1. Dep. of Civil Engineering Faculty of Engineering Univ. of Peradeniya Peradeniya 20400 Sri Lanka
2. Graduate School of Agricultural and Life Sciences Univ. of Tokyo Japan
3. Dep. of Geosciences and Natural Resource Management Center for Permafrost (CENPERM) Univ. of Copenhagen Øster Voldgade 10 Copenhagen DK‐1350 Denmark
4. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F Univ. Yangling Shaanxi 712100 China
5. Dep. of Soil and Physical Sciences Lincoln Univ. P.O. Box 85084 Lincoln 7647 New Zealand
6. Dep. of Civil and Environmental Engineering Southern Methodist Univ. Dallas TX 75205 USA
7. Indian Institute of Science Bangalore India