Fully distributed versus semi-distributed process simulation of a highly managed watershed with mixed land use and irrigation return flow

Spatially distributed process models represent soil-water-plant-nutrient interactions within a watershed. We investigated spatial patterns of water balance components and nitrate transport simulated using the fully AgES (Agricultural Ecosystems Services) semi-distributed SWAT (Soil Water Assessment Tool, 2012) in Big Dry Creek Watershed, mixed agricultural suburban watershed semi-arid Colorado, USA. analyzed hydrological fluxes daily model outputs for period 2010–2018. The two drastically different patterns. predicted extremely low interflow routed excess irrigation to surface runoff groundwater discharge. produced realistic estimation streamflow, return flows, nitrate; simulation less greater baseflow contributed improved interior watersheds. This study demonstrated impacts simulating spatially explicit hydrology that captures among fields other areas managed