SOIL 2124 EXAM 4 WITH COMPLETE SOLUTIONS 100% VERIFIED!!!
ALREADY GRADED A+
Mechanical/Engineering Measures - (ANSWER)1. Riprap
2. Terracing
3. Bioenginerring
4. Sediment Traps
5. Retention Ponds
Riprap - (ANSWER)Large angular rocks may be laid at the bottom or the side of channels where high
water velocities may be expected
What kind of erosion counts for more than 40 percent of total soil loss in some watersheds -
(ANSWER)Steam-Bank Erosion
Terracing - (ANSWER)"Stairs-like" surface manipulation to reduce down-slope runoff velocity and
encourage retention of sediments
Not very common in the US
Bioengineering - (ANSWER)Use of vegetation to protect channels, reduce runoff velocity and trap
sediements
Sediment Traps - (ANSWER)Traps are designed to:
1. Slow down runoff
2. Trap sediments
Retention Ponds/Sedimentation Basins - (ANSWER)Ponds constructed down-slope of field which collects
runoff and allows sediments to settle prior to movement of surface water off-site
Wind Erosion in the US Key facts - (ANSWER)1. Wind moves 40% of the soil transported by erosion in the
US
2. Problem in 75 million acres of land in the US
, SOIL 2124 EXAM 4 WITH COMPLETE SOLUTIONS 100% VERIFIED!!!
ALREADY GRADED A+
3. Up to 29 mg/ha of wind erosion-induced losses had been recorded in New Mexico
Three processes of wind erosion - (ANSWER)Detachment, Transportation, and Deposition
Factors affecting wind erosion - (ANSWER)1. Wind velocity
2. Surface roughness
3. Soil properties
Wind Velocity - (ANSWER)Areas with steady, prevailing winds are very prone to wind erosion
Wind-carried sediments that strike the ground further increases the detachment process
Threshold Velocity - (ANSWER)25 km/h at 12 inches above the ground
Soil Roughness - (ANSWER)Smooth soil surface devoid of vegetative cover- more susceptible to wind
erosion
The rougher the surface, the less severe the erosion is
Soil Properties - (ANSWER)Moisture content. Those areas with low annual rainfall are most vulnerable
Stability of clods arrogates
Size of erodible fraction
Modes of wind-induced transportation - (ANSWER)1. Saltation
2. Soil creep
3. Suspension
Saltation - (ANSWER)Movement of soil by a series of short bounces along the ground surfaces
May account for 50-90% of the soil movement
ALREADY GRADED A+
Mechanical/Engineering Measures - (ANSWER)1. Riprap
2. Terracing
3. Bioenginerring
4. Sediment Traps
5. Retention Ponds
Riprap - (ANSWER)Large angular rocks may be laid at the bottom or the side of channels where high
water velocities may be expected
What kind of erosion counts for more than 40 percent of total soil loss in some watersheds -
(ANSWER)Steam-Bank Erosion
Terracing - (ANSWER)"Stairs-like" surface manipulation to reduce down-slope runoff velocity and
encourage retention of sediments
Not very common in the US
Bioengineering - (ANSWER)Use of vegetation to protect channels, reduce runoff velocity and trap
sediements
Sediment Traps - (ANSWER)Traps are designed to:
1. Slow down runoff
2. Trap sediments
Retention Ponds/Sedimentation Basins - (ANSWER)Ponds constructed down-slope of field which collects
runoff and allows sediments to settle prior to movement of surface water off-site
Wind Erosion in the US Key facts - (ANSWER)1. Wind moves 40% of the soil transported by erosion in the
US
2. Problem in 75 million acres of land in the US
, SOIL 2124 EXAM 4 WITH COMPLETE SOLUTIONS 100% VERIFIED!!!
ALREADY GRADED A+
3. Up to 29 mg/ha of wind erosion-induced losses had been recorded in New Mexico
Three processes of wind erosion - (ANSWER)Detachment, Transportation, and Deposition
Factors affecting wind erosion - (ANSWER)1. Wind velocity
2. Surface roughness
3. Soil properties
Wind Velocity - (ANSWER)Areas with steady, prevailing winds are very prone to wind erosion
Wind-carried sediments that strike the ground further increases the detachment process
Threshold Velocity - (ANSWER)25 km/h at 12 inches above the ground
Soil Roughness - (ANSWER)Smooth soil surface devoid of vegetative cover- more susceptible to wind
erosion
The rougher the surface, the less severe the erosion is
Soil Properties - (ANSWER)Moisture content. Those areas with low annual rainfall are most vulnerable
Stability of clods arrogates
Size of erodible fraction
Modes of wind-induced transportation - (ANSWER)1. Saltation
2. Soil creep
3. Suspension
Saltation - (ANSWER)Movement of soil by a series of short bounces along the ground surfaces
May account for 50-90% of the soil movement
