Title: | Modelling hydrologic processes and NPS pollution in a small watershed in subhumid subtropics using SWAT |
Authors: | Mishra, A. and S. Kar |
Year: | 2012 |
Journal: | Journal of Hydrologic Engineering |
Volume (Issue): | 17(3) |
Pages: | 445–454 |
Article ID: | |
DOI: | 10.1061/(ASCE)HE.1943-5584.0000458 |
URL (non-DOI journals): | |
Model: | SWAT |
Broad Application Category: | hydrologic and pollutant |
Primary Application Category: | pollutant cycling/loss and transport |
Secondary Application Category: | hydrologic assessment |
Watershed Description: | 16.95 km^2 Banha in Jharkhand, in northeast India |
Calibration Summary: | |
Validation Summary: | |
General Comments: | |
Abstract: | SWAT model has been calibrated and validated to predict stream flow, and
transport of sediment and non-point source (NPS) pollutants to the
downstream water resources from a small (1695 ha) watershed in sub-humid
subtropics, that receives variable monsoon rains. Observed rainfall,
temperature, stream flow and sediment yield data for three years have been
utilized to test the model prediction capability of daily stream flow and
sediment yield during the monsoon months from June to October. Because of
the variability of monsoon rains, the model has been calibrated for a normal
rainfall year (M-SD < RF < M+SD and RF = 1.2*M) and then validated for a
relatively dry (RF < M-SD) and a medium rainfall year (RF > M-SD and RF <
0.8M). The results reveal that calibrated model for the normal rainfall year can
be used successfully for predicting hydrologic processes and NPS pollution
for a relatively dry rainfall year, whereas, for the medium rainfall year the
model prediction shows more deviations from the measured values. The
Nash-Sutcliffe efficiencies in dry and medium rainfall years are respectively
0.70 and 0.62 for daily stream flow and 0.73 and 0.69 for daily sediment yield.
NPS pollutants simulation results indicate that calibrated SWAT model can be
used in estimating hydrologic responses related to water quality problems of
watersheds situated in monsoon regions where the nature of rainfall has
shown varying characteristics every year. The results of the study have
implications of watershed management to reduce the sediment and NPS
pollutants load in to downstream water bodies. |
Language: | English |
Keywords: | Modelling, SWAT, runoff, sediment yield, non-point source, pollutants, monsoon rains |