why soil differ from place to place

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HOW DOES SOIL DIFFER FROM PLACE TO PLACE?

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Page 1: why soil differ from place to place

HOW DOES SOIL DIFFER FROM PLACE TO PLACE?

Page 2: why soil differ from place to place

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: why soil differ from place to place

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: why soil differ from place to place

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.

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Page 5: why soil differ from place to place

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- 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: why soil differ from place to place

- 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: why soil differ from place to place

Do you know that

the soil have

layers?

Really? Let’s dig it & find out

the soil layers.

Page 8: why soil differ from place to place

Layers of the soil

Sub soill

Weathered bed rockl

Bed rockl

“Rock soil”

Top soil

Page 9: why soil differ from place to place

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: why soil differ from place to place

2- Sub soil

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

Page 11: why soil differ from place to place

3- Bed rock

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

Page 12: why soil differ from place to place

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: why soil differ from place to place

Types of the soil

Sand soillSilt soill

Clay soill

Page 14: why soil differ from place to place

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: why soil differ from place to place

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: why soil differ from place to place

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.