Erosion Lab
Ally, Victoria, Hannah, and Mercedes
Introduction:
The soil erosion lab is preformed to determine how we can reduce run off and if grass will help
erosion. Runoff is when water or other liquids are going down into a stream, lake, ocean, etc. Runoff is a
problem because when the water goes to these places it does not just go by itself. Soil, chemicals and
other substances are running off as well. These things are harmful to the places it is taking them but it
can also be harmful for where they are leaving. Soil erosion is when there is no vegetation to hold it in
place and it erodes with the water. Harmful effects to the land and animals can come from erosion, the
land will be left barren and destroyed, animals will have no land to feed from and their water might be
poisoned due to chemicals and such in the water. All around erosion is a bad thing and we are trying to
see how we can help and prevent these problems.
Hypothesis:
I think that the bottle with the grass will have the least runoff and produce the clearest water quality.
Parts of the Experiment:
Experimental- bottle with grass, bottle with packed soil.
Control- bottle with soil
Independent Variable- quality of water
Dependent Variable- Amount of soil collected
Control Variable- Amount of water (150 mL), angle of bottle (45 degrees), time (1 min)
Supplies:
3- 2 liter bottles with soil and side cut open
Grass in one bottle
3 beakers
3- 150mL of water (150 per bottle)
Ruler
Timer
Procedures:
1) Plant grass seeds in a two-liter bottle cut in half and let grass frow for two months
2) Fill one two liter bottle cut in half with loose soil and the second tow-liter bottle cut in half with
compacted soil
3) Measure out 150mL of water into three beakers
4) Take one two-liter bottle and tilt it to a 45 degree angle. To check this make sure the end of the
bottle is 9 inches off the table while the front of the bottle is resting on top of the 250mL
beaker, making a 45degree angle with the beaker.
5) Pour 150 mL of water on top of the soil and start the timer right when you start pouring for 1
minute.
6) The water will run into the beaker with soil, measure the amount of water that falls into the
beaker and look at the water quality.
7) Repeat for the other two bottles
Data & Analysis:
Bottle type
Bottle 1
Description
Loose soil
Bottle 2
Compacted soil
Bottle 3
Grass
Quality of water
Sediment, yellow,
cloudy, few soil clumps
Black, least runoff, most
erosion, huge soil
chunks
Clear, few soil chunks,
most runoff, least
erosion
Amount of runoff
80 mL
30 mL
125 mL
The data table shows us that bottle 3 with the grass had the best quality of water. The grass
helped to purify the water but there was still a lot of runoff. Bottle 2 had the least runoff but the most
soil erosion. The soil eroded because there was nothing for it to cling to and stay on the soil, the water
washed it away. Bottle 1 was the loose soil and that was the medium of the group. There was not too
much runoff and the water was not to dirty but it still was not as clean and erosion free as it could be.
Conclusion:
This lab has successfully determined which type of soil would have the best water quality and
least erosion. The Bottle (3) with the grass had the best water quality and the least erosion. The grass
helped to hold the soil in place when the water came through. Just that little bit of grass kept the soil in
place, which led to the water being cleaner and the soil staying. When grass or other vegiation is gone it
is hard for the soil to stay in place and stand up to the water. We can see that in our lab, the best thing
for erosion is for there to be something in the soil like grass. This will naturally purify the water going
into the steams or lakes and it keeps your land in tack.
There are many instances that can cause erosion, one is over grazing. Animals come and eat the
grass and plants from the ground and leave nothing but the soil. If this happen to long it will cause there
to be nothing holding the soil. The soil will then be taken by rain or other water into a possible stream,
or body of water. If the riparian areas of the land are not up kept and left alone, the water will not be
filtered and the soil will go in. This is just one example of erosion and it is so easy to prevent, but once it
has happened it is hard to go back so it is important to start now and protect the land.
Citations:
Vidal, John. "Soil Erosion Threatens to Leave Earth Hungry." The Guardian. N.p., 10 Dec. 2010. Web.
<http%3A%2F%2Fwww.theguardian.com%2Fenvironment%2F2010%2Fdec%2F14%2Fsoil-erosionenvironment-review-vidal>.