Link zu WSL Hauptseite Swiss Federal Institute for Forest, Snow and Landscape Research WSL


Publication (in German)

Eidg. Forschungsanstalt für Wald, Schnee und Landschaft WSL (Hrsg.) 2013:

Bodenschutz im Wald: Ziele - Konflikte - Umsetzung. Forum für Wissen 2013.

WSL Ber. 6: 116 S.

Articles on

Soil protection

Soils fulfill various functions. They are habitats of plants, animals, microorganisms and fungi and are consequently an important basic resource for human beings. Soils govern the percolation of water and dissolved substances by acting as a reservoir, a buffer and/or a filter and therefore, they are an important regulator in element cycling. As a consequence of land cultivation and of the emission of harmful substances from various sources, the soil functions are endangered. In the research topic “soil protection” the main threats and their effects on the soil functions and hence on soil fertility are investigated.

Soil functions and soil pressures

Bodenschutz Schulung
Fig. 1: Training in physical protection
of soils in cooperation with the cantons.
Photo: Marco Walser (WSL)
Fig. 2: Tracks of a heavy forestry
vehicle on a skidder trail after repeated
vehicle crossings.
Photo: Marco Walser (WSL)

In the Swiss legislation on environment protection, soil protection is defined as the maintenance of soil fertility. Referred to the forest this means that the self-preservation of a site-specific forest-biocoenosis with a natural regeneration should be sustainably guaranteed. Root-growth of the trees may only be hindered by natural barriers and the activity of the soil biota has to enable the uninhibited decay of the plant litter under the prevalent site conditions. The main threats which endanger the above defined soil fertiltiy in forests and which are investigated in the research topic soil protection are soil compactions by heavy forest harvesters, soil contaminations with harmful substances, climat change and its influence on soil organic matter as well as alterations of the soil due to land use change.
Current and future research activities include field and laboratory investigations on the impacts of forest-harvesters on soil properties and functions and its regeneration, on the mapping of risk assessment with regard to erosion and landslides, on the assessment of ecological risks (e.g. floodwaters), on the interrelation of soil pore space and distribution of tree roots, on the interrelationship between land use change (e.g. afforestation, litter removal, application of wood ash) and soil chemical properties, and on the investigation of the gas exchange between the soil and the atmosphere depending on the degree of compaction. In addition, extention and maintenance of the data base of soil chemical and physical properties serve as an important tool in order to deduce indicators of soil health, pedotransfer functions and ecological standards for the validation of forest soils.

Bodenkarte Ermatingen Versuch mit Holzasche auf Waldboden
Fig. 3: Mapping of various types of tracks (different soil deformation) and of the risk of compaction as a basis for the operational strategy of the forest vehicles.
Graph: Peter Lüscher / Stéphane Sciacca (WSL)
Fig. 4: Small experimental plot with wood ash application to study the impacts on soil biology (corresponds to 8t wood ash per ha).
Photo: Stephan Zimmermann (WSL)