1.1 The Environment
The word environment is derived from a French word ‘Environner’, which means to encircle or
surround. Environment can be defined as the sum total of external factors, substances and
conditions which influence organisms. Environment is usually divided into two parts.
• The physical environment consists of forces of nature like wind, gravity, conditions like
temperature and light, time, and non-living materials like soil and water.
• The biotic environment is made of all living beings including their reactions, interactions
and interrelated actions. Any constituent or condition of the environment which affects
directly or indirectly the form of functioning of the organism in any specific way is called
environmental factor or ecological factor.
It is universally accepted that environment creates favorable conditions for the existence and
development of living organisms. The environment for any living organism has never been
constant or static. It has always been changing sometimes slowly and sometimes rapidly or
drastically. Like other organisms, man is also affected by his environment and these changes in
environment may benefit or harm him. Thus, we can say that every living species of plants or
animals influence its environment and in turn gets influenced by it.
Since the ancient times, man started interfering with the environment; he devastated forests by
cutting down trees for the wood and for other household needs. He removed stretches of forests
for bringing land under cultivation. He killed the animals; the gentle ones for blood and the
fierier ones for safety. He has polluted rivers with chemicals from factories, thereby making the
water unfit for his needs. All these activities however did not affect the environment too
seriously up to a fairly long time because population was not too high and life style was not so
complex.
No country in the world can build a brick wall around its air, so if the air pollution occurs in one
part, it is likely to affect another part of world. And who is to blame for all this; certainly the one
and the only man who has actively damaged and polluted the environment, thereby interfering
with natural processes and trying to twist them to his advantage.
