Wetlands are some of the planet’s most important ecosystems. They’re a haven for wildlife, they filter pollution and they’re important stores of carbon.
But they’re also one of the Earth’s most threatened habitats. Some 85 per cent of wetlands present in 1700 were lost by 2000, many drained to make way for development, farming or other “productive” uses. Disappearing three times faster than forests, their loss spells an existential threat for hundreds of thousands of animal and plant species.
“Healthy wetlands – critical for climate mitigation, adaptation, biodiversity, and human health and prosperity – punch above their weight in terms of benefits,” says Leticia Carvalho, Principal Coordinator for Marine and Freshwater at the United Nations Environment Programme (UNEP). “Making sure that they continue to deliver vital ecosystem services to humanity requires… their prioritization, protection, restoration, better management and monitoring.”
Carvalho made the comments on the eve of World Wetlands Day, which falls on 2 February. This year, for the first time since it was established by Ramsar Convention on Wetlands in 1972, World Wetlands Day is being observed as a United Nations international day.
Wetlands, which include marshes and peatlands, are the unsung heroes of the climate crisis. They store more carbon than any other ecosystem, with peatlands alone storing twice as much as all the world’s forests. Inland wetland ecosystems, also absorb excess water and help prevent floods and drought, widely seen as critical to helping communities adapt to a changing climate.
This is why Carvalho says the protection of wetlands are a priority for UNEP and a special focus of the UN Decade on Ecosystem Restoration, a global push to protect and revive the natural world.
“It’s encouraging that there is increasing recognition of wetlands as an invaluable but overlooked nature-based solution,” she said. “COP 26 started to shine a spotlight on the role of finance and political will. More of both need to be channeled towards wetlands, enshrined in countries’ Nationally Determined Contributions, and better integrated into development plans,” she adds.
Wetlands built by humans, such as reservoirs, also contribute to human well-being and have other benefits. One project in the Baltic, for instance, aims to improve water quality in lagoons polluted by fertilizer run-off by using floating, vegetation-rich, wetlands to remove nutrients such as nitrogen and phosphorus.
Finally, wetlands, teeming with species, are a key ally in our fight to stop biodiversity loss. Over 140,000 described species – including 55% of all fishes – rely on freshwater habitats for their survival. Freshwater species are important to local ecosystems, provide sources of food and income to humans and are key to flood and erosion control. Yet wetland species are going extinct more rapidly than terrestrial or marine species, with almost a third of all freshwater biodiversity facing extinction due to invasive species, pollution, habitat loss and over-harvesting.
The good news is that protection, sustainable management and restoration of wetlands work. Improving management of wetlands brings health, food and water security benefits – critical to the health and livelihoods of 4 billion people reliant on wetlands’ services, says the Global Wetland Outlook. Under Sustainable Development Goal 6, Target 6, all countries are committed to protecting and restoring wetlands by 2030, and UNEP has a special role in helping to monitor and achieve that target.
The Okavango Delta in Botswana and the Pantanal in Brazil are iconic examples of inland, vegetated wetlands teeming with wildlife. But wetlands come in many shapes and sizes and are uniquely under pressure from demographic and development forces, notably from agriculture. Check out these five unexpected wetlands to learn more.
Healthy wetlands – critical for climate mitigation, adaptation, biodiversity, and human health and prosperity – punch above their weight in terms of benefits.
1. Artificial and constructed wetlands
Not all wetlands are permanently wet and not all wetlands are natural. Artificial wetlands, such as reservoirs and fish ponds, help cool the planet and soak up carbon. Constructed wetlands make use of the natural purification processes of vegetation, soils and microbes to remove contaminants from wastewater, and when designed right can serve as biodiversity hotspots and migration stopovers. This relatively low-cost technology improves water security, making it important for climate change adaptation.
2. Arctic peatlands
The northern circumpolar region holds almost half of the world’s soil organic carbon, largely in the form of permanently frozen peat. Given that the Arctic is seeing the fastest rate of global heating, the big fear is that, as the ice around them melts, they degrade and begin to emit masses of stored carbon dioxide as well as methane, potentially causing a catastrophic climate change tipping point.
3. Soda lakes
Most inland wetlands are freshwater ecosystems. Soda lakes, like Lake Van in Türkiye and Lake Bogoria in Kenya, are strongly alkaline and contain water that is undrinkable, but they provide valuable ecosystem services, including sought-after minerals and enzymes. These unusual habitats also provide opportunities for recreation, education and research.
4. Saltwater marshes
Not all wetlands are freshwater. Saltwater or tidal marshes, found in coastal regions particularly at middle to high latitudes, are important habitats for diverse wildlife, fish reproduction, carbon storage and coastal protection. However, they too are under threat: “Depending on the amount of sea-level rise, 20-90 per cent of current coastal wetlands may be lost by the end of the century,” says UNEP’s Making Peace With Nature report.
5. Peatland swamp forests
Lowland forest ecosystems, or swamp forests, formed on peat soils are found mainly in the islands of Indonesia and Malaysia. Many of them have been deforested and drained to make way for palm oil plantations but there is growing recognition of their value as wildlife hotspots and carbon sinks. Peatlands cover only 3 per cent of the Earth’s land surface and yet are our largest terrestrial organic carbon store. Protecting and restoring peatlands can reduce global greenhouse gas emissions by 800 million tons per year – equivalent to Germany’s annual emissions, according to a recent UNEP report. Learn more through this virtual journey.
The UN Decade on Ecosystem Restoration 2021-2030, led by the United Nations Environment Programme, the Food and Agriculture Organization of the United Nations and partners, covers terrestrial as well as coastal and marine ecosystems. A global call to action, it will draw together political support, scientific research and financial muscle to massively scale up restoration. Find out how you can contribute to the UN Decade.
For more information, please contact Lis Mullin Bernhardt: lis.bernhardt@un.org
