This document provides definitions and concepts related to environmental studies. It discusses: 1) Basic definitions of key terms like environment, ecology, ecosystem, and environmental science. 2) The objectives and guiding principles of environmental studies according to UNESCO, including creating awareness, imparting knowledge, developing concern for the environment, and attaining harmony with nature. 3) The main components of the environment - atmosphere, hydrosphere, lithosphere, and biosphere. It also describes the layers of the atmosphere. 4) The relationship between humans and the environment, and how increased human impacts like pollution, deforestation, and industrialization are placing stress on the environment's ability to sustain life.

1. Subject:-Environmental Studies(2110007)
Topic:-Introduction to Environment,Ecology and
Ecosystem

3. Content
1.1 Basic definitions
1.2 Objectives and guiding principles of environmental studies
1.3 Components of environment
1.4 Structures of atmosphere
1.5 Man-Environment relationship
1.6 Impact of technology on the environment

4. Basic Definitions
1. Environment
 Derived from the French word
“Environner” means to circle or
surround
Definition
‘External surroundings and
conditions which directly or
indirectly affects the living
organism’
or
‘it is the sum total of water, air and
land, interrelationship among
themselves and also human
beings, other living organisms and
property’

5. Parts of Environment (Division)
• Biotic
 Made up of all living organisms
(Plant, animals and microorganisms)
including their reactions, interactions
and interrelated actions.
• Abiotic
 Composed of all external physical
factors like, temperature, humidity,
water, soil, mineral, gases etc.
 Provides both habitation and raw
material for the synthesis of organic
food.
The Biotic and Abiotic components are in a dynamic state, that is they are constantly affect
each other and cannot be isolated from each other
Any constituents of the environment which is directly or indirectly affect the growth and
development of an organism is called environmental or ecological factor
Eg. Climate factor, topographic factor, fire etc.

6. Basic Definitions
2. Ecology
 Ecology = oikos + Logos (Oikologie, Greek word)
• oikos- house, habitation or place for living
• “logos” means Studies
 Definition
• Ecology is the study of the interrelationship between living organisms
and their physical and biological environment”

7. Basic Definitions
3. Ecosystem
 Ecosystem = Eco + System
• Eco means environment
• System means an interacting and independent complex
 Definition
Organisms of any community interacts themselves and functional
relationship with the environment. The structural and functional system
of communities and environment is called as ecological system or
ecosystem.
It is a community of interdependent organisms together with the
environment
Any unit that includes all the organism in a given area interacting with
the physical environment, so that a flow of energy leads to clearly
defined trophic structure, biotic diversity and material cycles withinthe
system.

8. Basic Definitions

9. Basic Definitions
3. Environmental Science
 Definition
 Is the scientific study of
environment and our place in
it.
 It is the study of earth, air
water, living organisms and the
man with his impact on
environment.
 Multidisciplinary
 Physics
 Chemistry
 Biology
 Geology
 Sociology
 Ecology
 Forestry
 Engineering etc.

10. Basic Definitions
Scope of Environmental Science
Few basic aspects are
Natural resource- their conservation and management
Ecology and biodiversity
Environmental pollution and control
Social issues in relation to development and environment
Human population and environment

11. Objectives and guiding principles of
environmental studies
• According to UNESCO (1971)
 Objectives
Creating awareness about environmental problems
Imparting basic knowledge about environment and its allied
problems
Developing an attitude of concern for environment
Motivating public to participate in environment protection
and environment improvement
Acquiring skills to help the concerned individuals in
identifying and solving environmental problems
Striving to attain harmony with nature

12. Objectives and guiding principles of
environmental studies
• According to UNESCO (1971) (United Nations Educational,
Scientific and Cultural Organization)
 Guiding principles of environmental education
 The environment should be comprehended as a system which is a functional
unit composed of organized, interacting and independent parts
 Environmental education should be compulsory, right from the primary up
to the post-graduate
 Environmental education should have an inter-disciplinary approach
 Environmental education should take in to account of historical
perspectives, the current and the potential future issues.
 Env. Edu should emphasize the sustainable development
 Env. Edu should reflect the necessity of environmental impact analysis in
proposed developmental project
 Env. Edu should emphasize the necessity of seeking international co-
operation in environmental planning.
 Env. Edu should lay more stress in to practical activities and first hand
experiences

13. 1.3 Components of Environment

14. Atmosphere
o Atmosphere:
o Mixture of various gases, water vapors and subatomic particles
that entirely cover the earth extending several thousand
kilometers.
o Major gases
o Nitrogen (78%), Oxygen (21%), Argon (0.9-1.0%), and carbon
dioxide(0.032%)
o Minor Gases
o Neon, Helium, Methane, Hydrogen, Carbon monoxide, ozone etc.
o An important life facilitating layer
o Absorbing major portion of electromagnetic radiations and cosmic
rays
o Absorbs infrared radiations, thus maintain temperature of earth.
o Provides oxygen and sunlight.
o Weather:
o It is the short term variations (like hourly, daily or weekly) at a given
place
o Climate
o If the weather remains constant for long duration (like seasonal
variation) of time is called climate

15. Hydrosphere
o Hydrosphere:
o All type of water resources, namely-ocean, sea,
rivers, lakes, ponds, reservoirs, polar ice cap,
glaciers, ground water and water vapor are
collectively known as hydrosphere.
o About 70% of earth surface is covered with
water (1.4 billion km3)
o The northern hemisphere is dominated by
land surface while southern hemisphere is
dominated by sea
Water distribution Percentage
Ocean and Sea 97%
Ice at polar regions 2.3%
Ground water 0.67%
Lake, pond, river, stream 0.03%

16. Lithosphere
o Lithosphere
o The upper layer of the earth’s crust is called
lithosphere. It is made up of soil, minerals,
rocks and organic as well as inorganic
matter (64 to 96Km).
o Have a major role in producing food for
human and animal and also in decomposing
wastes.
o Soil
o Mixture of air, water, mineral and organic matter
o Obtained from weathering of rocks
o Organic matter in the soil is decomposed by micro-
organism thus forming biomass
o Rocks
o Igneous-eg. granite
o Sedimentary- eg sandstone
o Metamorphic- eg. Marble

17. Biosphere
o Biosphere
o It is the portion of earth surface,
hydrosphere and atmosphere where
life exist.
o Extends from lowest sea bed level
to about 24 km of atmosphere
o Living organism interact with one
another in biosphere and sustain
their life
o Use basic resources form biosphere
(air, water, food, and sunlight)
o The waste products in the form of
gaseous, solid and liquid are
discharge in to biosphere
o System is operating for millions of
years but show stress now due to
impact of human

18. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Troposphere
• Stratosphere
• Mesosphere
• Thermosphere/Ionosphere
• Magnetosphere/Exosphere

19. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Troposphere
– Lowest portion of the atmosphere
– Thickness
• 8 Km (pole)
• 16 km(equator)
• Average 10-11 km
– Temperature
• Air near the ground is heated by
radiation from earth
• But decreases with altitude
• decrease at a rate of 5-70C/Km
(lapse rate)
– Contains 70% of atmosphere’s
mass
– Density decreases with altitude
– The cold layer (-560C), shows
positive lapse rate known as
tropopause

20. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Stratosphere
– Stable layer above stratosphere
– Thickness
• 50 to 55 km above the surface
– Temperature
• Up to 20 km remains constant
• Then increases with increase in
height
– Known for the presence of
Ozone (around 20 Km from
ground)
• Protect from harmful ultraviolet
radiations
– Layer separating stratosphere
from mesosphere called
stratopause

21. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Mesosphere
– Thickness
• Above stratosphere and extends
up to 80 km
– Temperature
• Decreases with altitude
– Importance
• Sound waves and short radio
waves coming from earth are
reflected back from this layer.

22. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Thermosphere
– Thickness
• Extends up to 500 km
– Temperature
• Increases with altitude
– Also known as ionosphere
• Ionization of elements like oxygen
and nitric oxide take place in the
uppermost portion

23. 1.4 Structures of atmosphere
Troposphere
Stratosphere
Mesosphere
Thermosphere/Ionosphere
Magnetosphere/Exosphere
Stratopause
Tropopause
Mesopause
Kilometer
11
20
50
55
80
500
2000
-100 -40 -20 0 20 40-80 -60
Degree
• Exosphere
– Thickness
• Extends up to 2000 km
– Temperature
• Increases with altitude
• Very high temperate (>12000C)
– Almost airless and empty
– Probably contains Hydrogen gas
in ionized stage

24. 1.4 Structures of atmosphere

25. • Waste generated by plants and animals
– Assimilated for centuries
– Assimilative capacity is tremendous but not infinite
• Self purification system of environment
– For every natural act of pollution, there are natural forces
that restores the quality of environment
• Dispersing smoke from forest and volcanos
• Washing out of waste generated by plants and animals by rivers
• Conversion of waste in to soil by microbial activity
• Increased quantity of pollution
– Showing sign of stress in environment
1.5 Man-Environment relationship

26. • Man is the only living
organism capable to modify
the surrounding to its need
– Hunting animals and cut trees
for basic need
– Started cultivation and for
that started cutting trees and
forest
– To increase comfort started
disturbing each and every
component
– Largescale deforestation
• Increased carbon dioxide
• Disturbed food chain
?

27. • Industrial revolution
– Use of fossil fuel
• for power
• For vehicle
• For industry
– Increased pollution
– More quantity of carbon
dioxide
– Discharge of waste to rivers
– Rivers get polluted
– Global warming
– Acid rain
– Ozone depletion
– Human explosion

28. Quantified list of impact
• Emission of CO2
– Rise of temperature several degrees by 2050
– Effect food production and flooding of coastal regions
• Chlorofluorocarbon and halons
– Faster depleting ozone
– More ultraviolet radiation to surface
• Increased skin cancer
• Eye cataracts
• Weaker immune system
– Acid rain
– food crops affected
• Deforestation decertification and destruction of wetland
– 36,500 species plants and animal extinct each year
– If continued same rate, 50,000 to one million in next 20 year
– About 8.1 Mkm2 productive land become dessert in the last 50 years
– Each year about 61000km2 new dessert are forming
– Top soil eroding faster than it forms
– Salt built up in the top soil reduced by 1/3
– Half of the worlds original expanse of tropical forest are cleared
– Reduction in biodiversity
– 25 to 50% worlds wetland have been drained, built upon or seriously polluted

29. • Ocean pollution
– Most waste dump in water and land end up in ocean
– Oil slicks
– Floating plastic debris
– Polluted estuaries and beaches and contaminated fish and shell fishes
• Drinking water
– In developing countries 61% of the people in rural area and 26% in urban area do
not have safe drinking water
– Each year 5 million people die from preventable water borne diseases
Quantified list of impact

30. • Application of technology results human well
beings but causing environmental disruptions
– Impacts
• Direct impact
– Accidents
– Pollutants
– Exhausting resources
– Change in landscape
– Removal of vegetation forest etc.
• Indirect impact
– Secondary impact of chain impact
» Eg. Extinction of animal sp. as a result of deforestation
• Cumulative impact
– Generally result of small change of environment.
1.6 Impact of technology on the environment