The Volkswagen Foundation is supporting this workshop in the framework of the "Freigeist" – Fellowship rewarded to Dr. Matthias Beyer (Institute for Geoecology, TU Braunschweig, Germany) for his project Isodrones – Resolving the mystery of deep roots. The workshop is further sponsored by Picarro, Edaphic Scientific, and U-Series. We kindly thank them for their support!