By The United Nations Environment Programme (UNEP)
UNEP Europe Office
The Marismas (wetlands) of the Coto Doñana National Park, Spain (2014) by © GRID-Arendal/Peter ProkoshOriginal Source: http://www.grida.no/resources/1365
What are wetlands?
Wetlands are environments covered by freshwater, saltwater, or a mix, and are present in coastal and inland areas. They are found across the world, ranging from giant deltas and mighty estuaries and mudflats, to floodplains and peat bogs. Sadly, they are often undervalued.
Mangrove roots, Isla Santay Wetland, Ecuador (2014) by © Wladimir Torres (WLADO)The United Nations Environment Programme (UNEP)
Why are wetlands important?
Wetlands serve as natural wastewater treatment services and are carbon-storing champions. They provide clean water, flood control, shoreline and storm protection, materials, medicines, and vital habitat for an important biodiversity.
Wetland at Ras al Khaymah, United Arab Emirates (2014) by © GRID-Arendal/Rob Barnes under licence from AGEDIOriginal Source: http://www.grida.no/resources/8926
What are the different types of wetlands?
These ecosystems take many forms like rivers, marshes, peat lands, mangroves, mudflats, ponds, swamps, lagoons, lakes, and floodplains. Most large wetland areas often include a mix of different wetland types.
Wetlands in the agriculture landscape near Amsterdam, The Netherlands (2014) by © GRID-Arendal/Peter ProkoshOriginal Source: http://www.grida.no/resources/1688
Wetlands and agriculture
Wetlands support agriculture as a source of water for crops and livestock and as habitat for aquaculture. These ecosystems provide fertile lands and support the cultivation of rice, a staple in the diet of half the world’s population.
White Storks (Ciconia ciconia) nesting on palms, Coto Doñana National Park, Spain (2014) by © GRID-Arendal/Peter ProkoshOriginal Source: http://www.grida.no/resources/1358
Biodiversity in wetlands
Several thousand plant species grow in wetlands, ranging from mosses and grasses to shrubs and trees. A wide variety of animal species also live in wetlands.
Sumatran tiger (Panthera tigris) (2014) by © GRID-Arendal/Peter ProkoshOriginal Source: http://www.grida.no/resources/3054
Fauna
Birds, including ducks, geese, kingfishers, and sandpipers use wetlands as pit stops during long migrations, providing them with protection and food. Mammals like otters, beavers, and even tigers rely on wetlands to find food and shelter.
And, of course, wetlands are home to many types of fish.
Food from Wetlands (2020) by © UNEP/Georgina SmithThe United Nations Environment Programme (UNEP)
Wetlands and people
It is estimated that more than a billion people in the world live thanks to wetlands, in particular from fishing, rice cultivation or handicrafts. In addition, sectors such as travel and ecotourism, water transport and aquaculture depend on the health of these ecosystems.
Northern Tamandua (Tamandua mexicana), Isla Santay, Ecuador (2019) by © Ángel Fabricio Bayona CalderónThe United Nations Environment Programme (UNEP)
Ecological benefits of wetlands
Wetlands provide a range of valuable services for society and the environment. These include environmental, economic, educational, cultural, recreational, and aesthetic benefits. As well as sustaining many plant and animal species, they improve water quality, reduce erosion and flooding. Wetlands even moderate the effects of climate change.
Shoebill (Balaeniceps rex), Mabamba Bay Wetland, Victoria Lake, Uganda (2015) by © GRID-Arendal/Peter ProkoshOriginal Source: http://www.grida.no/resources/2367
How do wetlands naturally filter water?
Thanks to their flora and soil, wetlands trap pollutants such as phosphorus and heavy metals. They transform nitrogen into a form that is easier for plants to take in. Finally, they physically and chemically break down bacteria.
Elephants in the water, Okavango Delta, Botswana (2016) by © GRID-Arendal/Yannick BeaudoinOriginal Source: http://www.grida.no/resources/9638
How wetlands mitigate climate change?
Wetlands are very effective at capturing CO2. They can store 50 times more carbon than rainforests and help trap gases and heat that contribute to climate change. They naturally degrade plant and animal waste, as well as other high-carbon materials from the surface of the water.
Kids in the Wetland, Isla Santay, Ecuador (2014) by © Wladimir Torres (WLADO)The United Nations Environment Programme (UNEP)
Pollution in wetlands
Pollutants such as contaminated sediments, fertilizers, human sewage, animal waste, road salts, pesticides and heavy metals can exceed the wetland's natural ability to absorb such pollutants and cause degradation. In addition, air pollution, leakage from landfills, boats stirring up, and pollutants around marinas dangerously affect wetlands and the quality of their water.
Cape Flora, Franz Josef Land, Russian Arctic National Park (2016) by © GRID-Arendal/Peter ProkoshThe United Nations Environment Programme (UNEP)
The Ramsar Convention on Wetlands
Named after the Iranian city, where it was adopted in 1971, it's the intergovernmental treaty that provides the framework for the conservation and wise use of wetlands.
The Ramsar Convention helps Contracting Parties designate their most important wetlands as "Ramsar Sites" and take action to manage them effectively, maintaining their ecological character.
Hippopotamus (Hippopotamus amphibius), Naivasha Lake, Kenya (2016) by © GRID-Arendal/Peter ProkoshOriginal Source: https://www.grida.no/resources/2491
Threats to wetlands not only affect biodiversity but also humans' health, subsistence, and wellbeing.
Let's not forget wetlands, and let's preserve and restore them!
Join us and learn more!
Additional learning resources:
- Ramsar Convention
- IUCN: Community Organizing- Toolkit on Ecosystems Restoration
- Society for Ecological Restoration:
International Principles and Standards for the Practice of Ecological Restoration
The United Nations Environment Programme (UNEP), Europe Office
