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Fynbos Biome is
considered by many to be synonymous with the Cape
Floristic Region or Cape Floral Kingdom. However,
the "biome" refers only to the two key vegetation
groups (Fynbos and Renosterveld) within the region,
whereas both the "region" and the "kingdom" refer to
the general geographical area and include other
vegetation types in the Forest, Nama Karoo,
Succulent Karoo and Thicket Biomes, but exclude
peripheral outliers of the Fynbos Biome such as the
Kamiesberg, North-western and Escarpment Mountain
Renosterveld and Grassy Fynbos east of
Port
Elizabeth. However, the contribution of Fynbos
vegetation to the species richness, endemicity and
fame of the region is so overwhelming, that the Cape
Floristic Region and Cape Floral Kingdom can be
considered to be "essentially Fynbos."
The Cape Floral Kingdom is the smallest of the
six Floral Kingdoms in the world, and is the only
one contained in its entirety within a single
country. It is characterized by its high richness in
plant species (8,700 species) and its high
endemicity (68% of plant species are confined to the
Cape Floral Kingdom). The Cape Floral Kingdom thus
compares with some of the richest floras worldwide,
surpassing many tropical forest regions in its
floral diversity.
In South Africa, over one third of all plant
species occur in the Cape Floral Kingdom, even
though the Kingdom occupies less than 6% of the area
of the country. This is not primarily due to the
large number of vegetation types in the Cape Floral
Kingdom. Over 7,000 of the plant species occur in
only five Fynbos vegetation types, with perhaps an
additional 1,000 species in the three Renosterveld
vegetation types.
The contribution of Succulent and Nama Karoo,
Thicket and Forest vegetation types in the region to
the plant species diversity is thus relatively
small. Thus, although the Cape Floral Kingdom
contains five biomes, only the Fynbos Biome,
comprising the Fynbos and Renosterveld vegetation
groups, contains most of the floral diversity.
Furthermore, the Cape Floral Kingdom traditionally
does not include the Fynbos and Renosterveld
vegetation outliers to the north and east. Including
these would mean that endemicity would approach 80%,
the highest level of endemicity on any subcontinent.
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Distressingly, some three-quarters of
all plants in the South African Red Data
Book occur in the Cape Floral Kingdom: 1 700
plant species are threatened to some extent
with extinction! This is much more than one
would expect based on either the area of the
Kingdom (6%) or its plant numbers (36%).
This again reflects the unique nature of
Fynbos vegetation: many Fynbos species are
extremely localized in their distribution,
with sets of such localized species
organised into "centres of endemism."
 The city of Cape Town sits squarely on
two such centres of endemism and several
hundred species are threatened by urban
expansion. However, a more serious threat is
alien plants, which infest large tracts of
otherwise undisturbed mountains and flats:
their impact on these extremely localized
species is severe. Aliens are thus the major
threat to Fynbos vegetation and its plant
diversity, especially in the mountains. On
the lowlands and on the less steep slopes
the major threat is agriculture - new
technologies, fertilisers and crops are
steadily eating into our floral reserves.
Another important threat is the misuse
of fire. Fynbos must bum, but fires in the
wrong season (such as in spring, instead of
late summer) or too frequently (so that
plants do not have time to set seed)
eliminate species. Several factors influence
fire dynamics in Fynbos global warming,
grazing practices and fire management
(ignition events, size of burns), but their
relative importance and interactions are
poorly understood.
The two major vegetation groupings in
Fynbos are quite distinct and have
contrasting ecological systems. Essentially,
Renosterveld used to contain the large
animals in the Cape Floristic Kingdom, but
these are now extinct or else have been
reintroduced into conservation areas. By
contrast, Fynbos is much richer in plant
species, but has such poor soils that it
cannot support even low densities of big
game. However, most of the endemic
amphibian, bird and mammal species in the
region, occur in Fynbos vegetation types
(Source: "The Vegetation of South
Africa, Lesotho and Swaziland", South Africa
Department of Environmental Affairs and
Tourism)
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