Weathering and erosion slowly change rocks and landforms over time. Weathering occurs through physical and chemical processes that break down rock and soil. It is influenced by climate, water, plants, and animals. Erosion is the process by which soil and rock are removed and transported. Over many years, this forms new soil layers and landscapes. Conservation methods like contour farming and cover crops can help reduce soil erosion.

1. Effects of
Weathering and
Erosion
Copyright: Kella Randolph B.S., M.Ed.
A dirt road is covered with soil eroded from the higher land above.
https://i.stack.imgur.com/op7id.jpg
Wind, rain, heat and cold cause rocks to "weather". Over time, this wears away
parts of the rock and changes the shape. http://opengeology.org/textbook/wp-
content/uploads/2016/07/MB2.jpg

2. Weathering
Weathering is the breaking down of rocks, soils
and minerals as well as artificial materials
through contact with the Earth's atmosphere,
biota and waters.

3. Weathering by frost wedging
Extreme temperature changes, and water freezing in cracks caused
this boulder to split.
https://upload.wikimedia.org/wikipedia/commons/3/3d/Shattered_boulder_on_S
gurr_nan_Gillean_-_geograph.org.uk_-_618629.jpg

4. Mechanical weathering
mechanical weathering is a physical
process.

5. Water weathered tree
https://get.pxhere.com/photo/tree-nature-forest-grass-rock-branch-plant-wood-sunlight-leaf-flower-travel-log-spring-
green-jungle-autumn-weather-botany-flora-season-thailand-crash-weathered-background-woodland-habitat-morsch-withers-
dry-wood-natural-environment-woody-plant-1034837.jpg

6. How is a plant or animal an agent
of mechanical weathering?
Plants and animals are agents of mechanical weathering. The seed of a tree may sprout in
soil that has collected in a cracked rock. As the roots grow, they widen the cracks, eventually
breaking the rock into pieces. Over time, trees can break apart even large rocks. Even small
plants, such as mosses, can enlarge tiny cracks as they grow.
Animals that tunnel underground, such as moles and prairie dogs, also work to break apart
rock and soil. Other animals dig and trample rock aboveground, causing rock to slowly
crumble.

7. Biological
weathering
Roots
growing
into
rock
https://images.squarespace-cdn.com/content/59c3bad759cc68f757a465a3/
1518185902522-78319T68W8SRJA2F0AP2/Biological_weathering%2C_Harrison_Rocks
_-_geograph.org.uk_-_71562.jpg?content-type=image%2Fjpeg

8. Animals
burrow
Badger

9. Erosion
Erosion is the process by which soil and
rock are removed from the Earth's
surface by natural processes such as
wind or water flow

10. Erosion
by wind
Erosion by waterhttps://upload.wikimedia.org/wikipedia/commons/t
humb/0/09/Durdle_Door_-_geograph.org.uk_-
_55738.jpg/500px-Durdle_Door_-
_geograph.org.uk_-_55738.jpg
https://upload.wikimedia.org/wikipedia/commons/d/
d9/Dust_Storm_Texas_1935.jpg

11. Leaching
Leaching is the process of extracting
minerals from a solid by dissolving
them in a liquid

12. Water has leached minerals from the tleached zone.
https://alpandino.org/en/course/15/15c/podzolization.jpg

13. Rain water is slightly acidic
Rain water is slightly acidic because
Carbon dioxide forms carbonic acid
when mixed with water

14. Rain washes the forest
https://a1gaurav.files.wordpress.com/2011/06/its-raining2.jpg

15. Major factors involved in how
fast weathering occurs
Climate, mineral composition,
amount of water

16. http://1.bp.blogspot.com/-V1748xphwI8/UMRn83Bq_fI/AAAAAAAAAgw/TtrGR_sW5js/s1600/seasons.jpg
Autumn Winter
Spring
Summer

17. Weather causes many changes
http://1.bp.blogspot.com/-13P2RCfBNOY/U2f3kiAxPoI/AAAAAAAAAX0/IWSdDqE5tls/s1600/natdis.jpg.jpg

18. Soil Horizons
The layers in a soil profile are called
horizons

19. Soil horizons
Soil is older at lower levels.
Weathering breaks the lower parent
rock and the newer levels are formed
above it. The top layer is richer and
with organic matter and water, can
support plant life.
https://lh6.googleusercontent.com/-SEX6s48FtDg/TqC0Pu7z_-
I/AAAAAAAACWs/Apg3MA_sJNs/s1600/soil_horizons.gif

20. soil and climate related
Warmer temperatures and high rainfall
increase rate of soil formation. Cooler
temperatures and less rain slow it
down.

21. Warm temperature, good soil and ample rain
create good conditions for plant growth.
This Photo by Unknown Author is licensed under CC BY-SA
https://upload.wikimedia.org/wikipedia/commons/c/c6/PLSP_Memories_of_Green.jpg

22. Soil, climate, water wind, hours of sunlight and more all affect the
fertility of an area.
https://martinhumanities.files.wordpress.com/2015/09/slide-1-728.jpg

23. Dry , hot areas with constant winds do not encourage plant growth
https://i.stack.imgur.com/5Ytrw.jpg

24. Conserve soil
Some ways to conserve soil are
Contour farming/shelter belts, cover
crops, and strip crops.

25. Shelter belt
(right) Hedges and lines of trees
slow the wind and allow plants to
grow.
Contour farming
(left)By channeling the water in
curved rows, the water is slowed
and this allows more time for it to
soak into the ground where the
plants are growing. It also helps
prevent soil from washing away.https://c2.staticflickr.com/8/7165/6549218585_6aedb9ed
3d_s.jpghttps://c2.staticflickr.com/8/7165/6549218585_6a
edb9ed3d_s.jpg
https://www.ag.ndsu.edu/food/efnep-snap-ed/GPTPC/events-1/great-plains-tree-pest-
council-meeting-minutes-and-documents-1993-2006/images/pembina-and-cavalier-
county-conservation-and-farmstead-planting-photo_aerial-survey-2013_071.jpg

26. Cover crops
such as clover, hold the
soil in place and create
new nutrients for the
soils
Strip crops
(left)
Help to use different minerals
for growth and after harvest,
the plants are plowed back into
the soil, causing more nutrients
to form for future use.
https://malvedos.files.wordpress.com/2010/12/cover-crops-bee-
heaven.jpg
https://c2.staticflickr.com/6/5291/5412456421_b187f352ff_z.jpg

27. Thank you
for viewing