Why wetlands are vital for biodiversity and climate change

Angela Glienicke

February 23, 2023

Halfway between land and water, wetlands are one of nature’s little gems. Brimming with life and vital for fighting climate change, 40% of all plants and animals live and breed in wetlands and more than one billion people depend on them for their living.

But for decades, we’ve witnessed their destruction. Greenpeace has campaigned to protect these stunning habitats. Like linking cattle ranchers to the Pantanal wetlands 2020 record fire, uncovering peat bog burning in the UK or exposing the role of palm oil companies in the destruction of Indonesian peatlands.

Here’s why we need to protect and restore nature’s wetlands.

Chunky textured tree trunks protrude from water. — The Bald Cypress swamp in Louisiana in the USA.

What are wetlands?

Wetlands are places where land is covered by freshwater, saltwater or something in between. They can stay this way for years or decades, or change by season. Their water can come from nearby rivers, lakes or the sea, or seep up from a spring in the ground.

Plants that are adapted to the watery soil live in different types of wetlands. They’re an ideal habitat for many animals too, including hundreds of birds, crocodiles and fish.

Bright yellow frog with giant blue-black cheeks — The Indian Bullfrog lives in freshwater wetlands in South and Southeast Asia. Monsoon rains mark the breeding season, when male frogs change colour to yellow to attract mates.

Wetlands exist in every climate and continent except Antarctica. They vary in size from small prairie potholes to huge salt marshes.

The largest inland tropical wetland is the Pantanal in South America. It’s slightly bigger than England at 42 million acres, and stretches mainly across Brazil but also Bolivia and Paraguay. About 80% of the Pantanal’s floodplains are submerged during the rainy season. It’s one of the most biodiverse biomes in the Americas, nurturing many plants and providing a diverse habitat for many species.

Land and water stretch into the horizon, with mountains in the distance. — The Pantanal has four designated ‘Wetlands of international importance’. © Markus Mauthe / Greenpeace

3 jaguars swim in water, with vegetation behind them — Jaguars in the Pantanal wetlands © Carlos Eduardo Fragoso / Greenpeace

Types of wetlands

Wetlands are categorised by where they get their water from and what types of plants mainly grow in them. The three major types are:

Swamps – these are always saturated with water and mainly have woody plants, such as trees and shrubs. You can get both freshwater and saltwater swamps.
Marshes – these can also be freshwater or saltwater. Every now and again these areas are flooded by a nearby lake or river, or by tides from the sea. This means the water levels can change a lot.
Bogs – these are freshwater wetlands with soft ground. You tend to find them more in the colder climates of Europe, Asia, North America or even the Arctic. They are called moors in Europe and are usually formed when a lake fills with plant debris. Peat Peat is an organic wetland soil made from partly rotted plant debris. Healthy peatlands act as a carbon sink. Growing plants remove carbon from the atmosphere. When plants die, they normally rot down and return the carbon to the atmosphere. But plants only rot down partly in a year-round waterlogged wetland, so carbon collects in them as peat. builds up where the water mostly comes from rain and snow.

Two boys in a long wooden boat row past lush green banks on a river. — Sons of local fishermen canoe on the Serkap river, in peatland rainforest in Kampar in Indonesia.

Mist settles on a landscape forest and water — The Kemeri Bog, one of Latvia's biggest wetlands.

Does the UK have wetlands?

The rainy weather in the UK provides ideal conditions for wetlands to form. There are currently 175 sites registered as wetlands of international importance. Some of the best-known wetlands are worth a visit, like: Slimbridge in Gloucestershire, the wetland centres in Arundel in the South Downs and London, and the Cley Marshes in Norfolk.

Grass-like tufts lead down to sand and saltwater. — The Cley Marshes in Norfolk are part of a protected “site of special scientific interest” (SSSI).

Why are wetlands important for biodiversity and fighting climate change?

Wetlands play a vital role in the fight against climate change. They can act as a shield against the most extreme weather events. By soaking up heavy rainfall and improving water flows, they help with preventing flooding. They also offer protection against droughts by storing and slowly releasing water. And wetlands can store twice as much carbon than all the world’s forests!

With changing water levels and a mix of water and land, wetlands are biodiversity hotspots. These biological super systems have rich plant life that provides food and breeding grounds for countless animals. In the world’s freshwater wetlands alone, about 100,000 different species of animals have been identified so far.

A black and white bird in mid-flight with buffalos behind — A Pied kingfisher flies past buffalo grazing in the Chibayesh marshland in Iraq

A small boat travels on a vast wetland — The Everglades Wetlands in the US is home to one of the largest ecological conservation efforts in the world. But time is running out, as global warming threatens more than 2000 animals and plants living in this subtropical wilderness.

How are wetlands threatened?

Wetlands are one of the most threatened habitats in the world. As much as 87% of the world’s wetlands have been lost over the past 300 years. Urbanisation, intensive farming and climate change are major threats to wetlands. Increasing temperatures and droughts can turn wetlands from carbons sinks to carbon sources. And rising sea levels can submerge coastal wetlands.

Small boat travels along a small stream in the middle dry land — An aerial view shows the dried-up bed of Iraq’s southern marshes, which are gradually shrinking.

For example in China, one of the biggest threats to coastal wetlands is the speed and scale of land reclamation projects. Illegal occupation and poor supervision of land use afterwards have led to damage that threatens life in coastal wetlands. It affects not only plant and animal life, but also fishing communities. Many that have been closely bound up with the coastal wetlands for generations.

A loose group of people carrying spades and large buckets strapped across their shoulders. They fade into the horizon as they walk through muddied water. — Mud snail fishermen wade into retreating tides in China. They walk about 5-10km from the beach to dig for mud snails before taking a boat or walking back.

In Argentina, the ‘Wetlands Law’ is a popular solution to the burning crisis facing its wetlands, grasslands, plantations and forests. More than 800,000 hectares burned after two years of extreme drought in the Corrientes area alone. Burning pastures for farming also adds to the risk of fires going out of control. Estimates suggest humans cause 95% of these burns in this region. The wetlands law would create protected zones and boost budgets to enforce it. But the bill has been stalled in congress for a decade and intentional burning goes unprosecuted.

A capybara stands on dry land with crisp golden grasses. Smoke rises into the air on the horizon. — Corrientes in Argentina faced fires after two years of extreme drought dried out land and increased fire risk. Many fires were caused by intentional or negligent human activity.

Closer to home, British wetlands are threatened too. Greenpeace investigative journalists at Unearthed found England’s largest protected wildlife site is at risk. The Wash contains important wetland habitats, including mud flats, salt marshes and freshwater marshes. But reporters uncovered a lack of monitoring that’s leaving the Norfolk coastline at greater risk of decline.

Unearthed also documented fires set to heather on peatlands in Northern England’s National Parks – despite a partial ban. Peatlands are the UK’s biggest natural carbon store on land. Burning them degrades them, releases CO2, increases the risk of floods and can damage water quality.

In Scotland, conservationists admit that there is a long way to go before the Flow Country and other peatlands are fully restored. More than 148,000 acres of the Flow Country alone remain unnaturally forested today.

Fire turns ground to ash and smoke clouds go into the air, as a man in fireproof gear walks carrying fire extinguisher. — Heather is set alight on peatlands in the North York Moors National Park for grouse-shooting. © Steve Morgan / Greenpeace

How can we protect wetlands?

Protecting and restoring wetlands is crucial in the fight against climate change. And the drive for this is gaining momentum. Government action and conservation efforts are needed to stop the destruction of habitats and ensure nature is able to thrive for the future.

Protections for water quality, biodiversity and habitats must be put into place. Along with urgent, regular, ongoing restoration and monitoring to help conserve wetlands. Such as planting seedlings in mangrove swamps or rewetting swamps to turn them back into carbon sinks.

A man with a large measuring device in a forest — A wetland restoration specialist for The Nature Conservancy checks a monitoring gauge in a US swamp.

Reintroducing beavers also helps to create wetlands habitats. They were extinct in many countries, including the UK for 400 years. Beavers eat bark, gnaw on twigs and build dams. This creates ponds, which slows water flow and forms spaces that support a wide variety of life.

A beaver dips its front paws into water by a grassy riverbank — Eurasian/European beaver on riverbank.

To protect wetlands worldwide, the UK government should tackle the causes of environmental destruction. This includes: strengthening regulations on imported products (like soya, meat or palm oil) to prove they’re not linked to ecosystem damage or human rights abuses; ending finance to nature destroyers; and reducing meat and dairy production and consumption by 70% by 2030.

For UK wetlands, a current threat is a proposed bill that would affect laws that protect nature. Habitats Regulations safeguard wildlife and natural spaces. If parliament passes the new bill, it will potentially cancel all existing laws from European Law by the end of 2023 – including the Habitats Regulations. We need to ensure Habitats Regulations are not removed.