Mpumalanga Biodiversity Conservation Plan Handbook - bgis-sanbi

MPUMALANGA BIODIVERSITY CONSERVATION PLAN HANDBOOK
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Painted reed frog
Hyperolius viridiflavus
Amphibians––frogs and
toads––comprise about
130 species in South
Africa. Many of them
play a crucial role in the
control of a variety of
insects including
mosquitoes.
In recent years numbers
of amphibians are
believed to have
decreased drastically.
The reason for the
decline is uncertain but it
is believed to be largely a
result of climate change
and increased
exposure to ultra violet
radiation.
3.2 VEGETATION TYPES
Vegetation types provide a good representation of terrestrial biodiversity because most
animals, birds, insects and other organisms are associated with particular vegetation types
(Rouget et al. 2004). In 2005 SANBI produced an extensively revised vegetation map for
South Africa, Lesotho and Swaziland (Mucina et al. 2005), with 441 vegetation types. Each
vegetation type in the South African vegetation map has a biodiversity target set by the
National Spatial Biodiversity Assessment. This vegetation map, with minor refinements, was
used to define 68 vegetation types for Mpumalanga, shown in Figure 3.1.
With vegetation types defined and mapped, it is possible to assess their ecosystem status.
Ecosystem status reflects the ecosystem’s ability to function naturally, at a landscape scale
and in the long term. The single biggest cause of loss of biodiversity in South Africa is the
loss and degradation of natural habitat. As the natural habitat in an ecosystem is reduced
and degraded, its ability to persist is compromised. The degradation process is characterised
by: loss of ability to deliver ecosystem services; loss of biodiversity, including local species
extinctions; and irreversible damage to ecological processes. All these combine, eventually
leading to ecological collapse (Rouget et al. 2004).
LISTING OF THREATENED
ECOSYSTEMS IN TERMS OF THE BIODIVERSITY ACT
The Biodiversity Act provides for listing threatened and protected ecosystems as follows:
52 (1) (a) The Minister may . . . publish a national list of threatened ecosystems in need
of protection.
(b) An MEC for environmental affairs may . . . similarly publish a provincial list of
threatened ecosystems.
52 (2) The following categories of threatened ecosystems may be listed in terms of
subsection (1):
‘Critically endangered’ ecosystems – that have undergone severe ecological
degradation and are at an extremely high risk of irreversible transformation;
‘Endangered’, or ‘vulnerable’ ecosystems – being categories of reduced
degradation and risk, each less than the previous category above;
‘Protected’ ecosystems – being ecosystems that are not threatened but
nevertheless are worthy of special protection.
NOTE: DEAT and SANBI are in the process of developing criteria for identifying and listing
threatened and protected ecosystems. Systematic biodiversity plans such as the MBCP will
provide an important basis for identifying these ecosystems.
The purpose of defining vegetation types in terms of their ecosystem status is to identify
ecosystems at risk. The ecosystem status categories are similar to those used by the IUCN for
species: Critically Endangered (CR), Endangered (EN), and Vulnerable (VU). These categories
are also used in the National Spatial Biodiversity Assessment (Driver et al. 2005). A vegetation
type is allocated an ecosystem status based on the proportion of its original natural
M P U M A L A N G A
habitat that remains. The classification system and categories used here are illustrated in
Biodiversity
Figure 3.2. In the MBCP analysis the endangered category is split in two in order to identify
those ecosystems closer to critically endangered status.
CONSERVATION PLAN HANDBOOK