in the Succulent
Karoo. Mining for limestone,
gypsum, diamonds and zinc,
although contributing to the
economy, results in destruction
of the vegetation and heaps
of unvegetated spoil. Fruit
is grown along the river valleys
and Ostrich farming is practiced
in the south of the Biome.
Less than 0.5% of the area
of the Succulent Karoo Biome
is conserved. Ecotourism might
be a viable option for a conservative
means of landuse, as long as
there is careful management
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