Science Behind Water
Abhinandan Bhardwaj PhD
One of the most
essential resources on Earth is water. Water is
the basic building block for all life on Earth,
without it no living thing can survive. Water is
the most plentiful natural resource on our
planet, That's why Earth is also called the
"water planet". From space it looks
predominantly blue, as 74 % of its surface is
covered by water. Oceans contain 97 % of the
earth's water while the remaining 3 % is
classified as freshwater. Seventy-seven percent
of this surface freshwater is stored as ice and
22% as groundwater and soil moisture. The
remaining freshwater, making up less than 1 % of
the world total, is contained in lakes, rivers
Water also helps
in regulating the temperature of the Earth. It
also helps in transporting essential nutrients
through the land, air, and all living things.
The flow of water through the atmosphere,
biosphere, lithosphere, and hydrosphere is
called the hydrologic, or water cycle.
Look what we do to the very scarce, extremely
Every year we dump, 14
billions pounds of sewage, sludge, and garbage into the world's
water bodies such as rivers, lakes and
streams all of which eventually end up in
the oceans. 19 trillion
gallons of waste also enter the water annually.
Fresh water is
becoming rare as its being plagued by more and
more human generated pollution every day. It has
been said that water will be "the oil of the
21st century," or "liquid gold," and that it
will cause wars between nations.
Main Causes of
As the world has industrialized and its
population has grown, the problem of water
pollution has intensified.
For many years, chemicals were dumped into
bodies of water without concern. While many
countries have now banned such behavior, it
continues to go on even today. Water pollution is
mainly caused by chemically treated and raw
sewage, waste from domestic farm animals and
industrial liquid waste. Other water pollutants
include pesticides, nitrates, phosphates, metals
such as copper, zinc, cadmium and mercury, and
chemical wastes including complex organic
compounds. In the sea, the majority of the
pollution is from rivers and coastal discharge,
some is from rainfall and some is as a result of
illegal dumping from ships and boats.
There are many
sources of water pollution, main two are as
Direct sources include industrial liquid
or solid waste released from industries,
factories, refineries, waste treatment plants
etc. Many developed countries including United
States, Canada and UK etc these practices are
illegal and heavily regulated but in many
developing contries the problem still exists.
Indirect pollution is when pollutants
enter the water source from contaminated soils,
rain water or ground water. Agricultural
practices contain residue such as fertilizers
and pesticides etc. which when leached can
pollute the both surface and ground water.
The effects of
water pollution are many fold
life on Earth, If fresh water is polluted it
leads to many short and long term fatal diseases
among animals and plants including humans.
Pollution of water can lead to:
a) Poisoning of
drinking water sources such as surface water (
rivers, lakes etc. and ground water.
b) Poisoning of water and food which animals eat
and then pollutants can gets accumulated in
animal's body. Such toxins are called
bioaccumulated toxins. When we eat meat of these
animals these toxins find its way to our bodies.
c) When Oceans, rivers and lakes gets polluted
they lead to destruction of oceans river and
lake water ecosystems.
d) Deforestation from acid rains etc.