1. Institute of Geosciences; University of Potsdam; Karl-Liebknecht-Str. 24 Golm 14476 Germany
2. Department of Engineering for Crop Production; Leibniz-Institute for Agriculture Engineering Potsdam-Bornim; Max-Eyth-Allee 100 Potsdam 14469 Germany
3. Department of Plant Nutrition; Institute of Vegetable and Ornamental Crops Großbeeren/Erfurt; Theodor-Echtermeyer-Weg 1 Großbeeren 14979 Germany