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Harvests from rewetted land

To reduce greenhouse gas emissions we need to restore huge areas of degraded peatland. Paludiculture can play an important part in stimulating interest among landowners.

One approach when restoring drained peatlands is to “rewet and forget”. Another is to restore the water level but still find ways to use the land for production. Paludiculture is the fancier term for the latter. It is more precisely defined as “the productive use of wet and rewetted peatlands that preserves the peat soil and thereby minimises CO2 emissions and subsidence”.

And the restoration of peatlands needs to accelerate, as it has been identified as a cost-effective mitigation measure. Within the European Union, the large-scale drainage and overexploitation of peatlands accounts for roughly 5 per cent of total greenhouse gas emissions. On the other hand, peatlands – if untouched, restored or sustainably maintained – can act as important carbon sinks. The European Union could reduce up to 25 per cent of greenhouse gas emissions from agriculture and agricultural land-use by rewetting just 3 per cent of the land (see figure).1

Paludiculture can be done in numerous ways. Releasing livestock to graze or to harvest fodder might be one of the most straightforward forms of paludiculture (see case study). It has also been practised since ancient times, but less so in the last couple of decades as more and more peatlands have been drained and animal husbandry has become more efficient.

Another traditional type of paludiculture is harvesting reeds and using them as building materials, mainly for roofing. As interest grows in building conservation and traditional techniques, there is an increased, and in some places even unsatisfied, demand for reeds for rooftops.

Paludiculture can also provide more innovative products. One example from Germany is boards made from reeds that can be used to construct interior walls and furniture, much in the same way as chipboard. Another example comes from a project in Estonia, where they harvest the sphagnum mosses that form the top layer of a bog and use it as a growing medium in horticulture.

However, the sustainability of paludiculture has also been disputed. When compared to completely untouched peatlands, paludiculture is a worse alternative in terms of carbon storage and biodiversity. Instead, it should be seen as an alternative to business-as-usual farming on drained land. The benefits of an individual restoration project then depend on the initial greenhouse gas emissions, the choice of plant species and the water table level.

So far paludiculture is just a niche activity in the European Union. Although there are several ways for member states to support paludiculture under the CAP, according to a report from EEB and BirdLife Europe2 few member states have done so in practice. The report assessed Strategic Plans in seven northern member states. It found that some member states have eco-schemes and Pillar 2 measures that support the management of remaining wetlands. But there are no schemes that aim to incentivise broad-scale rewetting.

More promising is the proposed Nature Restoration Law (NRL) that sets national targets for peatland restoration. It also recognises paludiculture as a possible alternative land use. Unfortunately, the proposal does not include drained peatlands covered by forest, which constitutes much of the area in need of rewetting in the northernmost member states.

The newly launched Carbon Removal Certification Framework is another Commission proposal that might be of significant use for the uptake of paludiculture. There is, of course, much to be said about voluntary carbon credits, whose intended buyers are large food companies that want to be able to claim climate neutrality in their marketing. There are many of us who would prefer an ambitious programme under the CAP. But credits that would incentivise rewetting and the spread of paludiculture are among the more reasonable aspects of the proposal.

Kajsa Pira

1 Opportunities for Paludiculture in the CAP https://europe.wetlands.org/news/opportunities-for-paludiculture-in-the-...
2 Peatlands and wetlands in thenew CAP: too little action to protect and restore https://www.birdlife.org/wp-content/uploads/2022/04/Analysis-Peatlands-W...

Case study: 6 ha rewetted grassland saves 100 tonnes CO2 a year

To learn more about how paludiculture works in practice, I met with Nerijus Zableckis, director at the Foundation for Peatland Restoration and Conservation, a Lithuanian NGO. He describes paludiculture “as an opportunity for landowners to continue to get a return on their land even after it has been restored”. His organisation offers trainings to landowners and land managers. Improving the state of knowledge is a first step, “you see, most people haven’t made the connection between peatlands and climate change”.

In Lithuania, emissions from degraded peatlands are a big deal, as they account for around 10 per cent of Lithuania’s total greenhouse gas emissions and 40 per cent of the emissions from the agricultural sector.

The organisation’s first paludiculture project was carried out in 2021 on six hectares of grassland in central Lithuania, managed by the Lithuanian Veterinary Academy. At the start of the project, the land was classified as highly degraded peatland. Like much farmland, it was originally wetland that was drained in the first half of the 20th century. Drainage pipes had been buried and led the water out into a ditch. So when the decision was taken to rewet the area it could be done easily by damming the ditch.

In the area closest to the ditch there is a strip that will be constantly under water. Plants that can withstand constant wetness, such as cattail, sedges and reeds, were planted here. However, most of the area is only flooded for parts of the year and dries up during the summer. This area could remain grassland and here it is possible to let livestock graze or harvest hay for fodder and bedding.

The project included calculating the prevented greenhouse gas emissions. Nerijus Zableckis is happy with the results. This relatively small project was estimated to mitigate 100 tonnes of CO2 emissions each year until 2050. What might this mean if the project were upscaled, bearing in mind that Lithuania alone has 250,000 ha of drained peatlands used for farming? Unfortunately, it is not just a matter of multiplication, as the level of carbon dioxide emissions from peatlands varies greatly. But even conservative calculations show great potential.

Figure. Relation between share of peatlands used for agriculture in the EU and selected member states and the attributed share of greenhouse gas emissions from these areas.  Rewetting just X% of agricultural land will reduce agricultural greenhouse gas emissions by up to Y%.

 

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