Preventing Erosion

Science · Earth's Systems · ages 7-8

Name ______________________ Date ____________

Wind can never change the shape of land.
Circle one: True False
Which of these describes erosion?
- Wind and water slowly wearing away or moving land
- The land staying exactly the same forever
- Rocks growing bigger by themselves
Which of these is a solution people use to slow erosion?
- Digging up all the plants
- Planting grass and trees to hold the soil
- Pouring more water on the ground
A windbreak is a row of trees or a fence. How does it help stop erosion?
- It slows the wind down so it carries less soil away
- It makes the wind blow harder
- It has no effect on the wind at all
Look at the chart. Which one kept the most sand safe from the waves?
- No wall
- Plants
- Wall
A farmer wants to stop rain from washing soil off a hillside. Which solution would help most?
- Removing all the plants from the hill
- Planting deep-rooted plants to hold the soil
- Watering the hill more often
In a rain test, a bare slope lost 9 cm of soil, but the same slope with plants only lost 3 cm. How many fewer centimeters of soil were lost with plants?
Answer: ______________
Ravi says a wall and planting grass do the exact same job, so it does not matter which one you test. Is Ravi right?
- Yes, they always work exactly the same
- No, only walls ever work
- No, each solution works differently, so testing shows which fits the spot best

Answer key

For grown-ups. Fold this page away before handing over the rest.

False · Wind can pick up and move sand and soil bit by bit, slowly reshaping land over time.
Wind and water slowly wearing away or moving land · Erosion is wind or water slowly wearing away and moving bits of land.
Planting grass and trees to hold the soil · Roots from grass and trees grip the soil and help keep it in place.
It slows the wind down so it carries less soil away · A slower wind has less power to pick up and carry soil away.
Wall · The wall kept 8 cm of sand, more than plants (5 cm) or no protection (2 cm), because it blocked the waves directly.
Planting deep-rooted plants to hold the soil · Roots hold soil in place like a net, so rain has a harder time washing it away.
6 · 9 minus 3 is 6, so the plants kept 6 more centimeters of soil in place.
No, each solution works differently, so testing shows which fits the spot best · A wall blocks water directly while grass holds soil with roots, so testing both shows which truly works best for a place.