The Scoop on Soil

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• The Scoop on Soil

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Of What is Soil Made?

• sand
• rocks
• dried plants
• dead organisms
• water
• air

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Soil Stacks Up
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What are Some Processes that Form Soil?

• Decay of plant matter
• Settling of volcanic ash
• Transport by rain, streams, and rivers
• Deposition of sediments in rivers and lakes
• Weathering
• Erosion

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Decay of Plants
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Settling of Volcanic Ash
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Transport by Rain
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Deposition of Sediment
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Weathering

• http//video.yahoo.com/watch/1794281/5931740

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There are Two Main Types of Weathering

• Mechanical
• Chemical

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In the next 7 slides, try to determine what
caused the weathering.
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Erosion

• http//video.yahoo.com/watch/1794382/5933084

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Erosion from Gravity
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Erosion by Wind
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Erosion by Water
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Erosion by Ice
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Whats good about erosion?

• New soil is formed. Erosion results in deposits
  of dark, fertile soil, perfect for growing crops.
• Erosion reveals marvels of nature such as
  mountains, sandstone arches, and polished cliffs.
• Without erosion, rock debris would simply pile
  up.
• Soil erosion may slow down global warming by
  carrying carbon into wetlands where it is stored
  for long periods of time. (theory)

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Whats bad about erosion?

• Land can be stripped of soils needed for food to
  grow.
• Landslides can destroy whatever is in their
  paths.
• Rivers can be filled with silt, disrupting their
  ecosystems.
• Erosion causes cracks, gaps, and ditches in the
  landscape.
• When soil erodes, it cannot support many types
  of plant life.

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What can be done to prevent erosion?

• Plant trees and bushes along riverbanks to hold
  soil in place.
• Plant trees that will block the wind.
• Use careful, smart farming practices that wont
  disturb topsoil.
• Use common-sense approaches to construction, such
  as dont build on steep slopes.
• When hiking, stay on trails.

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Review
1. What is weathering?

• Answer Weathering is breaking down rock into
  pebbles and sand by physical or chemical
  processes.

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2. Give at least three examples of weathering
processes.

• Answer Wind, water, ice, heating, cooling, acid
  rain.

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3. What is erosion?

• Answer Erosion is the movement of Earth
  materials by processes such as wind, water, ice,
  and gravity.

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4. Explain how the formation of soil is related
to weathering of rock.

• Answer Rocks are broken into small pieces by the
  process of weathering. Then the small particles
  become part of the soil.

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5. How does deposition of sediments relate to
soil formation?

• Answer As sediments fall to the bottom of rivers
  and lakes, they build up deposits to form soil.

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6. Name at least two forces that cause erosion.

• Answer Wind, water, gravity.

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7. What is soil?

• Soil is the thin living skin that covers the
  land. It goes down into the ground just a short
  way. Soil is more than rock particles. It
  includes all the living things and the materials
  they make or change. Soil is a precious resource
  that sustains life on earth.

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8. Name at least three layers of soil.

• Organic layer, topsoil, subsoil, rock

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9. What can you personally do to help prevent
erosion?

• Plant trees and bushes along riverbanks to hold
  soil in place.
• When hiking, stay on trails.

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What process causes landslide erosion?

• gravity

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Credits
The Rock Cycle http//www.geolsoc.org.uk/rockcycle
Soil Forming Factors http//soil.gsfc.nasa.gov/so
ilform/parmat.htm Dirt The Scoop on Soil
(Amazing Science) Paperback Rosinsky, Natalie M
(Author) The Open Door Website
http//www.saburchill.com/lab/field/field02.html S
oil Profile http//library.thinkquest.org/J003195F
/newpage5.htm Soil is not dirt
http//www.wsu.edu/gened/learn-modules/top_agrev/2
-soil/soil1.html The Dirt on Soil
http//school.discoveryeducation.com/schooladventu
res/soil/down_dirty.html What is soil?
http//www.blogdivvy.com/growing-vegetables/what-i
s-soil.htm Geography4Kids.com http//www.geography
4kids.com/files/land_weathering.html Tree Hugger
http//www.treehugger.com/files/2008/08/greenland-
crack-up.php  Deadly Landslides in Guatamala
http//www.guardian.co.uk/world/gallery/2010/sep/0
6/guatemala-landslides Wikipedia Weathering and
Soils http//www.iamtonyang.com/0407/oak_leaves.jp
g Soil Forming Factors http//soil.gsfc.nasa.gov/
soilform/deposits.htm How Stuff Works
http//science.howstuffworks.com/dictionary/petrol
ogy-terms/volcanic-ash.htm North Coast Journal
http//www.northcoastjournal.com/011603/cover0116.
html Just the facts http//www.cfact.org/a/765/Eco
logical-benefits-of-soil-erosion