1. Univ. of Hohenheim, Inst. of Soil Science and Land Evaluation; Biogeophysics Section; D-70599 Stuttgart Germany
2. EHWM CU/CMU; Chiang Mai Univ.; 50200 Chiang Mai Thailand
3. Chiang Mai Univ.; Faculty of Agriculture; 50200 Chiang Mai Thailand
4. Chiang Mai Univ.; Faculty of Science; 50200 Chiang Mai Thailand