Hi I am Jared welcome to Fun Science Demos.
The big idea today is erosion and how water has the power to shape our land.
But we do not want the water to shape our land too much
because we need that soil to grow plants.
We use those plants for food and animals use those plants for food.
So what you see in front of me are three different types of land.
This first type is just bare soil.
It is just soil.
This next type has dead leaves on top
and the third type has plants growing in the soil.
This may not look too exciting right now but when it rains
that water has the power to change the land.
And we are going to make it rain
to see what that water is going to do to our land.
So we cut the top off of three plastic bottles
and we put the same soil in each of those three bottles.
All of these bottles have the same soil.
We covered this soil with dead leaves and we grew some plants in this bottle.
We have also used other plastic bottles to catch the water that is going to come out of these
when we pour it into the bottle.
We want to pour water into each bottle and see what happens.
Does that water have the power to change the land?
What do you think is going to happen when we pour water into this bottle and it comes out into the cup.
Will it be any different from the water we pour into this bottle as it comes into the cup?
And will this one be any different when we pour water into this bottle
and it comes out into this cup?
So I am going to slowly pour water in you are going to see the water level rise
and we will see what happens with our soil.
We will keep it coming and now it is coming out.
Take a look at the bottle used to catch the water.
What do you notice?
Well it is cloudy.
So why is it cloudy?
That is because all the dirt in the soil from our bottle was washed into the cup.
The water had the power to actually take the dirt and the soil with it out of the bottle and into the cup.
The water moved the soil.
It shaped the soil.
So now I am going to pour about the same amount of water into the next bottle.
What do you think is going to happen?
The water that we catch will be just as dirty.
Will it be less dirty?
Will we even be able to see a difference?
Well let us pour the water and find out.
Here we go.
So I am pouring the water in making it rain
adding water to our bottle.
I can see the leaves floating to the top.
Do we have any overflow? Yes we do.
Stop the rain and see what we have
So we have zoomed in so you can compare the two.
This one has a lot of the soil in the container.
This one just has a little bit of the particles a little bit of the soil in that water.
So why do you think this container is a little bit cleaner?
What is different between the two?
Well this one had leaves dead leaves on top and I think
most of these dead leaves helped protect the soil underneath from moving with the water.
So what do you think is going to happen with our third container?
We have plants growing in the soil.
What is going to happen when we add water and make it rain in this container?
Alright here we go.
Let us the water about the same amount.
Pouring the water in...
What do you think is going to happen here?
Add a little bit more.
it is coming out.
We are going to stop pouring and see if we can compare what we see coming out
The water coming out of this container looks a whole lot cleaner than this one and a little bit cleaner than this one
So the question is why.
Why is this water cleaner I poured about the same amount of water into each
container of soil but this one looks really clean?
Well to answer the question why we have to zoom in and take a closer look
at what is really going on here.
So now we are all set to take a closer look at why the
water coming out of this bottle was so clean and clear compared to the others.
To do that I am going to actually lift these plants out of this bottle and let us see what happens.
What I notice right away is what comes along with all of the plants.
Well the soil is actually coming out too.
When I flip it over I think you will be able to see why.
So we have zoomed in so we can see what is going on here.
Why is this soil staying together why is it staying in place?
Well you can see the roots from our plants grew into the soil and almost
like little fingers those roots are holding the soil together.
So when it rains the roots keep the soil from washing away.
The roots of the plant that is what keeps the water from eroding the soil.
Besides holding the soil together and in place roots do another amazing thing.
To show you that I am going to squeeze this and I want you to watch what happens.
Where did all that water come from?
Well that came from when we made it rain on our soil.
The roots of the plants helped hold that water in.
Plant roots actually go deep into the soil and this model is going to help us see how deep they can go.
We are going to zoom in and see if we can see those really
tiny plant roots that we have growing in our soil.
We have zoomed in now so you can see these tiny roots in action.
I am going to point them out and they actually extend from the plant all the way down to the bottom of our soil.
I will point out some of the bigger ones.
They grow down into the soil.
And think about what they are doing.
They are holding that soil in place.
All of these tiny roots getting nutrients from the soil but they are also helping the soil out.
Plants do an amazing job at keeping erosion from washing away too much soil.
We need that soil we depend on that soil to grow plants.
And animals depend on that soil to grow plants.
If you want to learn more about plants and soil and erosion
check out our links in the video description.
Science is so cool and sometimes it is dirty.
Thanks for watching!