H2Open Journal (Dec 2023)
Spatiotemporal changes of land use in response to runoff and sediment yield for environmental sustainability in the upper Blue Nile Basin, Oromiyaa, Ethiopia
Abstract
Modeling and mapping hydrological responses of runoff and sediment yield to spatiotemporal land use changes are crucial concerning environmental sustainability. The research was aimed at quantifying the spatiotemporal effects of land use on runoff and sediment yields using three land use satellite images and the SWAT+ model. The increase in agriculture, settlement, and decreasing forest goes to the possibility of increasing sediment yield and runoff by 53.2 and 56.5%, respectively, affecting ecosystems. The areas vulnerable to high runoff were found at the lower and middle reaches with the annual average runoff of 10,825.1, 11,972.9, and 13,452 mm for each respective scenario. On the other hand, most of the soil erosion-prone areas designated as severe in the second and third scenarios were covered by agriculture and shrubland, with annual sediment yields of 301.5 and 267.5 tons, respectively. Deforestation for agricultural expansion has a significant role in environmental degradation, as forests play an irreplaceable role in ecological resilience. Generally, the dominant land uses that instigate soil erosion, runoff, and sediment yield are agriculture, shrubland, and deforestation. The simulation of runoff and sediment yield in response to land use change using the SWAT+ model is more scientifically reliable and acceptable. HIGHLIGHTS The main new part of this study focused on the applicability of the SWAT+ model in examining the response of land use change to sediment yield and runoff.; In addition, the novel metric in this study was the assessment of the role of each LULC change response to extreme hydrology.; The SWAT+ model has not yet been applied in the upper Blue Nile Basin.;
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