ShareRocks and Soils - You've Got What I Need!
Lunch Time
Have you ever thought about where the food you eat at
lunch comes from? Do you think about how much water it takes to grow your
food? Farmers do. It takes a lot of water to grow food.
Think about
it!
Crops use a lot of water. Listed below are just a few examples.
| Food item (one serving) |
Water required (Gallons) |
|
| Tomato | 3 | 
|
| Lettuce | 6 | 
|
| Potato | 6 | 
|
| Apple | 16 | 
|
| Orange | 22 | 
|
| Corn | 61 | 
|
| Watermelon | 100 | 
|
The Soil-Water Connection
Research each crop above and list a country it is grown
in. Which of the above listed food is most produced in Utah? You have
probably seen commercials on television about conserving water. After
all, we do live in the desert and we do not have a lot of water to spare.
It is important for all of the people in Utah to conserve water, but it
is even more important for farmers in the state to use water wisely. Growing
food in Utah uses 87% of our water resources. Because water is limited
in Utah, farmers have to make sure that they have the type of soil where
water can readily be absorbed and stored. It is important that there is
plenty of organic material in the soil. Not only do crops get the nutrients
they need to grow and thrive from organic matter, but nutrients also act
like a sponge, helping the ground to store more water. Nutrients also
help to prevent erosion and produce more productive crops. When organic
matter is used up, soil packs together in clods. Soil without clods has
fewer air spaces. A soil with more organic matter is more crumbly. Not
only do crumbly soils take in water faster than soils with clods, but
they also hold more water. This increase in the water-holding capacity
of soil means that there will be less erosion. The ability for soil to
store water also helps make flooding less severe.
Just checking!
Imagine you are dirt. If you were dirt and you wanted
to be good dirt, would you be a crumb or a clod? To find out if you are
correct, highlight the box below.
The correct answer is a "Crumb." Good job! |
You're the scientist!
In this activity you will find out how soil
from your own garden affects the flow of water. You will determine if
you have "crumbly" or "cloddy" soil.
Materials:
- Large plastic lid (the type you would find covering a tub of margarine )
- Large plastic cup or styrofoam cup
- Piece of cheesecloth (You can get this from any hardware store.)
- Jar
- Measuring cup
- Rubber band
- Straight pin
- Scissors
- Watch with a second hand or timer
- Soil sample (about 250 ml - one cup)
Procedure:
- Use the pin to make several holes in the bottom and around the lower part of the cup. Since you may be doing this experiment individually and comparing your results to the rest of the class, make sure that you make the same amount of holes in the cup.
- Put the cheesecloth around the bottom of your cup and secure it with the elastic.
- Using scissors, cut a hole in the plastic lid. Make the hole just big enough for the bottom of the cup to fit inside. Be very careful using scissors!
- Fill the cup half full of your soil.
- Place the lid and cup over the jar.
- Pour 125 ml (one half cup) of water into the cup.
- Record the time that the water was poured into the cup.
- Record the time that you first observed the water dripping from the bottom of the cup
- After thirty minutes, remove the cup from the jar and measure and record the amount of water in the jar.
- Compare and share your results with your classmates.
Analysis:
- What did you find out from doing this activity?
- Look at your soil. Does it seem to have a lot of organic material in it?
- Get your hands dirty. Take a small amount of your soil and press it together. Is it cloddy or crumbly? If it is cloddy, what could you do to make your soil more crumbly?
