Soil Video Lecture - Class 8

learning about soil teeming with life
soil teeming with life soil is one of
the most important natural resources it
supports the growth of plants by holding
the roots firmly and supplying water and
nutrients
it is the home for many organisms like
earthworm snail snakes and rat soil is
essential for agriculture agriculture
provides food clothing and shelter for
all oil is inseparable part of our life
there are different sources from where
we find different variety of soil garden
soil we find plants and grass are grown
it is home for ants earthworm etc garden
soil is moist and the soil is for tile
their soil from the roadside is
different from the garden soil the soil
which is lying on the roadside is dry
and not so fertile you find some
unwanted weeds growing over there
soil from the area where construction is
going on is a mixed soil it is a mixture
of sand stones samam etc information
bulletin bags and plastics pollute the
soil they also kill the organisms living
in the soil that is why there is a
demand to ban the polythene bags and
plastics soil profile soil is composed
of distinct layers let us perform the
following activity to find how these
layers are arranged tivity take a little
soil break the clumps with your hand to
powder it now take a glass beaker 3/4
filled with water and then add a handful
of salt ooh it hurt well with the stick
to dissolve the soil
now let it stand undisturbed for some
time
soil is formed by the breakdown of rocks
by the action of climate water and wind
this process is called weathering a
vertical section through different
layers of soil is called the soil
profile each layer differs in feel
texture color depth and chemical
composition these layers are referred to
as horizons we see five layers of
particles of different sizes in the
glass tumbler on the first layer it is
houmous the rotting dead matter floating
in the soil is called
Yuma's second layer it is water on the
third it is clay on the fourth layer it
is sand and on the fifth layer it is
gray will usually see the top surface of
the soil not the layers below it if we
look at the sides of a recently dug
ditch we can see the inner layers of the
soil - such a view enables us to observe
the soil profile at that place soil
profile can also be seen while digging a
well or laying the foundation of a
building upon most horizon is generally
dark in color as it is rich in humors
and minerals the houmous makes the soil
fertile and provides nutrients to
growing plants there is generally soft
porous and can retain more water it is
called the topsoil or the a horizon
provide shelter for many living
organisms such as
worms rodent molt and beetles the roots
of small plants are embedded entirely in
the topsoil clear has a lesser amount of
Hemus but more of minerals this layer is
generally harder and more compact and it
is called the B horizon or the middle
layer third layer is the C horizon which
is made up of small lumps of rocks with
cracks and crevices below this layer is
the bedrock which is hard and difficult
to dig with a spade
hurry soil is important for life on the
earth soil profile is a section through
different layers of soil various layers
are called horizons as of different
types clay loam E and sandy that is all
in this topic students
let us discuss more in the next topic
till then enjoy learning