What are wetlands and why does our planet need them?

Did you know wetlands have their very own day? It’s true – International Wetlands Day falls on 2 February, so let’s look at what wetlands are, why they are so important, and what we can do to increase their number.

What defines a wetland?

Wetlands are ecosystems where water covers the soil permanently or seasonally, such as marshes, bogs, and swamps. They are vital to the planet because they act as natural carbon sinks, prevent flooding, and support 40% of the world's biodiversity.

Ramar's official definition of a wetland is: 

areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres. (Ramsar, 1971)

Thus, a wetland is a piece of land that is covered by water either permanently or during certain seasons. The water in wetlands comes from rainfall, groundwater, or nearby bodies of water. Most wetlands are either flooded or remain consistently moist. remain consistently moist.

5 quick facts about wetlands 

If you only have a minute, here is why wetlands are considered the "superheroes" of our natural world:

• Despite covering only 6% of the Earth’s land surface, wetlands are home to 40% of all plant and animal species.
• Peatlands (a type of wetland) store twice as much carbon as all the world’s forests combined, making them vital in the fight against climate change.
• Wetlands act as the "Earth's kidneys," filtering out pollutants, sediment, and toxins from water before it reaches our oceans and aquifers.
• Wetlands are vanishing three times faster than forests. Since 1970, we have lost 35% of the world’s remaining wetlands.
• Coastal wetlands, like mangroves and salt marshes, save more than $620 million in property damage every year by acting as natural buffers against storm surges and floods.

What are the different types of wetlands? 

While all wetlands are defined by the presence of water, they are far from identical. Depending on the soil, climate, and water source, they generally fall into four primary categories. Understanding these differences is key to understanding how they protect our environment.

1. Peatlands: The Earth’s natural freezer

Peatlands are a specific type of wetland where the ground is made of peat, a thick layer of partially decayed organic matter. Because these areas are waterlogged, oxygen can't reach the soil, which stops plants from fully decomposing and "freezes" their carbon in place.

• Sub-types: This category includes both Bogs (fed by rain and acidic) and Fens (fed by groundwater and nutrient-rich).
• Key feature: They cover only 3% of the Earth’s land but store twice as much carbon as all the world’s forests combined.
• Benefit: Protecting peatlands is the single most effective way to prevent massive "carbon bombs" from entering the atmosphere.

2. Marshes: The grasslands of the water

Marshes are the most common wetlands. They are frequently or continually inundated with water and are characterised by soft-stemmed vegetation that "emerges" from the water's surface.

• Key vegetation: Reeds, grasses, and sedges.
• Water source: Mostly surface water (rivers or lakes).
• Benefit: They act as a massive natural sponge, absorbing excess water during heavy rains to prevent downstream flooding.

3. Swamps: The flooded forests

Unlike marshes, swamps are defined by their woody plants. They are often found in low-lying areas near large rivers or coastal regions where the water moves very slowly.

• Key vegetation: Trees (like Cypress or Mangroves) and shrubs.
• Water source: Floodplains and high groundwater tables.
• Benefit: Swamps are biodiversity hotspots; mangrove swamps, in particular, are vital for protecting coastlines from erosion and storm surges.

How do wetlands protect the planet and humans?

Wetlands are natural water filters that capture pollutants, such as phosphorus and heavy metals. Many animals thrive in wetlands, which makes them vital for maintaining natural, biodiverse habitats.

According to the Wildfowl & Wetlands Trust (WWT), an incredible 40% of the world’s plants and animals depend on wetlands. As wetlands reduce in both number and size, the impact on animal life and biodiversity is huge. Right now, 25% of wetland species face extinction.

Wetlands also protect against floods by letting water sink into the ground, so when they disappear, the risk of flooding increases. They are also useful in times of drought, because they store water that can then be used.

Wetlands are also one of the planet's best carbon sinks. They capture and store carbon dioxide from the atmosphere and so counteract climate change. The maths is simple. Fewer wetlands means more damage to the planet. 

Finally, wetlands also play a major social role in society. They are excellent tourist spots and great for fishing, birdwatching and other outdoor activities. As untouched nature becomes more scarce, we need to make the most of it.

What are the biggest threats to wetlands?

Wetlands are frequently found near agricultural areas, forests, and urban developments. However, these areas can become threatened when they are not managed sustainably. Often, excavation occurs to create space for farming and forestry. Additionally, pollution, invasive species, and climate change pose significant threats to the planet's wetlands.

Sadly, many natural wetlands have disappeared, and the problem is getting worse. We have taken these places of natural beauty for granted for too long, and now we need to do something about it.

The statistics make for grim reading. Again, according to the WWT,35% of our wetlands have disappeared since 1970, and in the UK, 86% of rivers don't meet good ecological status. Something clearly needs to change. 

Can we restore or create new wetlands?

It is possible to build new wetlands or restore damaged wetlands. Most countries encourage the idea, and there is often funding available to landowners so they can build and manage wetlands. Conservation projects also help preserve, protect and rebuild areas of natural beauty and importance. 

We all hope that these initiatives can turn the tide, but there is so much work to be done. Both companies and we as individuals need to increase our commitment to wetlands. The more effort we put in to increase awareness, the better our chances of forcing positive changes.

Support a wetland biodiversity project

Biodiversity is a central part of everything we do, so you can also contribute to specific projects, including our work to restore wetlands. In return, we send you an annual activity report so you can get to know more about the progress we are making as a result of your support.

Here are three water conservation projects you can support to help protect wetlands: 

• The Pézarches forest ponds near Paris, France
• The Thisted wetland in Thisted, Denmark 
• The Nysum restoration project in Northern Denmark