Shankar IAS
ENVIRONMENT
Notes
,COMPILATION FROM SHANKAR IAS ENVIRONMENT
PART-I-ENVIRONMENT ECOLOGY
CONTENTS
1. ECOLOGY
2. FUNCTIONS OF AN ECOSYSTEM
3. TERRISTRIAL ECOSYSTEM
4. AQUATIC ECOSYSTEM
5. ENVIRONMENT POLLUTION
6. ENVIRONMENT IMPACT ASSESSMENT
, ECOLOGY
defined "as a scientific study of the relationship of the living organisms with each other and
with their environment."
The classical texts of the Vedic period such as the Vedas, the Samhitas, the Brahmanas
and the Aranyakas-Upanishads contain many references to ecological concepts
The Indian treatise on medicine, the Caraka- Samhita and the surgical text Susruta-Samhita.
contain classification of animals on the basis of habit and habitat, land in terms of nature of
soil, climate and vegetation; and description of plants typical to various localities.
Caraka- Samhita contains information where air, land, water and seasons were indispensable
for life and that polluted air and water were injurious for health.
The environment is defined as 'the sum total of living, non-living components;
influences and events, surrounding an organism.
Components of Environment
1. Abiotic – Energy, Radiation, TEMP, Water, etc.
2. Biotic- plants, animals, man, DECOMPOSER ETC.
Diesel engine exhaust fumes can cause cancer, humans" and it belong to the same
potentially deadly category as asbestos, arsenic and 'mustard gases. World Health
Organization (WHO)
if a marine fish is transferred to a fresh water environment, it will not be able to
Survive.
Six main levels of organisation of ecology are:
1. Individual- Organism is an individual living being that has the ability to act or
function independently.
2. Population-Population is a group of organisms usually of the same species,
occupying a defined area during a specific time,
3. Community- Communities in most instances are named after the dominant plant form
(species). A community is not fixed or rigid; communities may be large or small.
Types of Community-
On the basis of size and degree of relative independence communities may be divided
into two types-
(a) Major Community
These are large-sized, well organized and relatively independent. They depend
only on the sun's energy from outside and are independent of the inputs and
outputs from adjacent communities.
E.g: tropical ever green forest in the North-East
(b) Minor Communities
These are dependent on neighbouring communities and are often called societies.
They are secondary aggregations within a major community and are not therefore
completely independent units as far as energy and nutrient dynamics are
concerned.
e.g: A mat of lichen on a cow dung pad.
, The environmental factors determine the characteristic of the community as well as the
pattern of organisation of the members in the community
The characteristic pattern of the community is termed as structure which is
reflected in the roles played by various population, their range, the type of area
they inhabit, the diversity of species in the community and the spectrum of
interactions between them
4. Eco-System-An ecosystem is defined as a structural and functional unit of
biosphere consisting of community of living beings and the physical
environment, both interacting and exchanging materials between them.
It includes plants, trees, animals, fish, birds, micro-organisms, water, soil, and
people.
When an ecosystem is healthy (i.e. sustainable) it means that all the elements live
in balance and are capable of reproducing themselves
Components of Ecosystem
The components of the ecosystem is categorised into abiotic of non-living and
biotic of living components. Both the components of ecosystem and environment
are same.
1. Abiotic Components
the inorganic and non-living parts of the world.
consists of soil, water, air, and light energy etc.
involves a ,large number of chemicals like oxygen, nitrogen-, etc. and physical processes
including volcanoes, earthquakes, floods, forest fires, climates, and weather conditions.
Abiotic factors are the most important determinants of where and how well an
organism exists in its environment. Although these factors
interact with each other, one single factor can-limit the range of an organism.
a) Energy
Energy from the sun is essential for maintenance of life. Energy determines the distribution of organisms in
the environment.
b) Rainfall
c) Temperature
Temperature is a critical factor of the environment which greatly influences survival of
organisms. Organisms can tolerate only a certain range of temperature and humidity.
d) Atmosphere
It is made up of 21% oxygen, 78% nitrogen , 0.038% carbon dioxide and other inert gases
(0.93% Argon, Neon etc).
e) Substratum
Land is covered by soil and a wide variety of microbes, protozoa, fungi and small
animals (invertebrates) thrive in it
f) Materials:
(i) Organic compound
Such as proteins, carbohydrates, lipids, humic substances are formed from inorganic
compound on decomposition.
ENVIRONMENT
Notes
,COMPILATION FROM SHANKAR IAS ENVIRONMENT
PART-I-ENVIRONMENT ECOLOGY
CONTENTS
1. ECOLOGY
2. FUNCTIONS OF AN ECOSYSTEM
3. TERRISTRIAL ECOSYSTEM
4. AQUATIC ECOSYSTEM
5. ENVIRONMENT POLLUTION
6. ENVIRONMENT IMPACT ASSESSMENT
, ECOLOGY
defined "as a scientific study of the relationship of the living organisms with each other and
with their environment."
The classical texts of the Vedic period such as the Vedas, the Samhitas, the Brahmanas
and the Aranyakas-Upanishads contain many references to ecological concepts
The Indian treatise on medicine, the Caraka- Samhita and the surgical text Susruta-Samhita.
contain classification of animals on the basis of habit and habitat, land in terms of nature of
soil, climate and vegetation; and description of plants typical to various localities.
Caraka- Samhita contains information where air, land, water and seasons were indispensable
for life and that polluted air and water were injurious for health.
The environment is defined as 'the sum total of living, non-living components;
influences and events, surrounding an organism.
Components of Environment
1. Abiotic – Energy, Radiation, TEMP, Water, etc.
2. Biotic- plants, animals, man, DECOMPOSER ETC.
Diesel engine exhaust fumes can cause cancer, humans" and it belong to the same
potentially deadly category as asbestos, arsenic and 'mustard gases. World Health
Organization (WHO)
if a marine fish is transferred to a fresh water environment, it will not be able to
Survive.
Six main levels of organisation of ecology are:
1. Individual- Organism is an individual living being that has the ability to act or
function independently.
2. Population-Population is a group of organisms usually of the same species,
occupying a defined area during a specific time,
3. Community- Communities in most instances are named after the dominant plant form
(species). A community is not fixed or rigid; communities may be large or small.
Types of Community-
On the basis of size and degree of relative independence communities may be divided
into two types-
(a) Major Community
These are large-sized, well organized and relatively independent. They depend
only on the sun's energy from outside and are independent of the inputs and
outputs from adjacent communities.
E.g: tropical ever green forest in the North-East
(b) Minor Communities
These are dependent on neighbouring communities and are often called societies.
They are secondary aggregations within a major community and are not therefore
completely independent units as far as energy and nutrient dynamics are
concerned.
e.g: A mat of lichen on a cow dung pad.
, The environmental factors determine the characteristic of the community as well as the
pattern of organisation of the members in the community
The characteristic pattern of the community is termed as structure which is
reflected in the roles played by various population, their range, the type of area
they inhabit, the diversity of species in the community and the spectrum of
interactions between them
4. Eco-System-An ecosystem is defined as a structural and functional unit of
biosphere consisting of community of living beings and the physical
environment, both interacting and exchanging materials between them.
It includes plants, trees, animals, fish, birds, micro-organisms, water, soil, and
people.
When an ecosystem is healthy (i.e. sustainable) it means that all the elements live
in balance and are capable of reproducing themselves
Components of Ecosystem
The components of the ecosystem is categorised into abiotic of non-living and
biotic of living components. Both the components of ecosystem and environment
are same.
1. Abiotic Components
the inorganic and non-living parts of the world.
consists of soil, water, air, and light energy etc.
involves a ,large number of chemicals like oxygen, nitrogen-, etc. and physical processes
including volcanoes, earthquakes, floods, forest fires, climates, and weather conditions.
Abiotic factors are the most important determinants of where and how well an
organism exists in its environment. Although these factors
interact with each other, one single factor can-limit the range of an organism.
a) Energy
Energy from the sun is essential for maintenance of life. Energy determines the distribution of organisms in
the environment.
b) Rainfall
c) Temperature
Temperature is a critical factor of the environment which greatly influences survival of
organisms. Organisms can tolerate only a certain range of temperature and humidity.
d) Atmosphere
It is made up of 21% oxygen, 78% nitrogen , 0.038% carbon dioxide and other inert gases
(0.93% Argon, Neon etc).
e) Substratum
Land is covered by soil and a wide variety of microbes, protozoa, fungi and small
animals (invertebrates) thrive in it
f) Materials:
(i) Organic compound
Such as proteins, carbohydrates, lipids, humic substances are formed from inorganic
compound on decomposition.
