Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1002/hyp.10197
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Title (Primary) Development of a grid-based version of the SWAT landscape model
Author Rathjens, H.; Oppelt, N.; Bosch, D.D.; Arnold, J.G.; Volk, M.
Journal Hydrological Processes
Year 2015
Department CLE
Volume 29
Issue 6
Page From 900
Page To 914
Language englisch
Keywords raster-based simulation; watershed modeling; discretization scheme; SWATgrid; landscape routing
UFZ wide themes RU1
Abstract Integrated river basin models should provide a spatially distributed representation of basin hydrology and transport processes to allow for spatially implementing specific management and conservation measures. To accomplish this, the Soil and Water Assessment Tool (SWAT) was modified by integrating a landscape routing model to simulate water flow across discretized routing units. This paper presents a grid-based version of the SWAT landscape model that has been developed to enhance the spatial representation of hydrology and transport processes. The modified model uses a new flow separation index that considers topographic features and soil properties to capture channel and landscape flow processes related to specific landscape positions. The resulting model is spatially fully distributed and includes surface, lateral and groundwater fluxes in each grid cell of the watershed. Furthermore, it more closely represents the spatially heterogeneous distributed flow and transport processes in a watershed. The model was calibrated and validated for the Little River Watershed (LRW) near Tifton, Georgia (USA). Water balance simulations as well as the spatial distribution of surface runoff, subsurface flow and evapotranspiration are examined. Model results indicate that groundwater flow is the dominant landscape process in the LRW. Results are promising, and satisfactory output was obtained with the presented grid-based SWAT landscape model. Nash–Sutcliffe model efficiencies for daily stream flow were 0.59 and 0.63 for calibration and validation periods, and the model reasonably simulates the impact of the landscape position on surface runoff, subsurface flow and evapotranspiration. Additional revision of the model will likely be necessary to adequately represent temporal variations of transport and flow processes in a watershed.
Persistent UFZ Identifier
Rathjens, H., Oppelt, N., Bosch, D.D., Arnold, J.G., Volk, M. (2015):
Development of a grid-based version of the SWAT landscape model
Hydrol. Process. 29 (6), 900 - 914