Mpumalanga Biodiversity Conservation Plan Handbook - bgis-sanbi

MPUMALANGA BIODIVERSITY CONSERVATION PLAN HANDBOOK
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Malachite Kingfisher
Alcedo cristata
Because of the
ecological, social and
economic importance of
wetlands and their
threatened status in South
Africa, an extensive
inventory of wetlands,
their status and the
threats they face is
underway. The inventory
is spearheaded by the
Department of
Agriculture and Land
Administration but
includes a wide range of
stakeholders including
government departments,
NGOs, conservation
bodies and research
institutes.
cover slows runoff, filters and purifies water and reduces the impacts of droughts and floods
by regulating stream flow. They provide special habitats for many species of plants and
animals. Besides these benefits, wetland vegetation also provides economic resources such
as grazing, food, medicinal plants and natural fibre for thatch and craft making.
Wetlands are controlled by the same basic ‘drivers’ as rivers. These features define their
health and sustainability. A key property of wetlands is that they present a convergence of
aquatic and terrestrial biodiversity at important positions in the landscape. It is here, as well
as in rivers, where the health of key components of natural ecosystems can best be observed
and measured. Our wetlands are typically variable, with over 90 different wetland biodiversity
features recognised in the MBCP. These are based on a functional and Ecoregion
level 2 classification as a surrogate for wetland biodiversity types. All wetlands may be
allocated into four functional categories.
CATEGORIES OF WETLANDS
SEEPAGE WETLANDS – are generally seasonal, small and widely scattered. Often referred
to as seeps or sponges, they mostly occur on obvious slopes and in upland areas. They are
sometimes linear, across the slope and may be associated with bands of impermeable rock
which provide an unexpected ‘perched water-table’. These are the least obvious wetlands
as they are the most temporary and not located in obviously wet valley-bottom landscapes.
VALLEY-BOTTOM WETLANDS – occur in bottom-lands and are generally wetter, and wet
for longer periods, than seeps. In headwater areas they typically occur as seasonally waterlogged,
shallow grassy valleys (vleis). In the mid and lower reaches of rivers they are also
associated with streams and river banks, especially within the floodline. Valley-bottom
wetlands include floodplains of the lower reaches of larger rivers, subjected to high-volume
flood events.
PANS – are shallow, usually seasonal bodies of open water; often circular and not directly
connected to river systems by surface flow. Essentially they are internally draining systems
that may contain either fresh or saline water, depending on local soil conditions. They may
be temporary or perennial. Pans on different soils and at varying altitudes have substantially
different ecological characteristics.
LAKES AND DAMS – there are no true lakes in Mpumalanga. Strictly speaking, lakes are
natural impoundments within the continuous river line. Dams are artificial impoundments
that are not considered as wetlands as we have no natural fauna and flora that are adapted
specifically to lake-type environments. The small ‘lakes’ in the Chrissiesmeer area are in
fact pans, occasionally interconnected by wet-season overflows.
M P U M A L A N G A
Biodiversity
CONSERVATION PLAN HANDBOOK