Ci-Jian Yang, National Taiwan University, Department of Geography, Taipei, Taiwan, Jens Martin Turowski, Helmholtz Centre, German Research Centre for Geosciences (GFZ), Potsdam, Germany, J C Lin, National Taiwan University, Taipei, Taiwan, Chia-Hung Jen, National Kaohsiung Normal University, Kaohsiung, Taiwan and Chun-Wei Tseng, Taiwan Forestry Research Institute, R. O. C. (Taiwan), Taipei, Taiwan