ABSTRACT

The ongoing drought in the Southwestern United States places pressure on both scientists and practitioners to find new solutions to water-related issues. In the state of Arizona, this situation requires that the present state of the ecosystems and natural resources be re-evaluated to assess their capacity to sustain the future flow of ecosystem services to society. Ecosystem Services (ES) are the contributions of ecosystem structures and functions – in combination with other inputs – to human well-being (Burkhard et al., 2012a). The availability of water as a benefit provided to people by nature is dependent on multiple human and non-human factors. Human activities change the environment in ways that alter its structure and functioning. By using hydrological models of the system, we can develop quantitative simulations of the ways in which existing environmental conditions influence the hydrological cycle. Different elements of the hydrological cycle influence the supply of Water-Related Ecosystem Services (WRES) to society. It is, therefore, important for decision-makers to quantitatively understand how various human activities can influence the functioning of those natural processes.