how does soil affect living things
Post on 24-Jun-2015
1.519 Views
Preview:
TRANSCRIPT
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.
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.
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
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.
- 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.
Do you know that
the soil have
layers?
Really? Let’s dig it & find out
the soil layers.
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”
1- Top soil
-It is the top layer of the soil.- It’s dark in color.-The humus & minerals are found in this layer.
2- Sub soil
-It is under the top soil.- It’s lighter in color than top soil & has less humus.
3- Bed soil
-It is the lowest layer of the soil below the sub soil.-It is called: rock soil
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
Types of the soil
Sand soillSilt soill
Clay soill
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.
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
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.
Loaml
-It is made of sand, silt & clay together.
+ + =
- It’s not so wet & not so dry.
- Plants grow best in this soil.
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.
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
top related