摘要
Located in the semi-arid zone of Zambia, the Mutama-Bweengwa, Kasaka and Magoye sub-catchments have witnessed a high demand for water due to increase in population and socio-economic activities putting more pressure on water resources. This study assesses the hydrological components and ascertains the available water resources and unmet demand in the sub-catchments using the Water Evaluation And Planning (WEAP) Model and hydrometeorological data collected between 1951 and 2018. The model was calibrated and validated on 1971-1981 and 2008-2018 data respectively. The results reveal that the sub-catchments have transitioned from positive to negative water balance with -164.295 Mm<sup>3</sup>/year for Mutama-Bweengwa, -19.021 Mm<sup>3</sup>/year for Kasaka and -86.368 Mm<sup>3</sup>/year for Magoye. Evaporation was 1815.259 Mm<sup>3</sup>/year for Mutama-Bweengwa, 1162.655 Mm<sup>3</sup>/year for Kasaka and 1505.664 Mm<sup>3</sup>/year for Magoye. The demand for water has been increasing over time for various purposes such as irrigation, domestic, urban/rural water supply and livestock. The overall water storage in the sub-catchments showed a negative water balance for the year 2018. The observed and simulated peak streamflow were 8.16 m<sup>3</sup>/s and 7.7 m<sup>3</sup>/s occurring during the month of January and February respectively. The WEAP model performance achieved R<sup>2</sup> of 0.98 during calibration and 0.95 for validation, and an NSE of 0.83 for calibration and 0.85 during validation. The values of objective functions show that the hydrology of the Mutama-Bweengwa, Kasaka and Magoye sub-catchments as predicted by the WEAP model provides satisfactory confidence for prediction of future streamflow and hence projection based on future scenarios.
Located in the semi-arid zone of Zambia, the Mutama-Bweengwa, Kasaka and Magoye sub-catchments have witnessed a high demand for water due to increase in population and socio-economic activities putting more pressure on water resources. This study assesses the hydrological components and ascertains the available water resources and unmet demand in the sub-catchments using the Water Evaluation And Planning (WEAP) Model and hydrometeorological data collected between 1951 and 2018. The model was calibrated and validated on 1971-1981 and 2008-2018 data respectively. The results reveal that the sub-catchments have transitioned from positive to negative water balance with -164.295 Mm<sup>3</sup>/year for Mutama-Bweengwa, -19.021 Mm<sup>3</sup>/year for Kasaka and -86.368 Mm<sup>3</sup>/year for Magoye. Evaporation was 1815.259 Mm<sup>3</sup>/year for Mutama-Bweengwa, 1162.655 Mm<sup>3</sup>/year for Kasaka and 1505.664 Mm<sup>3</sup>/year for Magoye. The demand for water has been increasing over time for various purposes such as irrigation, domestic, urban/rural water supply and livestock. The overall water storage in the sub-catchments showed a negative water balance for the year 2018. The observed and simulated peak streamflow were 8.16 m<sup>3</sup>/s and 7.7 m<sup>3</sup>/s occurring during the month of January and February respectively. The WEAP model performance achieved R<sup>2</sup> of 0.98 during calibration and 0.95 for validation, and an NSE of 0.83 for calibration and 0.85 during validation. The values of objective functions show that the hydrology of the Mutama-Bweengwa, Kasaka and Magoye sub-catchments as predicted by the WEAP model provides satisfactory confidence for prediction of future streamflow and hence projection based on future scenarios.
作者
Tewodros M. Tena
Alick Nguvulu
Dickson Mwelwa
Phenny Mwaanga
Tewodros M. Tena;Alick Nguvulu;Dickson Mwelwa;Phenny Mwaanga(Department of Environmental Engineering, Copperbelt University, Kitwe, Zambia;Department of Geomatics Engineering, Copperbelt University, Kitwe, Zambia;Business and Information Technology Department, Cavendish University, Lusaka, Zambia)
