Under Your Feet

(Nora) #1
9

45%


20-30%


Air

Organisms live and grow best in

soils with almost equal amounts of

air and water, which they need to

survive. Air moves through the soil

in cracks, burrows, and pores.

Minerals

A mineral is a solid that is found

naturally and made of crystals. In soil,

the gritty mineral ingredient includes

particles called sand, silt, and clay.

Some plants grow well in sandy soils,

but others prefer soils with lots of

clay particles.

Beetles begin their lives

underground, where they

need air to breathe.

Centipedes take

in air through

holes along

their bodies.

S

a
n

d

p

a

r

t

i

c

l

e s c a n b e 1

,

0

0

0
tim

e

s

b

i

g

g

er

tha
n

c
l

a

y

.

Turnips grow well

in loose, sandy soils.

Soil minerals are

worn away from

rocks on the surface

and from bedrock.

S

il
t

S

a

n

d

B

e

d

r

o

c

k

C

l

a
y

I

n

o

v

e

r

l

y

w

e
t
s

o

i

l

s

,

w

a

t
er

f

i

l

l

s

a

i

r

y

s

p

a

c

e

s

.

008-009_The_stuff_of_soil.indd 9 08/11/2019 09:

Free download pdf