1. Northern Rivers Institute, Department of Geography and Environment; School of Geosciences, University of Aberdeen; AB24 3UF Aberdeen Scotland UK
2. Fluvial Dynamics Research Group, Department of Environment and Soil Sciences; University of Lleida; E-25198 Lleida Catalonia Spain
3. Forest Science Centre of Catalonia; E-25280 Sant Llorenç de Morunys, Solsona Catalonia Spain
4. Institute of Geography and Earth Sciences; Aberystwyth University; SY23 3DB Aberystwyth Wales UK
5. Catalan Institute for Water Research; H 2 O Building E-17003 Girona Catalonia Spain