1. Department of the Sciences of Agriculture; Food and Environment; University of Foggia; via Napoli 25 71122 Foggia Italy
2. Department of Renewable Resources; University of Alberta; 348E South Academic Building T6G 2H1 Edmonton AB, Canada
3. Department of Renewable Resources; University of Alberta; 442 Earth Sciences Building T6G 2E3 Edmonton AB, Canada
4. Institute of Geography; Dresden University of Technology; Helmholtzstr. 10 01069 Dresden Germany