SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Simulation of a low-gradient coastal plain watershed using the SWAT landscape model 
Authors:Bosch, D.D., J.G. Arnold, M. Volk and P.M. Allen 
Journal:Transactions of the ASABE 
Article ID: 
URL (non-DOI journals):http://ddr.nal.usda.gov/handle/10113/46736 
Broad Application Category:hydrologic only 
Primary Application Category:hydrologic assessment 
Secondary Application Category:none 
Watershed Description:.84 ha Gibbs Farm Fox Den Field study site near Tifton, Georgia, USA 
Calibration Summary: 
Validation Summary: 
General Comments: 
Abstract:Accurate simulation of landscape processes in natural resource models requires spatial distribution of basin hydrology and transport processes. To better represent these processes, a landscape version of the SWAT model has been developed to simulate the runoff, run‐on, and infiltration processes that typically occur in different parts of the landscape. The model addresses flow and transport across hydrologic response units prior to concentration in streams, and is capable of simulating flow and transport from higher landscape positions to lower positions. The SWAT landscape model was tested using data collected from a heavily vegetated riparian buffer system in the Atlantic Coastal Plain near Tifton, Georgia. Simulations of surface runoff, lateral subsurface runoff, and groundwater flow for an upland field, a grass buffer, and a sub‐divided forested buffer floodplain were generated. Model results and field data indicate that surface runoff was dominant in the upland field, while groundwater flow was dominant in the grass buffer and the floodplain. While average annual surface runoff agreed satisfactorily with observations from the site, annual and monthly simulated values varied considerably from observed values. Simulated surface runoff tracked general trends in the observed data, but winter months and extreme events were overestimated while summer months were underestimated. Annual surface runoff predictions at the edge of the upland field varied from the observed data by 11% to 44%. The Nash‐Sutcliffe efficiency for annual estimates of surface runoff at the field edge was 0.83 for the three‐year calibration period. The results demonstrate the ability of the model to simulate the surface runoff and enhanced infiltration typically associated with riparian buffer systems. Additional revision of the model will likely be necessary to adequately represent redistribution of water between surface, lateral subsurface flow, and groundwater flow. 
Keywords:Natural resource modeling, Surface hydrology, Watershed modeling