Associate Editor, Journal of Contaminant Hydrology, 1999-present.
Associate Editor in Chief, Journal of Water Science and Engineering, 2008-present.
Associate Editor, Journal of Hydrologic Engineering, 2008-present.
Associate Editor, Water Resources Research, 2003-2006.
Chair and Convenor, H11: Interactions among Hydrologic Processes, Eco-biologic Processes, and Human Activities in Watersheds, AGU Western Pacific Meeting, Beijing, July, 2006.
Guest Editor, Journal of Hydrology, the special issue of "Water and Solute in Arid Regions", 2000-2003.
Member, the review panel on the Strategic Environmental Research and Development Program (SERDP), U.S. Department of Defense (DOD), 2002.
Chair, Hydrology Session I, AZ-NV Academy of Science, Las Vegas, April, 2001.
Chair and Convenor, Studies on Transport of Water and Solute in Arid Regions, GSA Annual Meeting, Reno, November, 2000.
Member, Large-Scale Field Experimentation Committee of American Geophysical Union, 1998-present.
Guest Editor, Journal of Global and Planetary Change, the special issue of " Regional Climate - Hydrology Interactions", 1998-2000.
Member, IAH Commission for Ground Water Protection, 1998-present.
Invited Presentation. A coupled hydrologic modeling system. American Association for the Advancement of Science (AAAS) Annual Meeting and Science Innovation Exposition, Feb., 1998.
Chair, H11F and H12B - Integrated Study of Regional Climate and Hydrology in Basin-Scale Field Experiments (I, II), AGU Fall Meeting, San Francisco, Dec., 1997.
Judge, Hydrology Section Student Presentation, AGU Spring Meeting, Baltimore, 1997; San Francisco, Dec., 1997; AGU Spring Meeting, Boston, May, 1997.
Convenor, H04 - Integrated Study of Regional Climate and Hydrology in Basin-Scale Field Experiments, AGU Fall Metting, San Francisco, 1997.
Participation in workshop on Climate Change Impacts in the Mid-Atlantic Region (proposed by the Office of Science and Technology Policy), State College, September, 1997.
About 10 manuscript and proposal reviews annually besides journal editing duty.