D ebre Mawi is an agricultural watershed in the upper Blue Nile Basin. The slope ranges from 1% t... more D ebre Mawi is an agricultural watershed in the upper Blue Nile Basin. The slope ranges from 1% to 30% and the altitude varies from 2,195 m near the outlet to 2,308 m in the southeast. The area receives a mean annual rainfall of 1,240 mm with most of it concentrated between June and September (Dagnew et al., 2014). Smallholder farmers produce cereals such as teff, maize, finger millet, barley, and wheat, which dominate land use in the watershed, followed by grassland and sparse vegetation. The watershed is characterized by very low vegetation cover, severe sheet, rill and inter-rill erosion, and an active gully formation. The rate of erosion in the region is far beyond the tolerable rate, reaching 36 tons/ha/year from upland erosion (Zegeye et al., 2010) and 234 tons/ha/year from gully erosion (Zegeye et al., 2014). Erosion in the watershed has resulted in a loss of crop productivity due to loss of soil nutrients and land that is severely damaged by gully erosion. Of the 528 ha cove...
Investigation of hydrological processes in few watersheds of the Ethiopian highland indicated the... more Investigation of hydrological processes in few watersheds of the Ethiopian highland indicated the dominance of saturation excess runoff processes. To generalize this in the highland, repeated investigation and replication is necessary. The main focus of this study is twofold 1) Investigating the hydrological response in the new experimental watershed and 2) modeling the rainfall runoff based on Parameter Efficient Semi-Distributed model. The Awramba micro watershed with an area 7km2 was selected for this study as an experimental watershed. Hydrometeorlogical instrumentation on the watershed was done prior to the rainy season. Rainfall, stream flow, ground water table, and infiltration rate was measured in this micro-watershed in the main rainy season of 2013 and 2014. The results showed that the water table readings in the saturated areas rise quicker and stayed longer period than the water table readings at the top and mid slopes of the watershed. The median infiltration rate has b...
As a response to the continuing increasing sediment concentrations in rivers and lakes in the Eth... more As a response to the continuing increasing sediment concentrations in rivers and lakes in the Ethiopian highlands, the Ethiopian government is leading an effort where farmers are installing soil and water conservation practices to reduce erosion. This paper reports on a four year study in the 95 hectare Debre Mawi watershed, in the upper Blue Nile Basin, Ethiopia where at the end of the second year, soil and water conservation practices were installed under a government directed plan. These practices consisted of 50 cm deep infiltration furrows with a vegetated berm down slope. The results showed that the total runoff volume decreased fourfold from 300 mm/year to just 60 mm/year. Flow averaged sediment concentration only reduced slightly from 22 g l-1 to 20 g l-1 mainly because sediment concentrations were determined by the loose soil in the gully that was being formed in the lower periodically saturated part of the watershed. Loads were decreased significantly to around 10 ton per ...
D ebre Mawi is an agricultural watershed in the upper Blue Nile Basin. The slope ranges from 1% t... more D ebre Mawi is an agricultural watershed in the upper Blue Nile Basin. The slope ranges from 1% to 30% and the altitude varies from 2,195 m near the outlet to 2,308 m in the southeast. The area receives a mean annual rainfall of 1,240 mm with most of it concentrated between June and September (Dagnew et al., 2014). Smallholder farmers produce cereals such as teff, maize, finger millet, barley, and wheat, which dominate land use in the watershed, followed by grassland and sparse vegetation. The watershed is characterized by very low vegetation cover, severe sheet, rill and inter-rill erosion, and an active gully formation. The rate of erosion in the region is far beyond the tolerable rate, reaching 36 tons/ha/year from upland erosion (Zegeye et al., 2010) and 234 tons/ha/year from gully erosion (Zegeye et al., 2014). Erosion in the watershed has resulted in a loss of crop productivity due to loss of soil nutrients and land that is severely damaged by gully erosion. Of the 528 ha cove...
Investigation of hydrological processes in few watersheds of the Ethiopian highland indicated the... more Investigation of hydrological processes in few watersheds of the Ethiopian highland indicated the dominance of saturation excess runoff processes. To generalize this in the highland, repeated investigation and replication is necessary. The main focus of this study is twofold 1) Investigating the hydrological response in the new experimental watershed and 2) modeling the rainfall runoff based on Parameter Efficient Semi-Distributed model. The Awramba micro watershed with an area 7km2 was selected for this study as an experimental watershed. Hydrometeorlogical instrumentation on the watershed was done prior to the rainy season. Rainfall, stream flow, ground water table, and infiltration rate was measured in this micro-watershed in the main rainy season of 2013 and 2014. The results showed that the water table readings in the saturated areas rise quicker and stayed longer period than the water table readings at the top and mid slopes of the watershed. The median infiltration rate has b...
As a response to the continuing increasing sediment concentrations in rivers and lakes in the Eth... more As a response to the continuing increasing sediment concentrations in rivers and lakes in the Ethiopian highlands, the Ethiopian government is leading an effort where farmers are installing soil and water conservation practices to reduce erosion. This paper reports on a four year study in the 95 hectare Debre Mawi watershed, in the upper Blue Nile Basin, Ethiopia where at the end of the second year, soil and water conservation practices were installed under a government directed plan. These practices consisted of 50 cm deep infiltration furrows with a vegetated berm down slope. The results showed that the total runoff volume decreased fourfold from 300 mm/year to just 60 mm/year. Flow averaged sediment concentration only reduced slightly from 22 g l-1 to 20 g l-1 mainly because sediment concentrations were determined by the loose soil in the gully that was being formed in the lower periodically saturated part of the watershed. Loads were decreased significantly to around 10 ton per ...
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