Soil is one of the most important components of the Earth. It
is essential for food-growing, building etc. It takes a long time
to form, but it can be damaged very fast because people dont care
for it. A lot of elements ruin soil. One of these elements is
erosion
Slide 3
Erosion is a process of discomposure and transporting of
elements on the Earth. (e.g. soil, rock, minerals). External
effects make erosion, e.g. abnormal rainfall, slope and structure
of the soil (type, class), quantity of vegetation etc.
Slide 4
A B Soil before erosion Discomposure after erosion
Slide 5
There is a few types of erosion in the world. Erosion caused by
water, glacier, wind, We are going to talk about two types of
erosion.
Slide 6
Water erosion water takes away small elements of the soil
Slide 7
Wind erosion rocks are discomposured by elements which wind
takes away
Slide 8
Bad ploughing countenances erosion. When the furrows are
straight down the hill, they can not hold back the water which
flows down to villages and overflows roads. Sludge can flow to
cellars and make harm.
Slide 9
Stock raising on slope can cause erosion too. Cows feed off
grass. Water isnt held back by grass and flows down the slope.
There are a lot of problems with erosion (e.g. new houses, new
roads, ).
Slide 10
The best protection from erosion is forest planting. Tree roots
peen the ground layer, other plants seep water.
Slide 11
This experiment shows consequences of bad ploughing. We
prepared a plastic plate and we put small quantity of soil on it.
We spread soil on it and we used a sprayer for wetting the soil. We
made a line of horizontal furrows and a line of vertical furrows.
Then we underlayed one side of the plate. We used the sprayer and
we made rain. We watched what the water was doing in different
cases. So the way of the ploughing is very important.
Slide 12
Click on video to start and stop playing... 1 3 2 4
Slide 13
In this video you can see water erosion. The water was poured
out from a field. It was caused by bad ploughing.
