1. Dep. of Agroecology Faculty of Science and Technology; Aarhus Univ.; Blichers Allé 20 P.O. Box 50 DK-8830 Tjele Denmark
2. Ecoinformatics and Biodiversity Group Dep. of Bioscience; Aarhus Univ.; Ny Munkegade 114 DK-8000 Aarhus C Denmark
3. Dep. of Environmental Sciences Faculty of Agriculture and Environment; The Univ. of Sydney; Biomedical Building C81 1 Central Avenue Eveleigh NSW 2015 Australia