Title: | Regionalization of SWAT model parameters for use in ungauged watersheds |
Authors: | Gitau, M.W. and I. Chaubey |
Year: | 2010 |
Journal: | Water |
Volume (Issue): | 2(4) |
Pages: | 849-871 |
Article ID: | |
DOI: | 10.3390/w2040849 |
URL (non-DOI journals): | |
Model: | SWAT |
Broad Application Category: | hydrologic only |
Primary Application Category: | regionalization of input parameters |
Secondary Application Category: | calibration, sensitivity, and/or uncertainty analysis |
Watershed Description: | Seven watersheds ranging in size from 1,883 km^2 to 6,616 km^2 in Arkansas, U.S. |
Calibration Summary: | |
Validation Summary: | |
General Comments: | |
Abstract: | There has been a steady shift towards modeling and model-based approaches as
primary methods of assessing watershed response to hydrologic inputs and land
management, and of quantifying watershed-wide best management practice (BMP)
effectiveness. Watershed models often require some degree of calibration and validation to
achieve adequate watershed and therefore BMP representation. This is, however, only
possible for gauged watersheds. There are many watersheds for which there are very little
or no monitoring data available, thus the question as to whether it would be possible to
extend and/or generalize model parameters obtained through calibration of gauged
watersheds to ungauged watersheds within the same region. This study explored the
possibility of developing regionalized model parameter sets for use in ungauged
watersheds. The study evaluated two regionalization methods: global averaging, and
regression-based parameters, on the SWAT model using data from priority watersheds in
Arkansas. Resulting parameters were tested and model performance determined on three
gauged watersheds. Nash-Sutcliffe efficiencies (NS) for stream flow obtained using
regression-based parameters (0.53–0.83) compared well with corresponding values
obtained through model calibration (0.45–0.90). Model performance obtained using global
averaged parameter values was also generally acceptable (0.4 ≤ NS ≤ 0.75). Results from
this study indicate that regionalized parameter sets for the SWAT model can be obtained
and used for making satisfactory hydrologic response predictions in ungauged watersheds. |
Language: | English |
Keywords: | modeling; ungauged watersheds; SWAT; hydrologic calibration |