ErosionBy Jared Mellody

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In association with

2nd Hour Earth Science

Definition

• The process of eroding or

being eroded by wind, water,

or other natural agents.

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5 Agents of Erosion

• 1. Wind

• 2. Running water

• 3. Glaciers (Ice)

• 4. Waves

• 5. Gravity

• What they are ↓

• The direct source of movement that can cause erosion through

the transfer of energy or transport of rock material.

3

Agent of Erosion: Wind

• Wind erosion damages land

and natural vegetation by

removing soil from one place

and depositing it in another.

4

Agent of Erosion: Running

Water• Running water is the most

powerful agent of erosion.

Continents are eroded

primarily by running water at

an average rate of 1 inch every

750 years. The velocity of a

stream increases as its

gradient increases but velocity

is also influenced by factors

such as degree of turbulence,

position within the river, the

course of the stream, the

shape of the channel and the

stream load.

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Agent of Erosion: Ice

• Ice erosion is the process of

large chunks of ice, known as

glaciers, eroding an area over

a long period of time with the

help of gravity.

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Agents of Erosion:

Waves

• Coastal erosion is the wearing

away of land and the removal

of beach or dune sediments by

wave action.

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Agent of erosion: Gravity

• Gravity can pull rocks and soil

loose from the sides of

mountains and cause

rockslides and mudslides.

8

Logging effects on erosion

• Logging affects the soil by

degrading soil fertility and

reduces crop production.

9

Construction effects on

erosion

• Construction such as Grading

and filling drastically reduce

the soil quality and over time if

unprotected may affect more

areas.

10

Effects of Farming

• Farming has many impacts on

erosion and waterways. In

erosion top soil may be picked

up by wind and or washed

away by rain.

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Conservation Farming -

Terraces

• a terrace is a piece of sloped

plane that has been cut into a

series of successively receding

flat surfaces or platforms,

which resemble steps, for the

purposes of more effective

farming.

• Terraces save soil and improve

water quality over periods of

time.

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Conservation Farming -

Contour Farming• Contour farming is the farming

practice of ploughing and/or

planting across a slope

following its elevation contour

lines.

• Farming on the contour creates

small ridges that slow runoff

water, and it increases the rate

of water infiltration, reduces the

hazard of erosion, and

redirects runoff from a path

directly downslope to a path

around the hills slope.

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Conservation Farming - Wind

Breaks

• A windbreak is a plantation

usually made up of one or

more rows of trees or shrubs

planted in such a manner as to

provide shelter from the wind

and to protect soil from erosion

• Windbreaks protect the land

from erosion by congaing the

amount of dirt in the air.

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Conservation Farming - Strip

Cropping

• Strip cropping is a method of

farming used when a slope is

too steep or too long, or

otherwise, when one does not

have an alternative method of

preventing soil erosion.

• Strip cropping helps keep the

soil in on a long stretch of land.

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Conservation Farming - No-

Till• No-till farming is a way of

growing crops or pasture from

year to year without disturbing

the soil through tillage.

• No-till improves soil quality

(soil function), carbon, organic

matter, aggregates,protecting

the soil from

erosion,evaporation of water,

and structural breakdown. A

reduction in tillage passes

helps prevent the compaction

of soil.

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Conservation Farming -

Cover Crops

• A cover crop is a crop planted

primarily to manage soil

erosion, soil fertility, soil

quality, water, weeds, pests,

diseases, biodiversity and

wildlife.

• Although cover crops can

perform multiple functions in an

agroecosystem

simultaneously, they are often

grown for the sole purpose of

preventing soil erosion.

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Mass Movement

• Mass movement is the movement of surface

material caused by gravity.

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4 triggers of Mass Movement

• Creeps

• The combination of small

movements of soil or rock in

different directions over time

are directed by gravity

gradually downslope

• Landslides

• A landslide, also called a

landslip, is a rapid movement

of a large mass of earth and

rocks down a hill or a

mountainside

• Slump

• A slipping of coherent rock

material along the curved

surface of a decline

• Falls

• It is where regolith cascades

down a slope, but is not of

sufficient volume or viscosity

to behave as a flow.

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Mass Movement - Rockfalls

• Rock falls are when rock slides

off the sides of mountains or

cliffs.

• Triggers include: Frost

wedging, weathering, root

wedging, and external

stresses.

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Mass Movement - Rock

slides

• A rockslide is a type of

landslide caused by rock

failure in which part of the

plane of failure passes through

intact rock and material

collapses en masse and not in

individual blocks.

• Happen on sides of ledges with

rocks that have been

weathered.

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Mass Movement - Slump

• A slipping of coherent rock

material along the curved

surface of a decline

• Causes of slumping include

earthquake shocks,

thorough wetting, freezing

and thawing, undercutting,

and loading of a slope.

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Mass Movement - Mudflow

• A mudflow or mud flow is a

form of mass wasting involving

"very rapid to extremely rapid

surging flow" of debris that has

become partially or fully

liquified by the addition of

significant amounts of water to

the source material.

• Happens where there is a

significant amount of rain over

a period of time.

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Mass Movement - Earth flow

• An earth flow is a downslope

viscous flow of fine-grained

materials that have been

saturated with water, and

moves under the pull of gravity.

• Happens in areas downhill that

have had a significant amount

of rain over a period of time.

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Mass Movement - Creep

• Creep is the tendency of a

solid material to move slowly or

deform permanently under the

influence of mechanical

stresses.

• Creep happens on sides of

roadways and hills.

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Citations (in order by slide)

• https://www.flickr.com/photos/bertknot/9502855842/

• http://commons.wikimedia.org/wiki/File:Rhizolith_group_revealed_after_wind_erosion_3.JPG

• http://commons.wikimedia.org/wiki/File:Urban_stream_in_park.jpg

• http://en.wikipedia.org/wiki/Glacier#mediaviewer/File:Perito_Moreno_Glacier_Patagonia_Argentina_Luca_Galuzzi_2005.JPG

• http://www.geograph.org.uk/photo/3841186

• http://en.wikipedia.org/wiki/Frank_Slide#mediaviewer/File:Frank_Slide,_Canada.jpg

• http://upload.wikimedia.org/wikipedia/commons/a/ab/Logging_road_East_Kalimantan_2005.jpg

• http://s0.geograph.org.uk/geophotos/02/57/62/2576240_25bae00c.jpg

• http://upload.wikimedia.org/wikipedia/commons/4/4f/Chickamauga_Dam_(1936)_-_Dam_construction_erosion_control.jpg

• http://upload.wikimedia.org/wikipedia/commons/9/9a/Silt_fence_EPA.jpg

• http://s0.geograph.org.uk/geophotos/01/56/59/1565950_b4bc2411.jpg

• http://pixabay.com/static/uploads/photo/2013/07/19/00/18/food-165214_640.jpg

• http://upload.wikimedia.org/wikipedia/commons/d/df/Batad_Rice_Terraces.jpg

• http://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/TerracesBuffers.JPG/640px-TerracesBuffers.JPG

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Citations Cont. (in order by slide)

• http://watershedbmps.com/wp-content/uploads/2012/09/ContourFarming_plantandsoil_unl_edu.jpg

• http://cottontoday.cottoninc.com/natural-resources/soil/images/organic.jpg

• http://www.mda.state.mn.us/protecting/conservation/practices/~/media/Images/protecting/practices/fieldwindbreak1.

ashx?w=300&h=214&as=1

• http://www.mda.state.mn.us/protecting/conservation/practices/~/media/Images/protecting/practices/fieldwindbreak2.

ashx?w=300&h=214&as=1

• http://upload.wikimedia.org/wikipedia/commons/0/0b/Cotton_Production_in_the_North_Carolina_Coastal_Plain.jpg

• https://c2.staticflickr.com/6/5075/5878650615_bc834fa040_b.jpg

• https://c1.staticflickr.com/9/8032/8053619620_11c351fd20_b.jpg

• http://upload.wikimedia.org/wikipedia/commons/e/ea/Rockfall.jpg

• http://www.landforms.eu/shetland/images/villians_ure.JPG

• http://upload.wikimedia.org/wikipedia/commons/thumb/1/15/Rockslide_at_Oddicombe.jpg/800px-

Rockslide_at_Oddicombe.jpg

• http://upload.wikimedia.org/wikipedia/commons/4/42/Rock_slide.jpg

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Citations Cont.[#2] (in order by slide)

• http://upload.wikimedia.org/wikipedia/commons/c/cb/Misaki_Stratum_Slump_Structur

e_2013-03.JPG

• http://s0.geograph.org.uk/geophotos/02/27/31/2273175_d8bb4209.jpg

• http://upload.wikimedia.org/wikipedia/commons/6/63/Slide-guerrero1.JPG

• http://t3.gstatic.com/images?q=tbn:ANd9GcTWxhOEtzWKMP1Hkk-

whSSzsxilpkJzZK9OqPgodT_MQkSZAREfJg

• http://upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Home_sunk_by_mud_flo

w.JPG/1024px-Home_sunk_by_mud_flow.JPG

• http://s0.geograph.org.uk/geophotos/01/40/58/1405853_fa82c7e8.jpg

• http://upload.wikimedia.org/wikipedia/commons/0/0e/Soil_Creep,_Millennium_Hill_-

_geograph.org.uk_-_518574.jpg

• http://s0.geograph.org.uk/geophotos/02/09/15/2091548_7454d853.jpg

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