This document provides an introduction to environmental science. It defines key terms like environment, lithosphere, biosphere, atmosphere, and hydrosphere. It describes the internal structure of the earth and gives details on the lithosphere, hydrosphere, biosphere, and atmosphere. It discusses the multidisciplinary nature of environmental studies and the importance of environmental study, including the need to conserve resources and protect biodiversity. The document outlines the scope of environmental science in areas like understanding ecosystems, pollution, and natural disasters. It stresses the need for public awareness in environmental protection through education and media.

1. ENVIRONMENTAL SCIENCE
INTRODUCTION
Dr Archana Chaudhary
Sr. Assistant Professor
Dept. of Environmental Science

2. WHAT IS ENVIRONMENT ?
• Environment derived from the French word
Environner, meaning Encircle or Surround
• Environment include:
• Biological entities
• Non-Biological entities
• The sum total of water, air and land, their
inter-relationships among themselves and with
the human beings, other living beings and
property.

3. LIFE : EARTH
lithosphere Biosphere
Atmosphere Hydrosphere

4. Lithosphere
• The earth’s crust consisting of the soil and rocks is the lithosphere.
• The main mineral constituents are compounds or mixtures derived from the
elements of Si, Ca, K, Al, Fe, Mn, Ti, O etc. (Oxides, Silicates, and
Carbonates).
• The organic constituents are mainly polysaccharides, organo compounds of
N, P and S. The organic constituents even though form only around 4% – 6%
of the lithosphere, they are responsible for the fertility of the soil and hence
its productivity.
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5. Internal structure of earth
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6. HYDROSPHERE
•Water resources both surface and ground
water.
•Only less than 1% of water resources are
available for human exploitation.
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7. Hydrological Cycle
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8. BIOSPHERE
• The biosphere is a capsule
encircling the earth’s surface
wherein all the living things exist.
• This portion extends from 10000 m
below sea level to 6000 m above
sea level. Life forms do not exist
outside this zone.
• The biosphere covers parts of other
segments of the environment viz.
Lithosphere, Hydrosphere and
Atmosphere.
• Simply we defined it “where life
present”
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9. ATMOSPHERE
• Atmosphere is a layer of gases that may surround a material body of
sufficient mass.
• The atmospheric composition on Earth is largely governed by the by-
products of the very life that it sustains.
• The Earth's atmosphere consists, from the ground up, of
the troposphere (which includes the planetary boundary layer or
peplosphere as lowest layer), stratosphere (which includes the ozone
layer), mesosphere, thermosphere (which contains
the ionosphere), exosphere and also the magnetosphere.
• Each of the layers has a different lapse rate, defining the rate of change in
temperature with height.
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10. Structure of Atmosphere
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11. DEFINATION OF ENVIRONMENT
• The Environment (protection) Act, 1986
defined Environment as the sum total of
water, air and land, there inter relationships
among themselves and with the human
beings, other living beings and property.
• Environmentalists defined Environment as the
mother of natural resources-energy, land,
water, atmosphere and minerals.

12. Multidisciplinary Nature of
Environmental Studies
• Biological Elements
• Physical Elements
• Cultural Elements

13. Biology

14. Chemistry

15. Physics

16. Earth Science

17. Social Sciences

19. Importance of Environmental study
• Environment issues being of International
importance.
• Environment issues being of National
importance.
• Problems cropped in the wake of
development.
• Explosively increase in pollution .
• Need for an alternative solution .

20. Importance of Environmental study
• Need to save humanity from extinction .
• Need for wise planning of Development .

21. Productive value of nature
• Advances in fields like Biotechnology.
• New medicines developed.
• Flowering plants and insects: Protect them
• Once a species is lost, man cannot bring it
back.
• For crops to be successful, the flowers of fruit
trees and vegetables must be pollinated by
insects, bats and birds.

22. Aesthetic/Recreational value of nature
• This is created by developing national parks
and wildlife sanctuaries in relatively
undisturbed areas.
• In an urban setting, green spaces and gardens
are vital to the psychological and physical
health of city dwellers.

23. The option value of nature
• Utilizing goods and services furnished by
nature vs. adverse impact on nature’s
integrity.
• We can use its resources sustainable and
reduce our impact on the environment.
• Or destroy its integrity.

24. SCOPE
• Study nature and history: a forest, a river, a mountain, a desert or a
combination of these elements.
• Our dependence on nature: Protect earth’s environmental
resources.
• Respect for nature and all living creatures .
• Awareness to know about various natural resources, their
conservation and management.
• Knowledge about ecological systems and their relationships.
• Information about biodiversity richness and the potential dangers
to the species of plants, animals and microorganisms in the
environment.
• Understand the natural and man induced disasters , pollutions (air,
water and land)

25. • The study exposes the problems of over population,
health, hygiene etc. and the role of arts, science and
technology in eliminating/minimizing the evils from
the society.
• To make judgments and decisions for the protection
and improvement of the earth.
• It enables one to evaluate alternative responses and
develop appropriate and indigenous eco-friendly skills
and technologies to various environmental issues.
• It enables to teach the need for sustainablity
• The study enables theoretical knowledge into practice
and the multiple uses of environment.

26. Research and Development: include research and development of pollution
control technology, clean fuel development, sustainable agricultural
practice, carbon credit
Green advocacy: Increase emphasis on implementation of various acts and
laws resulted in environmental lawyers, who could enforced pollution,
wildlife, forest protection related laws.
Green marketing : more emphasis on consumer good which are more eco-
friendly, Food products without contamination of pesticides, insecticides.
Increase use of products with ECO marks.
Green media: Mass media which include print media and electronic media
are Important means of spreading awareness about environment pollution
and conservation.

27. NEED FOR PUBLIC AWARENESS
• Everything is possible through public
awareness.
• Methods to propagate public awareness –
– Among students through education.
– Among people through mass-media.
– Among planners, decision makers, politicians and
administrators.

28. 17th Century has been described as the
AGE OF FAITH

29. 18th Century is considered as the
AGE OF REASONING

30. 19th Century was
AGE OF PROGRESS

31. 20th Century was AGE OF STRESS

32. Will 21st Century be
Age of Panic or Age of Peace?
You have to decide.

33. The “ecological footprint”
• The environmental
impact of a person or
population
• Overshoot: humans have
surpassed the Earth’s
capacity to support us
We are using 30% more of the planet’s resources
than is available on a sustainable basis!

34. Ecological footprints are not all equal