Jen-How Huang, University of Basel, Basel, Switzerland, Stefan Osterwlalder, Louisville, CO, United States, Katrin Meusburger, Zürcherstrasse 111, Birmensdorf, Switzerland, Jorg Rinklebe, University of Wuppertal, Wuppertal, Germany, Xinbin Feng, GIG Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, China and Christine Alewell, University of Basel, Environmental Geosciences, Basel, Switzerland