NEWS and 70 % of irrigated agriculture .
Known for being marsh pits of still water – between aquatic and terrestrial systems supporting vegetation adapted for saturated soils – wetlands function as water-purifying bodies . They play a role in slowing down floodwaters , are natural filters and provide food and shelter for nearby animals .
Wetland ecosystems are threatened mainly by invasive alien species , erosion , developments in and around them , pollution and excessive nutrients , slash-and-burn agriculture and mining .
Conserving them is of great importance as the world is losing them three times faster than forests , with nearly 90 % of them having degraded since the 1700s , according to Ramsar .
South Africa ’ s wetlands include the Blesbokspruit wetlands , with some in the Ntsikeni Nature Reserve , Natal Drakensberg Park , Prince Edward Islands , St Lucia , Bot-Kleinmond Estuarine and Verlorenvlei .
Verlorenvlei is among the most important wetlands and the largest on the West Coast , at 13.5 km long and 1.4 km wide . The system has been
reported to be drying up , with the surface water in the vlei being saline and unusable . The vlei houses more than 4,000 birds and is a space of significance for conservation of the birds and other biodiversity .
Last year , in an effort to improve Cape Town ’ s water bodies , the City of Cape Town restored an old wetland , the
Zandvlei estuary . The improvement of the Muizenberg vlei aimed to revive the wetland habitat , though residents had concerns about the vlei being polluted , as another in the area had been .
One of the country ’ s biggest wetlands , iSimangaliso Wetland Park , which was listed as South Africa ’ s first World Heritage Site in 1999 , will be on the receiving end of space-based sensors for wetland monitoring .
The three-year project , funded by the Water Research Commission and led by the Council for Scientific and Industrial Research , will focus on the Maputaland Coastal Plain . Wetlands make up a quarter of the coastal plain , an area rich in wetland biodiversity , swamp forests , mangroves and floodplain forests , grass and sedge wetlands .
The plain is in northern KwaZulu-Natal , running along 8,000km 2 of the eastern coastline . The focus will be on monitoring changes in wetlands that are often hidden beneath forest canopies and other vegetation , or exist as temporary pans following rains .
The Water Research Commission ’ s research manager overseeing the project , Bonani Madikizela , said : “ Many of the wetlands of the Maputaland Coastal Plain are under severe stress , yet they are so important to the marginalised sectors of our communities that rely on them for food and other ecosystem services .”
Dr Heide van Deventer , who is leading the project , said remote sensing could be valuable for monitoring the coastal plain ’ s wetlands as these can be difficult to access due to muddy conditions and potential encounters with hippos , crocodiles , buffaloes and elephants .
“ Areas in need of rehabilitation could be more easily identified and prioritised [ through the programme ]. If successful , the intention is to incorporate this capability into the National Wetland Monitoring Programme .”
Despite wetlands taking up less than 3 % of South Africa ’ s land , the benefits they provide are proportionately high as they provide water purification , nutrient cycling , carbon storage , storm protection , recreation and harvesting of food directly from nature . Protecting them could be of utmost importance for not only biodiversity , but also for the country ’ s water quality and resources , and society at large .
Figure 2 . General view during the World Wetlands Day at Bayhead Natural Heritage Site on February 2 , 2020 , in Durban , South Africa . ( Photo by Gallo Images / Darren Stewart )
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