2.  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 don‘t care for it. A lot of elements ruin soil. One of these elements is erosion…

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.

4. A B Soil before erosion Discomposure after erosion

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.

6. Water erosion – water takes away small elements of the soil…

7. Wind erosion – rocks are discomposured by elements which wind takes away…

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.

9.  Stock raising on slope can cause erosion too. Cows feed off grass. Water isn‘t held back by grass and flows down the slope. There are a lot of problems with erosion (e.g. new houses, new roads, …).

10.  The best protection from erosion is forest planting. Tree roots peen the ground layer, other plants seep water.

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.

12. Click on video to start and stop playing... 1 3 2 4

13.  In this video you can see water erosion. The water was poured out from a field. It was caused by bad ploughing.

16. Humpolec2008