1. Earth Sciences Department, University of Siena, Via Laterina, 8, 53100 Siena, Italy
2. CRA‐Research Institute for Soil Study and Conservation, Piazza M. D'Azeglio, 30, 50121 Florence, Italy
3. Environmental Sciences Department, University of Siena, Via Laterina, 10, 53100 Siena, Italy
4. Department of Geography, University of Cologne; Albertus‐Magnus Platz, 50923 Cologne, Germany
5. Institute of Soil Science and Land Evaluation, Hohenheim University, Emil‐Wolff‐Str. 27, 70599 Stuttgart, Germany