| Title: | Modeling climate and landuse change impacts on streamflow and sediment yield of an agricultural watershed using SWAT |
| Authors: | Ndulue, E.L. and C.C. Mbajiorgu |
| Year: | 2018 |
| Journal: | Agricultural Engineering International: CIGR Journal |
| Volume (Issue): | 20(4) |
| Pages: | 15-25 |
| Article ID: | |
| DOI: | |
| URL (non-DOI journals): | http://www.cigrjournal.org/index.php/Ejounral/article/view/4837 |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | climate change and land use change |
| Secondary Application Category: | sediment loss and transport |
| Watershed Description: | Upper Ebonyi river, located in south central Nigeria. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | Quantifying the hydrological response due to changes in climate and land-use is imperative for the proper management
of water resources within a watershed. The impact of climate and land-use changes on the hydrology of the Upper Ebonyi river
(UER) watershed, South East Nigeria, was studied using the Soil and Water Assessment Tool (SWAT) hydrological model. A
climatological time series analysis from 1985-2014 using non-parametric test showed significant negative trends in precipitation
and relative humidity trend while minimum and maximum temperature, solar radiation and wind speed showed significant
positive trends. Future hypothetical land-use change scenarios representing urbanization and conversion of forest to agricultural
land were combined with future downscaled climate model (CSIRO-Mk3-6-0) and simulated in SWAT model. Scenario 1
represents urbanization and climate data of 2020-2030; Scenario 2 represents urbanization and climate data of 2040-2050;
Scenario 3 represents conversion of forest to agricultural land and climate data of 2020-2030 and Scenario 4 represents
conversion of forest to agricultural land and climate data of 2040-2050 while the Baseline Scenario is the present land-use and
climate data of 2005-2014. Relative to the Baseline (2005-2014), the results showed a decrease in streamflow by 10.3%, 26.2%,
11.8% and 26.72% for Scenarios 1, 2, 3, and 4 respectively, while sediment yield decreased by 7.54%, 19.4%, 11.1% and 9.01%
for Scenarios 1, 2, 3, and 4 respectively. The results suggest development of adaptation strategies to cope with the predicted
hydrological conditions under future climate and land-use change in the watershed. |
| Language: | English |
| Keywords: | climate change, land-use change, swat model, hydrology, upper ebonyi watershed |