Peatlands are terrestrial ecosystems that hold more carbon than any other ecosystem, despite covering only 3% of the Earth. This immense carbon storage power -- and the variety of other vital ecosystem services they offer -- highlight their importance in climate change mitigation.
Read on to learn:
Peatlands are terrestrial environments, a type of wetland with a naturally accumulated layer of organic material (peat). The definition varies between countries and no single one is globally accepted. Generally, though, peatlands are defined as having a peat thickness of at least 30cm and organic matter content of at least 65%.
Peatlands exist in a variety of climates. A recent study revealed that around 83,3% of peatlands are boreal and polar, 12,7% tropical, and 4% temperate. These combined make up a total peatland area of 463,2 million hectares (Mha). 65 Mha of these are estimated to have been affected by humans.
Recently, a vast area with peat coverage of approx. 140*103 km2 was identified in the Congo basin swamp forest. This peatland, known as Cuvette Centrale, is today the most extensive peatland complex in the tropics, storing roughly 30.6 Gt of carbon.
Peatlands are constantly water-logged, depleting the oxygen and leading to an anoxic environment. This means that dead plants cannot fully decompose and eventually accumulate as peat. All the carbon in the plants is stored within the peat, making peatlands the biggest carbon storage among all ecosystems, despite only covering 3% of Earth’s surface. This makes peatlands the ultimate nature-based solution in halting climate change.
It is mainly human activities, especially drainage, that affect peatlands and, therefore, the whole terrestrial carbon cycle. To continue to be climate superheroes, peatlands must stay water-logged and intact.
However, peatlands are:
Healthy (wet) peatlands sequester approximately 0.37 Gt of CO2 per year. However, when damaged, peatlands turn from being carbon sinks to carbon sources, releasing around 5% of all global anthropogenic CO2 emissions.
The carbon storage of one hectare of peatland is, on average, 1375 tonnes; equal to annual emissions from 1400 cars.
The draining of peatlands, in turn, leads to emissions of vast amounts of greenhouse gases that have been locked in peat for centuries. This further increases the risk of wildfires, loss of biodiversity, and more. In addition to releasing GHGs, it may take tens or even hundreds of years to restore the carbon they once stored.
In Russia, millions of hectares of peatlands have been drained over several decades. The peat fires of 2010 are associated with 50 000 deaths and 260 Mt of CO2 emissions. Not to mention that it’s not only Russia burning peatlands, but also places like Indonesia suffering from exhaustive peat fires. The Indonesian fires of 2015 are driven by the growing demand for palm oil and pulp. They’re believed to be related to 100 000 premature deaths and contribute to a mean daily CO2 emission rate of 11.3 Tg. That’s higher than the whole EU daily fossil fuel emissions. Similar events have also been happening in other parts of the world.
Urgent and more radical action is needed to rewet and restore peatlands to make them more resilient towards fires.
Peatlands are not only for storing carbon but offer many other ecosystem services that are vital to a healthy planet.
These include (but are not limited to):
Peatlands have a lot to offer. In Eurasia, the collection of berries and wild mushrooms has been an important part of the diet for some nations. Peatland waters are home to many fish species, which offer an important source of proteins. Tropical peat swamp forests provide many edible fruits and plants that are vital to the well-being and livelihood of local indigenous communities.
A recent study estimated that 71.4 million people globally depend on peatland for water. This is most important in the UK and Ireland, where 85% of drinking water is sourced from peatlands.
Peatlands are also of global significance for biodiversity, with many peatland species and habitats rare, threatened, or declining. Although peatlands have quite poor wildlife (species-wise), many of the species are peatland specialists.
Unique assemblages of species can be found in peatland habitats. Just to name a few:
Furthermore, peatlands preserve the past, like an archive, holding a good record of past biodiversity, condensed in the layers of peat, revealing the history as the research advances through pollen records and human artifacts.
However, failing to fully consider the economic value of biodiversity and ecosystem services - including their potential to mitigate climate change - is driving the continuous loss and degradation of those valuable ecosystems.
All is not lost. There are several methods for helping peatlands to thrive.
First and foremost, there has been an advanced understanding of the value peatlands create and the services they provide. It is recommended that intact peatlands should be protected and kept wet. The ones that have been drained should be rewetted. Restoration of tropical peatlands alone could reduce GHG emissions annually by 800 million tonnes; equal to 3% of global emissions.
Fortunately, much effort is being put into rewetting and restoring peatlands. Some examples include the WaterLANDS project and the Scotland government's action. An Europe-wide WaterLANDS project will contribute to the restoration of 10,500 hectares of wetlands, previously damaged by human activity. The project started at the end of 2021 and will run for 5 years, with funding allocated from H2020 Green Deal Call 7.1. Furthermore, the Government of Scotland has announced plans to restore 250,000 hectares of peatlands by 2030. Many other successful restoration projects globally have been carried through or are planned in the near future, with a significant effect on the avoided GHG emissions.
Paludiculture is also an emerging field of research that focuses on rewetting drained peatlands and using the wet soil for agricultural production: producing crops, cultivating reed, and farming Sphagnum. This keeps the peatlands as carbon storage while utilizing them as farmable land and it should be carbon-negative or carbon-neutral in the long term. There is a great movie about carbon farming made in collaboration with several organizations, including IUCN Peatland Programme, the National Trust for Scotland, and Moors For The Future.
All in all, these are just a few examples of the great work being done worldwide. Sure, there is still plenty of research and investment needed to restore peatlands and sustainably manage them. Recognizing peatland’s value is just the first step. Direct financing, like Single.Earth’s MERITs could provide a solution for keeping intact peatlands untouched or restoring those that have been damaged.