how does soil affect living things

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HOW DOES SOIL AFFECT LIVING THINGS?

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Page 1: How does soil affect living things

HOW DOES SOIL AFFECT

LIVING THINGS?

Page 2: How does soil affect living things

WHY DO YOU THINK SOIL IS IMPORTANT?

-Soil is very important for all living things.

- It’s important for plants to grow.

-Humans need it to plant different fruits & vegetables.

Page 3: How does soil affect living things

Have you ever

wondered how is the

soil formed?

My mum told me it is formed by nature.

By nature? How?

Well, let me show you how.

Page 4: How does soil affect living things

How is the soil formed?

-Rocks can change because of the changes in the weather, like rains & storms & wind.- After a long time, rocks can break into small pieces.- These small pieces are called weathered rocks , they make a part of the soil.

1

Page 5: How does soil affect living things

2

- Also when animals & plants die, and we bury them under the ground, after many years they start to decay & break down,, so they also make up a part of the soil.

Page 6: How does soil affect living things

- The soil is made of a mixture of

What’s the soil made of?

Weathered rocks

Humus Minerals

- They are formed when the rocks break down into small pieces because of the weather changes.

- When animals & plants die & we burry them under the ground, they break down & decay, this is: Humus

- They are the nutrients that plants need to grow.

Page 7: How does soil affect living things

Do you know that

the soil have

layers?

Really? Let’s dig it & find out

the soil layers.

Page 8: How does soil affect living things

Layers of the soil

1 -Top soill

2 -Sub soill

3 -Bed soill

(Sub = Under)

“Rock soil”

Humus

“Humus is present in the top soil layer”

Page 9: How does soil affect living things

1- Top soil

-It is the top layer of the soil.- It’s dark in color.-The humus & minerals are found in this layer.

Page 10: How does soil affect living things

2- Sub soil

-It is under the top soil.- It’s lighter in color than top soil & has less humus.

Page 11: How does soil affect living things

3- Bed soil

-It is the lowest layer of the soil below the sub soil.-It is called: rock soil

Page 12: How does soil affect living things

Where do you

think cactus

plant can grow?

It grows in the desert, in the

sand

Do you think

flowers can grow

too in the sand of

the desert?No, flowers

needs another type

of soil to grow

Page 13: How does soil affect living things

Types of the soil

Sand soillSilt soill

Clay soill

Page 14: How does soil affect living things

Sand soill

- The size of the particles of sand are large.

- There is too much air space between the sand particles, so water passes fast & it holds very little amount of water.

Particles

-It is dry soil.

Page 15: How does soil affect living things

Silt soill

- The size of the particles of silt are smaller than the sand.

- There is less air space between the silt particles, so water passes slowly .

Particles

Page 16: How does soil affect living things

Clay soill

- The size of the particles of silt are very small “Cannot be seen by your eyes”.

- There is no air space between the clay particles, so water doesn’t pass & the clay holds lots of water inside it.

Particles

- It’s wet soil.

Page 17: How does soil affect living things

Loaml

-It is made of sand, silt & clay together.

+ + =

- It’s not so wet & not so dry.

- Plants grow best in this soil.

Page 18: How does soil affect living things

Protecting the soil

- Soil is a natural resource that is necessary & useful to people.

Without soil

- Plants will not grow, so we will have fewer medicine.

- People & animals will not find food to eat.

- There will be no cotton to make clothes or wood to make builings.

Page 19: How does soil affect living things

How can we

protect our soil?

First, we have to keep the soil clean

Second, We have to put nutrients for

the soil to grow plants

well

Third, We have to prevent the soil damage,

so always water it &

keep it healthy