| Title: | Using a hierarchical approach to calibrate SWAT and predict the semi-arid hydrologic regime of northeastern Brazil |
| Authors: | Santos, C.A.S., C. Almeida, T.B. Ramos, F.A. Tocha, R. Oliveira and R. Neves |
| Year: | 2018 |
| Journal: | Water |
| Volume (Issue): | 10(9) |
| Pages: | |
| Article ID: | 1137 |
| DOI: | 10.3390/w10091137 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | calibration, sensitivity, and/or uncertainty analysis |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 55,317 km^2 Paraguaçu river, located in the east central part of the state of Bahia in northeast Brazil. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | The Paraguaçu watershed in northeastern Brazil faces increasing water scarcity, with
water resources unable to meet the increasing demand. Accurate assessment of water availability is
thus essential for efficient planning and management of local resources. In this work, the potential
of the SWAT model for predicting daily and monthly variability of the hydrologic regime of the
Paraguaçu River was assessed. Model calibration/validation followed: (i) A hierarchical framework;
(ii) the assessment of maximum, average and minimum streamflow based on paired t-test and linear
regression analysis; and (iii) the definition of permanence curves for streamflow with a probability
of occurrence of 90% (Q90) and 95% (Q95). The goodness-of-fit indicators revealed a “satisfactory”
model performance (model efficiency ranged from 0.42 to 0.83) when predicting streamflow in
monitored sub-basins using a unique set of parameters for wet and dry conditions. The flow duration
curves also showed that the model underestimated higher flows resulting from extreme events
but performed well for flows with exceedance probabilities of <90%. The regression analysis and
paired t-test demonstrated that the SWAT model can be used for estimating maximum, average
and minimum monthly streamflow in a region where information is insufficient to support water
authorities in the decision-making process. The SWAT model can thus be considered adequate for
simulating monthly streamflow in the Paraguaçu watershed. |
| Language: | English |
| Keywords: | hydrologic process; semiarid; Paraguaçu watershed; hierarchical scheme; SWAT |