Calibration and validation of the SWAT’s hydrologic
component were performed by comparing
predicted stream flows with corresponding in-stream
measurements for four years (2000-2003) at four
gaging stations within the Chi River Subbasin II in
Northeast Thailand. Statistical comparisons of
calibration results with observed data indicated a
reasonable agreement for both monthly coefficient of
determination (r2) and Nash-Sutcliffe Coefficient (E)
with the ranges of 0.77-0.88 and 0.55-0.79, respectively.
The model validation results showed lower
values of r2 and E values ranging from 0.23 to 0.77
and -7.98 to 0.66. In summary, the overall evaluation
of the SWAT demonstrated that the model has the
capability to predict stream flows within the Chi River
Subbasin II in northeast Thailand. Therefore, to
improve on this model performance, detailed and
long-term data will be needed for further analyses.