A meadow on the outskirts of Greifswald: Cattle graze here in summer, the ground is a striking dark brown color. If you don’t know, you won’t notice that one of the many moors of Mecklenburg-Western Pomerania was here. Of the 1.8 million hectares of heathland in Germany, 98% is drained. Much of it is now used in agriculture.
“So the meat is mainly produced in these areas,” explains agricultural engineer Wendelin Wichtmann. “This means that every kilogram of meat is purchased with high greenhouse gas emissions, which can no longer be justified in the long term.” Wichtmann studies the rewetting of heathland at the Greifswald Moor Center.
Agriculture in the bog
More than a third of CO2 emissions from agriculture escape from drained peat soils, even if these represent less than 10% of the surface used. According to Wichtmann, rewetting is essential to meeting the Paris climate goals. But farmers face a problem. “Corn in a wet bog does not work.”
That is why the Greifswald Moor Center strives to offer an alternative to farmers. “If you re-wet the bogs, you can leave them to their own devices – or you can keep farming them.” And this is where malaria comes in. “This means that water levels are set in a way that allows for the greatest possible reduction in greenhouse gases, while allowing cultivation.” Malaria – this means the agricultural cultivation of wetlands. In short: agriculture in the moor.
Cattails as an insulating material
Josephine Neubert leads a project at the Greifswalder Moor Centrum studying the cultivation of cattails. In the summer of 2019, his team used a lot of machinery to wet an eight-hectare area on the Teterower Peene. “In 2019 we were lucky enough to separate a piece of land from a farmer’s polder near Neukalen, which we were allowed to redesign and rewet.”
Neubert shows photos of the project. “And we filled in a ditch, dug new ditches and created it here in the drained landscape like an island.” With 80,000 cubic meters of water. Next, cattail plants were planted. After 1.5 years of growth, the first harvest was expected this winter.
Harvesting in reedbeds: The management of moors is still in an experimental phase.© Nora Köhn
Insulation boards for house construction can be pressed from cattails. “The leaves have air chambers inside which provide thermal insulation. We have a plant that is very stable and quite light, but has strong air chambers and is therefore ideal as a building material,” explains Neubert.Rushes can also be used for insulation when chopped.An ecological building material whose cultivation preserves the peat body of the moor and thus protects the climate.
Water level is crucial
However, its cultivation is still in the testing phase. “The issues we’re having now with other plants that we don’t really want are due to the fact that we had issues adjusting the water level properly the first year.” Instead of fertilizers and pesticides, water level regulation is central in the moor. Gaining experience here is one of the goals of the project.
In addition to cattails, reeds and wet meadow grasses can be grown in the bog, both of which can be used as insulation material or burned in heating plants to produce energy. Peat moss grows in raised bogs and could replace conventional peat in horticulture. Water buffalo and black alder also provide an opportunity to gain economic benefit from the bog.
A house made of bog materials
But all of these products are currently facing the same problem, says agricultural engineer Wichtmann: “We have a bit of a chicken-and-egg problem. Let’s first produce a lot of biomass in the wet moors and then see how the biomass can be used. It does not work. The purchase side must develop together with the production side.
With malaria, a new branch of the economy is to develop in Germany. Torsten Galke is one of the people working there. In an airy room on the outskirts of Greifswald, he works on solutions with his company “Moor and more”.
This small house was also built with materials from the moor.© Deutschlandradio / Isabell Röder
In cooperation with the Greifswalder Moor Centrum, he built a small house with as many materials from the moor as possible. “We worked very rough here with reeds, cattails, alder and wet prairie grasses,” he says. “Here we have an insulating mat. Looks like an ordinary insulating mat, as is also known for rock wool. It’s not a pure wet meadow product, but it works too.
The reed is imported to Germany
Galke drives through the transportable house the size of a construction container. He points to the cupboards, assembled from reddish and black panels. The house diamond, as he calls it. “The panels are made only of grass, grass of the wet meadows in this case with reeds. There is no binder in them, they only bind because of the fraying that is made of them. He hopes to be able to market this method soon.
At present, the plates are still made by hand, a very laborious process. “You can create one or two of these slabs, each about a square meter, per day. We are in the process of automating this and hope that next year we will be ready to set up our first pilot plant here near Greifswald.
Heath products should not be niche products. If the price is right, there will be interest, Galke is sure. In fact: to date, Germany has imported around three quarters of the reed processed here from China, Ukraine and Romania.
EU agricultural subsidies for cattails and reeds
Something seems to be changing politically. So far, cattail and reed farmers have not received direct EU agricultural subsidies. That could soon change. Federal states such as Brandenburg have now launched programs that provide financial support for the waterlogging of large areas.
Large-scale waterlogging – this is an urgent need for pioneers like Torsten Galke. “We’ve been talking about it for a long time,” he says. Only the last step is missing. “Just do it. So that we can wet the moors to meet the Paris climate protection targets. So that we can finally stop the fact that so much CO2 comes out of these areas.”