Soil Tech Finals 1

41問 • 2年前

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A hazard traditionally associated with agriculture in tropical and semi-arid areas and is important for its long-term effects on soil productivity and sustainable agriculture

Soil Erosion

The detachment and subsequent transport of soil materials (including rock fragments) by an agent (water, wind, or gravity) to an area of deposition.

Soil Erosion

2 General types of erosion

Geologic or Natural Erosion, Accelerated Erosion

this represents the erosion characteristics of the land in its natural environment. undisturbed by human activity.

Geologic or Natural Erosion

this is erosion induced by human activities that have brought about changes in natural cover and soil conditions.

Accelerated Erosion

3 Processes involved during soil erosion by water

Soil Detachment by rainfall, Transportation, Deposition

This is a process by which raindrops splash soil sediments from the soil surface into the runoff

Soil detachment by rainfall

transportation of sediments from upslope to downhill direction, whether in rills, between rills, and sheet flow.

Entrainment/Transportation

This refers to the process of sediment settling out under the action of gravity.

Sediment deposition

Types of erosion

Water erosion, Wind erosion

this is also known as so blowing This may range from a slight disturbance of the soil surface over a small area to the ruge dust storms that sweep across large areas removes countless tons of soil and constitutes a major catastrophe

Wind erosion

a type of erosion caused by rainwater including melted snow running over exposed and surfaces

Water erosion

Types of water erosion

Sheet Erosion, Rill Erosion, Stream Bank Erosion, Gully erosion

this is a type of erosion where runoff from a slope increases cumcently in volume or velocity to cut deep incisions

Gully erosion

this is more or less the removal of a thin layer of soil over an entire sloping and segment.

Sheet Erosion

this is an erosion occurring along the sides of river banks.

Stream Bank Erosion

this is a type of erosion when runoff water generally concentrates on small channels of sufficient velocity and volume to generate increased cutting power

Rill Erosion

Types of Wind erosion

Detrusion, Abrasion

is the wearing a way of rocks and toll projections by fine particles camed in suspension

Detrusion

a similar action takes place close to the ground where the moving particles are larger and bouncing along over the surface

Abrasion

Forms by Which Materials are Carried Away

Extrusion, Efflusion, Efflution

Types of Particle Movement by Wind Action

Suspension, Creep, Saltation

particles of intermediate size move off downwind into the bouncing action called?

Efflusion

the removal of very fine particles.

Efflution

the rolling away by large particles.

Extrusion

bouncing movement of particles

Saltation

is the movement by very fine particles, mainly less than 0.1 mm diameter. Stoke's Law relates the speed of a body falling through a fluid to the square of the particle diameter, and the falling speed of such small particles is so low that once lifted,

Suspension

rolling movement of particles

Creep

Factors influencing the rate of erosion

Rainfall, Soil erodability, Vegetation or Plant cover, Relief (slope), Human Activities

The potential capacity of the rain to cause erosion is called

erosivity

this is the climatic element that mainly affects erosion in the humid tropics

Rainfall

is defined as the fineness or coarseness of soil particles.

Soil texture

this refers to the vulnerability or proneness of the soil to erosion.

Soil erodability

which is the arrangement of primary particles into aggregates

Soil Structure

Both the slope steepness and slope length affect erosion and runoff behavior.

Relief (slope)

particularly the removal of vegetative cover thru shifting cultivation and deforestation results in accelerating soil erosion

Human Activities

Human activities that affect soil erosion

overgrazing, burning, road construction, urbanization, mining, Shifting agriculture

this occurs when animals eat top leaves

overgrazing

effects outside agriculture

off-site effect

effects of soil erosion of farmer's fields

Onsite effect

soil structure

granular , columnar, prismatic , platy, single Grained , blocky

Soil Tech Midterm 1

Mutated Lemon · 100問 · 2年前

Soil Tech Midterm 1