Hans Joosten | Institute of Botany and Landscape Ecology, Ernst-Moritz-Arndt University, Greifswald
Abstract: Peat (organic) soils cover only 3% of the land but hold more carbon than all global forest biomass. 5% of these soils (= 0.4% of the land) has been drained, mainly for cropland, grazing land, and forestry. As a result they emit 5% of the total global anthropogenic greenhouse gases (GHG). Most (>95%) peat emissions are caused by only 25 UNFCCC parties (incl. the EU).
A substantial emission reduction can be achieved by rewetting drained peat soils. Rewetting also stops soil degradation, subsidence, salt intrusion, and consequent loss of productive land, and improves water purification, meso-climate, flood control, and biodiversity.
Many countries can kick-start national emission reductions by focussing on drained peat soils. In 25 countries (18 developing and 7 European Annex-I countries), emissions from drained peat exceed 50% of the total emissions from fossil fuels and cement. In an additional 25 countries, emissions exceed 10% of those from fossil fuels and cement.
In Germany, organic soils used for agriculture comprise 7.3% of the agricultural land, but emit more than one third of all emissions from agriculture, including those from enteric fermentation and fertilization. Rewetting organic soils thus concerns a minor part of total agricultural land only Reaching similar emission reductions in fertilization and animal husbandry will much stronger affect agricultural productivity. Furthermore, rewetting does not imply discontinuation of agricultural use. Paludiculture, the productive use of wet peatlands, provides ample opportunities to continue production while avoiding the environmental burden of drainage based agriculture.