Half of the world’s wetland area is composed of peat (or organic) soil, made up of partly decayed vegetation that is slowly accumulating instead of mineralizing, due to specific wet hydrological and climatic conditions. Such peatlands occur in almost all countries, the largest of them in the Boreal and Arctic zone in Alaska, Canada, Scandinavia and Siberia, and substantial extents also in the Tropics in Indonesia, Malaysia, the Congo and Amazon river basins. This is where the most substantial amounts of terrestrial carbon are stored and slowly accumulating since millennia – and where this carbon should remain stored safely in the peat soils.
However, about 14% (536,300 km2) of these peatlands were drained for agricultural and forestry uses. Draining peatlands triggers the oxidation of their soil carbon and its release as CO2 into the atmosphere, and it contributes to soil degradation and subsidence, salt intrusion in coastal areas and loss of productive land. Drained peatlands cover 0.4% of the world’s terrestrial surface, but they contribute 5% of all anthropogenic greenhouse gas emissions on Earth. And during dry seasons they are prone to peat fires which release added CO2 into the atmosphere through their smoke cones responsible for wide-spread human health problems.
But there is good news: solutions to overcome these problems exist - and they were addressed by about 200 specialists attending the second international conference on “Renewable Resources from Wet and Rewetted Peatlands”, organised and hosted by the Greifswald Mire Centre on 26-28 September 2017 in Germany. The specialists claim that drained peatlands need to be rewetted, and could be wisely used for “paludiculture” – a term that subsumes the sustainable production of fodder, biofuels, substrates, building materials, food, drugs and cosmetics under wet conditions. Paludiculture is a means to stop soil degradation and to diminish greenhouse gas emissions. Paludiculture as a form of wetland wise use with traditional and innovative methods in accordance with the principles promoted by the Ramsar Convention. Sustainable use of peatlands with paludiculture methods supports economies and local livelihoods and can enhance ecosystem services such as water storage, flood control, biodiversity conservation and nutrient retention.
Rewetting peatlands would have particularly significant effects in those countries, who together account for 80% of all greenhouse gas emissions from drained peatlands: Indonesia, the European Union, Russian Federation, China, Mongolia, Papua New Guinea, Malaysia and Belarus. In these countries, rewetting drained peatlands could contribute significantly to Nationally Determined Contributions to achieve the objectives of the Paris Agreement. With a view to contribute to the discussions and negotiations at COP23 of the UN Framework Convention on Climate Change in November 2017 in Bonn, the participants in the Greifswald conference adopted the statement that “Peatlands must be wet: for the climate, for the people, for the future” (attached) for the implementation of paludiculture as a form of wise use of rewetted peatlands.