1. The Hydrosphere
“a river is more than an amenity… it is a treasure.”
-Oliver Wendell Holmes-

2. Hydrosphere
• Is a dynamic mass of liquid that
is continually on the move, from
the oceans to the atmosphere, to
the land and back again.
• The global ocean is blanketing
nearly 71% of the earth’s surface
and accounting for about 97% of
the earth’s water.

3. Hydrosphere
• Precipitation:
• Means falling from a height.
• Rain
• Snow
• Hail
• Sleet
• Mist

4. Hydrosphere
• Run-off
• Refers to the flow back to the
oceans of the precipitation that
falls on land.

5. Sources of fresh water
• Surface water
• Precipitation that does not
infiltrate into the ground or
return ton the atmosphere by
evaporation or transpiration.

6. Sources of fresh water
• Ground water
• It is the water that penetrates the
soil and reaches the water table.
• Zone of saturation
The area where all available
pores, spaces, or cracks in soil and
rock in the earth’s crust.

7. Sources of fresh water
• Water table
• Is the upper surface of the zone
of saturation.
• 40 times as much ground water
below the earth’s surface as
there is in all the world’s streams
and lakes.

8. Significant of Water
• The significant of water needs no elucidation. It is
as under:
(1) It is revealed by the history of human
civilization that water supply and civilization are
most synonymous.
(2) Several cities and civilizations have
disappeared due to water shortages originating
from climatic changes.
(3) Millions of people all over the world,
particularly in the developing countries, are losing
their lives every year from water-borne disease.

9. Significant of Water
(4) An understanding of water chemistry is the
basis of knowledge of the multidimensional
aspects of aquatic environment chemistry,
which involve the sources, composition,
reactions, and transport of the water.
(5) About 97% of the earth’s water supply is in
the ocean, which is unfit of the remaining 3%,
2% is locked in the polar ice-caps and only 1% is
available as fresh water in rivers, lakes,
streams, reservoirs and ground water which is
suitable for human consumption.