Wetlands comprise fresh and saltwater marshes, swamps, bogs, flooded forests that hold water long enough for plants and soils to develop. They are essential as they provide multiple ecosystem services such as food, building material, supporting biodiversity, flood control and carbon sequestration. The importance of their use will increase in the face of an urgent need to counter the effects of global warming, in urban and peri-urban areas, where it will be crucial to improve protection from heavier and less predictable floods, and to improve local climate regulation during hot summers.
Globally approximately 87% of wetland extent has been lost due to agriculture, development draining and infilling. Restoration efforts are needed for these ecosystems as they are under threat. The benefits that will arise from wetland restoration include:
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An increase in biodiversity
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Filtering freshwater
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Protect against storms and floods
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Increase tourism
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Assist with carbon storage
There is an urgent need in South Africa to restore wetlands that include rivers and estuaries. As individuals, we can improve the health and functioning of wetlands by preventing plastic pollution and dumping of waste such as garden refuse and building rubble in wetland areas. Sewage and agricultural run-off to wetlands must be controlled. Our wetlands are in serious trouble due to the malfunctioning of wastewater treatment plants. High organic loads from sewage spills reduce available oxygen, killing animal life and causing toxic algal blooms.
Estuaries the meeting place of land and sea, -where salt and freshwater mix - are particularly sensitive to human pressures. South Africa has close to 300 estuaries that can be considered “super” ecosystems as they cover 2% of South Africa’s coastline but contribute R4.2 billion per annum to the economy. Estuaries are focal points for development, tourism and recreation. They support biodiversity, livelihoods and marine fisheries.
However specialized plants habitats that only occur in estuaries such as salt marsh and mangroves are under pressure. Nearly 30% of salt marsh has been lost nationally due to agriculture and development removing these areas. Estuarine fish are overfished with stocks of the five most important species collapsed. Release of effluent from wastewater treatment plants and stormwater run-off pollutes urban estuaries.
The Shallow Water Ecosystems Research Chair at Nelson Mandela University studies the restoration of estuaries looking at innovative methods for water quality improvement, advising on the best sites for habitat restoration and improvement of health of sensitive mangrove and salt marsh habitats.
A socio-ecological framework has been developed for the restoration of estuaries that considers both ecological health, ecosystem services and societal benefits. This is vital in addressing the gap between legislation, governance, implementation, and social commitment.
This framework for the restoration of estuaries helps managers and policymakers to make informed environmental management decisions that consider both ecological and socio-economic factors. This research is aligned with the United Nations Decade of Ecosystem Restoration and priority sites for action have been identified nationally.
Research is funded by the Water Research Commission, Department of Science and Innovation and National Research Foundation. Research findings are communicated across the science-policy-practice forum. Innovative methods for water quality improvement have been investigated at Swartkops Estuary that are integrated in the Estuary Management Plan implemented by the Department of Water Affairs, provincial government and metro. Stormwater improvement, the use of natural infrastructure and artificial wetlands for water quality treatment were researched. Nature based solutions for mitigation of watershed pollution are being investigated at Knysna Estuary together with the South African National Parks and Knysna Basin Project. Research results provide input to the future ecological and social well-being of all estuaries in the country and those dependent on them.
Seven estuaries (Groot Berg, Swartkops, Orange, Olifants, Gamtoos, Gouritz, and Klein Brak) with the largest salt marsh area losses were identified for restoration in South Africa. Actions identified for implementation are the removal of agriculture, restoration of salt pans, monitoring of freshwater flow, bank restoration, improving of water quality and the removal of alien invasive plants. Aquatic invasive weeds such as water hyacinth clog up waterways, cause deoxygenation and prevent fish movement. Action research (a learning-by-doing) approach is needed to establish best methods and practices for restoration; for example on how to convert agricultural lands back to salt marsh.
Other actions that are needed to restore estuaries are, for example:
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Reinstate freshwater flows to estuaries, prevent over-abstraction and lowering of the groundwater table.
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Reduce the volume of effluent from Wastewater Treatment Works into and upstream of estuaries.
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Improve water quality of return flow from agriculture in catchments.
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Control and reduce urban stormwater runoff into estuaries by for example using sustainable drainage systems (SuDS), and
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Remove poorly planned low-lying infrastructure in the estuary functional zone.
In South Africa, the Expanded Public Works Programmes have played a vital role in freshwater wetland restoration and creating jobs to reduce local unemployment, mainly in rural areas. Nevertheless, a new policy is required that will address estuary restoration to manage efforts and link to existing programmes. In South Africa marine and coastal restoration is structured through a framework designed to limit environmental impacts from development rather than through a tailored framework meant to achieve net environmental benefits.
Strategic interventions across multiple sectors to restore wetland health and protect benefits to people are needed. There are opportunities for flagship programmes developed in a collaborative manner between government agencies and civil society. The United Nations Decade of Ecosystems Restoration 2021-2030 makes restoration and protection of wetlands an imperative at a global scale. This call to arms, aims to scale up the restoration of degraded ecosystems to combat the climate crisis and enhance food security and biodiversity. It also presents a host of funding opportunities through climate finances instruments and Ecosystems-based Adaptation global funds.
Restoration provides opportunities for innovation through transdisciplinary approaches. Research can harmonize links between disciplines in a co-ordinated and coherent whole that focuses on “real-world” system problems. The involvement of stakeholders and communities is essential.
Restoration research provides opportunities for training and capacity building across disciplines. By celebrating successes, we will ignite hope and inspire the next generation of thinkers and change-makers (#oceanoptimism, #GenerationRestoration). It is important to communicate the message that individuals can make a difference.
Janine Adams
with input from
Jongo Gcina, Rachel Kibble, Anesu Machite
DSI/NRF Research Chair: Shallow Water Ecosystems
Deputy Director: Institute for Coastal and Marine Research,
Department of Botany, Nelson Mandela University
