Darius J. Semmens

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based model describing the processes of interception, infiltration, surface runoff, and erosion from small agricultural and urban watersheds (Smith et al., 1995). In this model, watersheds are represented by subdividing contributing areas into a cascade of one-dimensional overland flow and channel elements using topographic information. A broadly updated(More)
As human pressures on ecosystems continue to increase, research involving the effective incorporation of social values information into the context of comprehensive ecosystem services assessments is becoming more important. Including quantified, spatially explicit social value metrics in such assessments will improve the analysis of relative tradeoffs among(More)
To enter widespread use, ecosystem service assessments need to be quantifiable, replicable, credible, flexible, and affordable. With recent growth in the field of ecosystem services, a variety of decisionsupport tools has emerged to support more systematic ecosystem services assessment. Despite the growing complexity of the tool landscape, thorough reviews(More)
KINEROS (KINematic runoff and EROSion) originated in the 1960s as a distributed event-based model that conceptualizes a watershed as a cascade of overland flow model elements that flow into trapezoidal channel model elements. KINEROS was one of the first widely available watershed models that interactively coupled a finite difference approximation of the(More)
Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios aredeveloped in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the(More)
based model describing the processes of interception, infiltration, surface runoff, and erosion from small agricultural and urban watersheds (Smith et al., 1995). In this model, watersheds are represented by subdividing contributing areas into a cascade of one-dimensional overland flow and channel elements using topographic information. A broadly updated(More)
Studies of future management and policy options based on different assumptions provide a mechanism to examine possible outcomes and especially their likely benefits and consequences. The San Pedro River in Arizona and Sonora, Mexico is an area that has undergone rapid changes in land use and cover, and subsequently is facing keen environmental crises(More)
Data for biophysically modeled and Public Participatory GIS (PPGIS)-derived cultural ecosystem services have potential to identify natural resource management synergies and conflicts, but have rarely been combined. Ecosystem service hot/coldspots generated using different methods vary in their spatial extent and connectivity, with important implications. We(More)
This report represents a state-of-the-art synthesis of current knowledge of the ecology and hydrology of ephemeral (dry washes) and intermittent streams in the American Southwest, and may have important bearing on establishing nexus to traditional navigable waters (TNW) and defining connectivity relative to the Clean Water Act. Ephemeral and intermittent(More)
The Automated Geospatial Watershed Assessment (AGWA, see: www.tucson.ars.ag.gov/agwa) tool is a GIS interface jointly developed by the USDA-Agricultural Research Service, the U.S. Environmental Protection Agency, the University of Arizona, and the University of Wyoming to automate the parameterization and execution of the Soil Water Assessment Tool (SWAT)(More)