While issues regarding this kind of issues as population growth, point source pollution, soil degradation, food supply, and energy may have eased in the last years with lots of positive trends, fundamental problems still exist. A few other water-related issues, particularly those concerned with water supply, non-point source pollution, and surface and groundwater quality impairment remain of great concern locally and globally Solving these water resource problems will require an improved understanding of the fundamental physical, biological, economic, and social processes, and a better knowledge of how all of these components operate together within watersheds.