Understanding gully erosion dynamics and extent is essential when developing gully erosion management strategies. This paper aims to investigate suspended sediment production and dynamics during precipitation-runoff events in the Upper Blue Nile basin in Ethiopia. Runoff events measured between 2017 and 2020 can be used to study the relationship between runoff and sediment and suspended sediment dynamics. During the study period, the overall discharge coefficient of variation (CV) varied between 55.2 and 66.5% at the head and 52.2 and 64.9% at the tail. Therefore, increasing runoff could increase sediment transport capacity, increasing sediment discharge. As a result, the soil amount estimated using gully parameters for 2017, 2018, 2019, and 2020 was 1962.4, 1097.4, 1033.6, and 1254.3 Mg yr–1, respectively. Between 2017 and 2020, CVs for total sediment load values ranged from 65.1 to 96.1% at the head and 17.1 to 78.1% at the tail. In the gully tail, sediment yield was higher than in the head, suggesting gully sediment contributed more to sediment yield than large upland catchments. As a result of the study, we have been able to develop practical recommendations for managing gully erosion in the future. A sediment budget calculation and a hysteresis loop analysis of the monitored site demonstrated that nearly 85% of the sediment came from the gully. The findings provided valuable information for runoff patterns and suspended sediment dynamics, and enhanced sediment control theory at the study site and in other similar environmental settings.

Mesenbet Yibeltal
Faculty of Civil and Water Resource Engineering, Bahir Dar University, Ethiopia
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