1. a Department of Geography , Remote Sensing Unit at the Institute of Geography, University of Wuerzburg , Am Hubland , 97074 , Wuerzburg , Germany
2. b National Commission for the Knowledge and Use of the Biodiversity (CONABIO) , Tlalpan , 14010 , Mexico D.F. , Mexico
3. c German Remote Sensing Data Centre (DFD) of the German Aerospace Center (DLR) , 82234 , Wessling , Germany
4. d Center for Development Research (ZEF), University of Bonn , 53113 , Bonn , Germany