1. Assistant Professor, Dept. of Civil Engineering, Univ. of Qom, Qom, Iran; formerly, Dept. of Irrigation and Reclamation, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, Univ. of Tehran, Karaj, 3158777871 Tehran, Iran.
2. Professor, Dept. of Irrigation and Reclamation, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, Univ. of Tehran, Karaj, 3158777871 Tehran, Iran (corresponding author).
3. Professor, Dept. of Geography, Univ. of California, Santa Barbara, CA 93016-4060.