[1] Justus Liebig Univ Giessen, Inst Landscape Ecol & Resources Management ILR, Giessen, Germany
[2] Justus Liebig Univ Giessen, Ctr Int Dev & Environm Res ZEU, Giessen, Germany
[3] Ctr Int Forestry Res CIFOR, Nairobi, Kenya
[4] Univ Kabianga, Dept Agroforestry & Rural Dev, Kericho, Kenya
[5] Univ Lancaster, Lancaster Environm Ctr, Lancaster, England