1. Department of Environmental Systems Science, ETH Zürich, CHN G 73.1; Universitätstrasse 16; CH-8092 Zürich Switzerland
2. Center for Regional System Analysis, Planning and Development; Bogor Agricultural University; Jalan Raya Pajajaran Baranangsiang Bogor 16153 Indonesia
3. Center for International Forestry Research; Jalan CIFOR; Situ Gede Bogor Barat 16115 Indonesia