Integrated Hydrologic-Hydrodynamic Inundation Modeling in a Groundwater Dependent Tropical Floodplain

Abstract

The rapid development of free and open-access hydrological models and coupling framework tools continues to present more opportunities for coupled model development for improved assessment of floodplain hydrology. In this study, we set up an Upper Zambezi hydrological model and a fully spatially hydrological-hydrodynamic coupled model for the Barotse Floodplain using GLOFRIM (GLObally applicable computational FRamework for Integrated hydrological–hydrodynamic Modelling). The hydrological and hydrodynamic models used are WFLOW and LISFLOOD-FP, respectively. The simulated flows generated by the wflow model for the upstream gauge stations before the Barotse Floodplain were quite similar and closely matched the observed flow as indicated by the evaluation statistics; Chavuma, nse = 0.738; kge = 0.738; pbias = 2.561 and RSR = 0.511; Watopa, nse = 0.684; kge = 0.816; pbias = 10.577 and RSR = 0.557; and Lukulu, nse = 0.736; kge = 0.795; pbias = 10.437 and RSR = 0.509. However, even though the wflow hydrological model was able to simulate the upstream hydrology very well, the results at the floodplain outlet gauge stations did not quite match the observed monthly flows at Senanga gauge station as indicated by the evaluation statistics: nse = 0.132; kge = 0.509; pbias = 37.740 and RSR = 0.9233. This is mainly because the representation of both floodplain channel hydrodynamics and vertical hydrological processes is necessary to correctly capture floodplain dynamics. Thus, the need for an approach that saves as a basis for developing fully spatially distributed coupled hydrodynamic and hydraulic models’ assessments for groundwater dependent tropical floodplains such as the Barotse floodplain, in closing the gap between hydrology and hydrodynamics in floodplain assessments. A fully coupled model has the potential to be used in implementing adaptive wetland management strategies for water resources allocation, environmental flow (eflows), flood control, land use and climate change impact assessments. Doi: 10.28991/HEF-2022-03-02-09 Full Text: PDF

Integrated use of the CA-Markov model and the Trends.Earth module to enhance the assessment of land cover degradation: Application in the Upper Zambezi Basin, southern Africa

“…The UZB is susceptible to climatic hazards such as droughts and floods, and has witnessed a rise in mining activities, population, and human settlements (Hughes & Farinosi, 2020;Beilfuss, 2012). Studies conducted in the Upper Zambezi Basin have primarily focused on the hydrology and ecology of the basin, particularly with regard to the associated climate implications (Chomba et al, 2022;Makungu & Hughes, 2021;Zimba et al, 2018;Timberlake, 2000). Some studies have also examined changes in Land Cover and Land Use (LCLU) within the Upper Zambezi Basin, both at a broader level and in specific areas of Angola (Kissanga et al, 2024) and Zambia (Banda et al, 2023;Tiamgne et al, 2021;Phiri et al, 2019;Shakachite et al, 2016).…”

Applying Floodplain Inundation Modeling to Estimate Suitable Spawning Habitat and Recruitment Success for Alligator Gar in the Guadalupe River, Texas

“…Traditional hydraulic flood inundation models, originally developed for societal flood risk and hazard mitigation applications, are increasingly being used for research on flowecology relationships involving flood processes [1][2][3] and wetland management [4]. Ecological functions and species life-history adaptations in riverine systems occur in response to different spatial and temporal dimensions of longitudinal, lateral, vertical, and temporal hydrologic connectivity that vary with flood dynamics [5][6][7].…”

“…The present study does not evaluate hydrodynamics of wetting and drying, antecedent wetted/inundated conditions, or changes to flood depth during a high pulse or flood event. This limitation is a commonly recognized challenge when using flood models for ecological analyses [4]. Our study does not incorporate aspects of fish movement during inundation [10,23], intra-species competition for spawning habitats, predation pressures on juveniles following successful spawning, or persistence of inundated off-channel nursery habitat and forage resources for rearing juvenile Alligator Gar [8].…”

Utilization Management to Ensure Clean Water Sources in Coastal Areas

“…Source, distribution, and purification reclaim fifty percent of the water [29]. Population, surface and groundwater quality, and regional factors have a significant impact on water availability [30]. It necessitates littoral water quality management.…”

“…Figure 4 displays relative water temperature conditions that meet the 10-25 o C clean water standard not too far from the air temperature on the surface, except on the coast where the water temperature exceeds the existing standard of 28.50 o C and Simon et al[69] state that streams with coverage in watershed temperature patterns are necessary for water development and utilization, while water temperature measurement depends on the season[70]. For water salinity, points 1 and 2 indicate saltwater conditions(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40), point 3 indicates brackish water conditions, and points 4 and 5…”