Degraded Peatlands Emit Nearly Twice As Much Greenhouse Gas As Previously Thought

For the first time, researchers have produced a detailed, high-resolution map of peatlands in the EU, showing that these areas emit twice as much greenhouse gases than previously thought. The research, led by eco-hydrologist Quint van Giersbergen of Radboud University, has been published in Nature Communications.

The extent to which drained peatlands emit greenhouse gases is often underestimated. Globally, these landscapes account for 5% of all emissions. Van Giersbergen explains: ‘In the European Union, 6% of all land consists of peatlands. Half of these areas have been drained and are used for agriculture and forestry.’ This is problematic, because undrained peatlands store large amounts of carbon when dead plants are not fully decomposed. ‘When these peatlands are drained, not only harmful carbon is released, but nitrogen is also emitted in the form of nitrous oxide.’

Inaccurate reporting
Accurate reporting of peatland emissions is therefore crucial. And that is where the problem lies, says the eco-hydrologist: ‘Countries often underestimate emissions because, for example, land use and surface areas are not fully accounted for, or the correct gases are not included. The Netherlands, for instance, reports unexpectedly low emissions from peat ditches.’ This reporting falls short and it was also unclear where emissions were highest.

Hotspots in the Netherlands
Van Giersbergen and his team therefore created a detailed map of peatland emissions across Europe. They collected up-to-date data and used a supercomputer to convert it into a comprehensive map. ‘We found that emissions from peatlands were almost twice as high as what European countries currently report. This is mainly due to systematic underestimation.’ The data also revealed that emissions are not evenly distributed. ’17 percent of peatlands account for 39 percent of emissions', says the researcher. ‘The largest hotspots are located in the area around the northeast of the Netherlands and northwest Germany. Regions in England, the Baltic states, Poland, and Ireland also show relatively high emission levels.’

The solution is already there: previous research by Radboud University and others shows that rewetting peatlands is an effective way to reduce greenhouse gas emissions and restore peatland biodiversity. Agriculture and forestry do not necessarily have to stop on rewetted peat; certain plant species that can be used, for example, as insulation material grow very well in wet conditions. Van Giersbergen emphasizes: ‘I believe it is crucial that the EU immediately begins rewetting the hotspots—something that must happen anyway under the Paris Agreement.’ By identifying where reductions can be achieved most efficiently, this study provides the evidence needed to accelerate climate-smart land-use decisions across the EU.

This research was conducted in collaboration with the University of Greifswald, the Greifswald Moor Centre, and the Finnish LUKE Institute.