EROSION Flashcards
______ is the earth’s fragile skin that anchors all life on Earth. It is comprised of countless species that create a dynamic and complex ecosystem and is among the most precious resources to humans.
Soil
- the mechanical process of wearing or grinding something down
- geological process in which earthen materials are worn away and transported by natural forces such as wind or water
- physical process in which soil, rock, and other surface material are removed from one location and transported to another
Erosion
TYPES OF EROSION:
a. WIND EROSION
b. GULLY EROSION
c. RILL EROSION
d. WATER EROSION
e. SHEET EROSION
f. ATTRITION
g. ABRASION
h. SPLASH
i. TUNNEL
j. GLACIAL
______ (or eolian) erosion (named after Aeolus, the Greek god of winds) and occurs almost always in deserts.
aeolian
__________ of sand in the desert is partially responsible for the formation of sand dunes. The power of the wind erodes rock and sand.
Aeolian erosion
rill erosion is form of water erosion in which the erosion takes place through numerous narrow and more or not so straight channels called _________.
streamlets or head cuts
_____ is the most common form of erosion, which you can also observe during heavy rain.
Rill
It is the uniform removal of soil in thin layers from the land surface caused by the wind. Land areas with loose, shallow topsoil overlying compact soil are most prone to ________
SHEET EROSION
_______ occurs due to the runoff of surface water, causing the removal of soil with drainage lines.
Gully erosion
______ when started once, will move by headward erosion or even by slumping of side walls unless and un-till proper steps will be taken in order to stabilize the disturbance.
Gullies
results from the bombardment of the soil surface by rain drops.
SPLASH EROSION
The erosion due to the impact of falling raindrops on the soil surface leading to the destruction of the crumb structure is known as ______________
raindrop or splash erosion.
the removal of subsoil. When water penetrates through a soil crack or a hole where a root has decayed, the soil disperses and is carried away with the flow to leave a small tunnel.
TUNNEL EROSION
the process of erosion produced by the suspended particles that impact on solid objects. Windblown grains of sand, carried along at high speed, are a very effective tool that can sandblast away rocks by _______.
ABRASION EROSION
caused by the detachment and transport of soil by rainfall, runoff, melting snow or ice, and irrigation. occurs when rain or snowmelt displaces the soil on the ground.
WATER EROSION
Land that has ____________—including farm fields that are left barren after crop harvest—are especially vulnerable to water erosion
no vegetation
the process of erosion that occurs during rock collision and transportation.
ATTRITION EROSION
The transportation of sediment chips and smooths the surfaces of bedrock; this can be through water or wind. Rocks undergoing attrition erosion are often found on or near the bed of a stream
ATTRITON EROSION
- this is when pebbles grind along a rock platform, much like sandpaper. Over time the rock becomes smooth.
Abrasion
- this is when rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded.
Attrition
processes that occur directly in association with the movement of glacial ice over its bed, such as abrasion, quarrying, and physical and chemical erosion by subglacial meltwater, as well as from the fluvial and mass wasting processes that are enhanced or modified by glaciation.
GLACIAL EROSION
KINDS OF EROSION:
a. ACCELERATED
b. GEOLOGIC
- Due to man made activities, which brought changes in natural land cover and soil conditions
ACCELERATED EROSION
ACCELERATED EROSION activities include:
- land preparation for raising crops
- land use patterns for building houses, infrastractures, industries, hill cutting, deforestation, lack of soil concervation and watershed management.
________ happens when the rate of soil loss is higher than the rate of soil formation.
Accelerated erosion
__________ results from the removal of natural vegetation by human activities such as farming, ranching, forestry, and construction.
Accelerated erosion
- Production of agricultural and forest products can be affected by excessive erosion
ACCELERATED EROSION
_____ is defined as an action of surface that removes soil particles and rocks from one location to another on the earth’s surface.
Erosion
_______ occurs naturally, but human activities can make erosion occur.
Erosion
The major causes of erosion are:
human activities and natural processes.
_______ erosion caused by geological processes acting over long geologic periods and resulting in the wearing away of mountains, building up of floodplains, coastal plains, etc. Synonymous with natural erosion.
normal or natural
This type of erosion contributes to the formation of soils and their distribution on the earth surface.
natural or normal erosion.
The geologic erosion is a longtime eroding process.
natural or normal erosion.
ANTHROPOGENIC ACTIVITIES:
HUMANS
NEEDS AND WANTS CHANGES IN NATURAL COVER AND SOIL CONDITIONS
TYPES OF EROSION ACC. TO ACTIVE FORCES:
1.WIND EROSION
2. GRAVITY EROSION
c. WATER EROSION
Erosion in low rainfall areas
WIND EROSION
GRAVITY EROSION
Movement of soil due to its own weight:
a. SOIL CREEP
b. Landslide
- slow movement of soil sometimes not perceptible
SOIL CREEP
- sudden movement of landmass of soil and rocks
Landslide
Landslide- sudden movement of landmass of soil and rocks caused by:
a. increased weight of soil
b. undercutting by stream banks
c. faulty drainage
d. cutting of trees
e. earthquake
f. internal movement in geologicformation
Erosion caused by movement of water
WATER EROSION
HUMAN INTERFERENCE CAUSING EROSION:
1.Logging and fuel cutting
2. kaingin making
6. improper dispossal of mining waste
3. forest fire and grassland burning
4. improper range management
5. road cuts
7. Improper drainage
EFFECTS OF EROSION:
1.Deterioration of farmlands
2. Increase of floods
3. reduction of water supply
4. siltation of reservoirs, canals and rivers
5. Destruction of buildings, roads and other communication lines
PREVENTIVE MEASURES AGAINST EROSION
1.educational campaign
2. fire prevention control
3. fencing
4. proper land use
5. proper range management
* prescribed burning
* pasture rotation
* pastural improvement
EROSION CONTROL MEASURES:
1.ENGINEERING/ STRUCTURAL MEASURES
2. Biological/ Vegetative measure
3. Vengineering measures
4. Agroforestry
5.Reforestation/Afforestation
ENGINEERING/ STRUCTURAL MEASURES:
A. Masonry
B. Concrete
C. Gabions
-stone walls or riprapping with or without cement
Masonry
- cement with reinforcement bars
Concrete
- large rectangular wire crates that are filled with stones
Gabions
Biological/ Vegetative measure:
A. Wattling
B. saturation planting
C. Bench brush layers
E. Fascines
F. Sodding
- interwove brush wood across slopes
Wattling
- plantng crops with very close spacing to cover the soil
saturation planting
- bundle of grassess laid across the slope
Fascines
- Matting the soil to grasses
Sodding
- combination of vegetative and engineering measures, which are usually established on the eroded areas for erosion control, and along creeks to trap sediments.
Vengineering measures
- land use management system, which combines the production of agricultura crops, forest trees and or livestock simultaneously or sequentially on the same unit of land.
Agroforestry
- the restoration of the original forest by planting seedlings
Reforestation/Afforestation
