Soil erosion: quantification by aerial photography in Switzerland

Authors
Prof. Christine Alewell and Prof. Volker Roth
University of Basel

Plants, animals, and also humans live on and from the soil. However, soils are also under significant threat. The greatest spatial threat is soil erosion. Even in areas such as the Alps unstable soils are often found threatened by soil erosion. The ‘weObserve’ project therefore developed efficient strategies enabling data analyses and evaluations on a large scale and over long periods of time.

The ‘weObserve’ project has shown that soil erosion in the Swiss Alps has increased in recent years. A study has been conducted in the Urseren valley, a high-alpine valley located between the well-known Oberalp, Furka and Gotthard passes, in which aerial photographs from the period between 2000 and 2016 have been analysed. Based on this the project was able to ascertain that the area covered by degraded soil increased from around 15 to approximately 40 hectares. This means that the area has more than doubled in just 16 years. In addition to the study in the Urseren valley, the method was successfully applied in ten hillside-grassland-sites across Switzerland. The accuracy of the results can be further increased by taking particular conditions of different areas into consideration.

Second case studyon the mass migration of birds

The case study on soil erosion was not the only one in the “weObserve” project. A second case study focused on the mass migration of birds. Existing sensor data was merged with field observations to better understand the behaviour of migratory birds.

Project team

  • Prof. Christine Alewell
    Departement of Environmental Sciences, University of Basel
  • Dr Lauren Zweifel
    Departement of Environmental Sciences, University of Basel
  • Prof. Volker Roth
    Departement of Mathematics and Computer Science, University of Basel
  • Maxim Samarin
    Departement of Mathematics and Computer Science, University of Basel
  • Prof. Heiko Schuldt
    Departement of Mathematics and Computer Science, University of Basel
  • Fabricio Arend Torres
    Departement of Mathematics and Computer Science, University of Basel
  • Dr Katrin Meusburger
    Swiss Federal Institute for Forest, Snow and Landscape Research WSL

Collaboration for the sub-project “Bird Migration”

  • Dr Felix Liechti
    Swiss Ornithological Institute

About the project

Related links