1. Department of Physical Geography and Ecosystem Science Lund University Box 117 Lund 221 00 Sweden
2. Geoecology, Department of Environmental Sciences University of Basel, Klingelbergstraße 27 Basel 4056 Switzerland
3. Center for Water Infrastructure and Sustainable Energy (W I S E), Futures, Nelson Mandela African Institution of Science & Technology PO Box 9124, Nelson Mandela Tengeru Arusha Tanzania
4. York Institute for Tropical Ecosystems, Department of the Environment and Geography University of York York YO10 5NG UK