Organic Soil Surface Area

Peat is formed in water-governed, low-oxygen conditions in raised bogs (as found at the Etang de la Gruère in this image) and many fens.
© ETH-Bibliothek Zürich, Bildarchiv / Fotograf: Gautschi, Hans-Peter

To estimate the emissions of organic soils we need to know their areal extent and how they are managed. A reference map of the extent of current organic soils was created by compiling evidence of the existence of organic soils from soil maps, habitat maps, bog inventories and historic maps and texts. The remaining organic-soil surface is estimated at around 28,000 ha, approx. three-quarters of which is used for forestry or agriculture. 

orgBoden map
The surface of Switzerland’s organic soils according to Wüst-Galley et al., 2015;
Hillshade and lakes © Swisstopo

This map is used to calculate the emissions of organic soils for the Swiss Greenhouse Gas Inventory. This map needs to be updated, since the continual mapping of habitats and soils provides new information on the extent of organic soils.

Carbon stocks in Switzerland’s organic soils are estimated at around 32.4 million tonnes. This figure is, however, associated with (unknown) uncertainties, as it was calculated using the information on area, peat-layer thickness and carbon density, which are themselves estimated values.

In Switzerland, the majority of organic soils are managed for agricultural or forestry