Water covers most of our planet's surface, but it comes in the form of salty ocean water, not fresh and usable water for human consumption.

Many residents in Arizona are well aware of some of these challenges, and a growing number of their neighbors to the south, in the Mexican state of Sonora, are also paying increasing attention to these issues as part of cooperative programs.

Christopher Scott, Ph.D., is an associate professor at the University of Arizona, and he is taking part in cross-border efforts to protect rivers, such as the San Pedro and the Santa Cruz Rivers.

Scott is involved with a variety of organizations, including Udall Center for Studies in Public Policy, the UA's School of Geography and Development, AQUASEC - Center of Excellence for Water Security and Water Resources and Policy Group.

Scott recently visited AZ Illustrated Nature to speak about some of his work.