1. Dept. of Irrigation and Reclamation Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, Univ. of Tehran, Karaj, 1193653471 Tehran, Iran.
2. Associate Professor, Dept. of Irrigation and Reclamation Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, Univ. of Tehran, Karaj, 1193653471 Tehran, Iran (corresponding author).
3. Professor, Dept. of Geography, Univ. of California, Santa Barbara, CA 3106.