Deeply rooted myth or catastrophic ignorance? Why we are still draining wetlands

Instead of developing carbon-capturing technologies, we should protect what nature created millions of years ago—wetlands. These ecosystems store twice as much carbon in Poland as forests, filter water, stabilize the climate, and yet they are still considered useless. Is their drainage one of the greatest ecological absurdities of our time? Agnieszka Hobot discusses the secrets and underestimated power of these extraordinary areas with Professor Mariusz Lamentowicz.

Agnieszka Hobot: Wetlands are rarely mentioned in the media, so let’s start with the basics. What are they, and what should we know about them? A few days ago, we celebrated World Wetlands Day, so it’s worth reminding people of their importance.

Mariusz Lamentowicz: Wetlands seem like a simple topic, but in reality, they are quite complex. Everything depends on the definition—both in the scientific world and in general perception. A broad yet accurate definition comes from the Ramsar Convention Secretariat. According to it, wetlands include not only peat bogs, wet meadows, swamps, and salt marshes but also lakes and rivers. The boundary between open waters and wetlands is not fixed—there are gradual transitions, visible in river valleys where seasonally flooded peatlands appear. On the coast, there are salt marshes, while in forests, we find swampy habitats.

Only recently have we begun to fully appreciate the role of wetlands, particularly peat-forming ones, in the context of the entire environment. It is also interesting to consider the English terminology—”mire,” for example, refers to living peatlands, emphasizing that they are part of a larger system. On the other hand, some wetlands have been destroyed and converted into agricultural land, but their ecological potential remains enormous.

Agnieszka Hobot: Why, then, are wetlands so important?

Mariusz Lamentowicz: First and foremost—water. Many people don’t realize where the water they use every day comes from. Wetlands are natural reservoirs that regulate water circulation and improve its quality. We rely on water stored in wetlands, rivers, and lakes daily.

The second key aspect is carbon. For millions of years, wetlands have stored vast amounts of carbon, helping to stabilize the climate. Their history dates back hundreds of millions of years—since the Devonian period, when plants colonized the land, wetlands have been capturing carbon from the atmosphere. This process continued through the Carboniferous period, leading to the formation of coal deposits. Wetlands played a fundamental role in the evolution of the biosphere, influencing atmospheric composition and life conditions on Earth.

It was only in recent years, within the context of climate change, that we started to fully recognize their significance. It is surprising that it took so long. Today, besides anthropogenic emissions, we also acknowledge the impact of natural ecosystems on the climate—wetlands are absolutely crucial in this regard. They store more carbon than forests, meaning that their degradation can lead to the release of vast amounts of carbon dioxide and methane. Protecting and restoring them is one of the most important challenges in modern ecology.

Agnieszka Hobot: You touched on two extremely important issues that I also wanted to discuss. First, you mentioned that wetlands are a source of drinking water, but they also act as natural filters. Can you expand on that? Secondly, you brought up climate change, which is often linked to wetland drainage. How are these two aspects connected?

Mariusz Lamentowicz: Of course, but before we get into that, it is important to emphasize that wetlands provide many ecosystem services, not just water filtration or carbon storage. They are also a source of food for humans and animals—especially in the tropics, where swamp ecosystems are vital to the local economy. We may not notice it as much here, but wetlands include not only rivers and lakes full of fish but also plant habitats that have been used by humans for centuries.

Regarding water filtration, this process is easy to observe in agricultural landscapes, particularly in fields where small ponds or peatlands surrounded by willows and reeds trap pollutants—eutrophication is visible to the naked eye as aquatic plants absorb large amounts of nitrogen and phosphorus from fertilizers. Wetlands function in a similar way but on a much larger scale—they are natural treatment plants that capture nutrients and other pollutants before they reach rivers and lakes.

In urban areas, wetlands are becoming increasingly valued. We see the development of so-called urban wetlands—natural retention basins that not only improve water quality but also store water during droughts and prevent flooding when there is too much of it. This is a growing trend, though awareness of their importance is still lacking. Unfortunately, they are still too often filled in or drained without recognizing their value.

Agnieszka Hobot: What about the impact of wetlands on climate? You mentioned carbon storage, but also that wetland drainage contributes to gas emissions. How does this process work?

Mariusz Lamentowicz: This is a crucial issue. Wetlands, particularly peatlands, play a major role in the global carbon balance. Wetland vegetation—especially in peat bogs—absorbs carbon dioxide from the atmosphere during photosynthesis and stores it in its biomass. Under normal conditions, when the water level is high enough, dead organic matter (such as roots, leaves, stems, and mosses) does not fully decompose because water blocks oxygen flow. As a result, peatlands become massive carbon reservoirs, capable of storing it for thousands or even millions of years.

The problem arises when drainage begins, for example, through land reclamation or river regulation. When the water level drops below 20 cm, oxygen starts penetrating the peat, and microorganisms—especially fungi—accelerate its decomposition. The effect? The peat essentially starts to burn through oxidation, releasing carbon that had been stored for millennia into the atmosphere as carbon dioxide. This not only accelerates climate change but also degrades the peatlands themselves, reducing their area and destroying unique ecosystems.

Interestingly, the same thing happens in areas where water levels drop not due to human activity but because of climate change. A good example is Siberia—until recently, snow covered it with a thick layer in winter, and melting in spring replenished the wetlands. However, there is now less snowfall, and water evaporates faster, causing the peatlands to dry out. As a result, organic matter starts to break down, releasing carbon into the atmosphere. This is a global phenomenon that further accelerates warming.

Agnieszka Hobot: What is the situation like in Poland? Do we still have any wild, natural wetlands? Which do you consider the most valuable?

Mariusz Lamentowicz: Compared to the rest of Europe, Poland still has relatively well-preserved wetlands, although their condition varies by region. In Western Europe, many wetlands have been completely drained, but we still have some impressive ecosystems.

The most valuable ones are those that have not been significantly altered by human activity. In Poland, the number one wetland is undoubtedly the Biebrza Valley. It is one of the largest and best-preserved peat bog complexes in Europe—an absolutely unique area in terms of nature and ecosystem diversity. The Rospuda Valley, although smaller, is also extremely valuable.

Northern Poland is also rich in peatlands, especially those formed after the retreat of glaciers. In the Bytów area, there are small but numerous kettle-hole bogs—tiny, several-hectare wetlands formed by the melting of dead ice blocks. Their sheer number is impressive—if we combined their total area, they would form a vast wetland complex.

In western Poland, the Noteć Valley is particularly valuable, as it is largely composed of peat bogs. We must also mention the Warta River Mouth National Park, which is one of the most important breeding sites for wetland birds in Europe.

Especially significant are Kusowo Bog near Szczecinek, one of the best-preserved Baltic-type raised bogs in Poland, and the Orawsko-Nowotarskie Peatlands in Podhale, the largest complex of this type in the Polish Carpathians.

Overall, peatlands cover about 4 percent of Poland’s territory. While this may not seem like a large number, in terms of carbon storage, they surpass forests. It is estimated that they contain over 2 billion tons of organic carbon, while all the trees in Polish forests combined hold less than 1 billion tons.

Ultimately, it is not just about their size but the functions they serve. Wetlands store water, filter it, regulate the climate, and provide a habitat for unique biodiversity.

main photo: Dorina Perry / Unsplash