A modeling approach to determine the impacts of land use and climate change scenarios on the water flux of the upper Mara River

Abstract

With the flow of the Mara River becoming increasingly erratic especially in the upper reaches, attention has been directed to land use change as the major cause of this problem. The semi-distributed hydrological model Soil and Water Assessment Tool (SWAT) and Landsat imagery were utilized in the upper Mara River Basin in order to 1) map existing field scale land use practices in order to determine their impact 2) determine the impacts of land use change on water flux; and 3) determine the impacts of rainfall (0%, ±10% and ±20%) and air temperature variations (0% and +5%) based on the Intergovernmental Panel on Climate Change projections on the water flux of the upper Mara River. <br><br> This study found that the different scenarios impacted on the water balance components differently. Land use changes resulted in a slightly more erratic discharge while rainfall and air temperature changes had a more predictable impact on the discharge and water balance components. These findings demonstrate that the model results show the flow was more sensitive to the rainfall changes than land use changes. It was also shown that land use changes can reduce dry season flow which is the most important problem in the basin. The model shows also deforestation in the Mau Forest increased the peak flows which can also lead to high sediment loading in the Mara River. The effect of the land use and climate change scenarios on the sediment and water quality of the river needs a thorough understanding of the sediment transport processes in addition to observed sediment and water quality data for validation of modeling results

Individual and combined effects of land use/cover and climate change on Wolf Bay watershed streamflow in southern Alabama

“…Mango et al . () used SWAT to explore the impacts of LULC and climate change scenarios on the water flux of the upper Mara River in Africa. They found that deforestation resulted in a slightly more erratic discharge while precipitation and air temperature changes had a more predictable impact on the discharge and water balance components.…”

Impacts of climate and land use/cover changes on streamflow at Kibungo sub-catchment, Tanzania

“…Climate change and land use/cover change alter hydrological processes such as surface runoff, base flow, evapotranspiration, and streamflow and impact the variability of these processes over time and space ( Mango et al., 2010 ; Rahman et al., 2015 ). With the advancement in hydrological modeling, researchers globally have been able to investigate the impact of climate change and land use/cover change on hydrology at different scales ( Mahe, 2006 ; Lafontaine et al., 2015 ; Pervez and Henebry, 2015 ; Zhang et al., 2016 ; Thi et al., 2017 ; Yang et al., 2019 ; Osei et al., 2019 ; Nyatuame et al., 2020 ; Ragab, 2020 ; Chim et al., 2021 ; Hu et al., 2021 ; Teklay et al., 2021 ).…”

A comprehensive assessment framework for attributing trends in streamflow and groundwater storage to climatic and anthropogenic changes: A case study in the typical semi‐arid catchments of southern India

“…Modelling is an improved alternative approach to data analysis. Modelling can potentially provide a better understanding of changes in surface and groundwater processes, especially where climatic variability might mask other signals, as well as providing future predictive capabilities (Bouwer et al, 2006; Garg, Singh, et al, 2020; Mango et al, 2010; Singh et al, 2020; Sridhar & Nayak, 2010; Zhan et al, 2014). Typically, several studies have focussed on either surface water hydrology or groundwater hydrology of the catchment using conceptual models.…”