Ecology

1. Ecology
Part B
Lecture 2Lecture 2
Human EcologyHuman Ecology

2. Human EcologyHuman Ecology
Nature of Human Ecology
Human-nature relationship
Contemporary human ecology
Anthropogenic Impact on the Environment

3. Why Study Ecology ?
 About organisms and their environment
 Fundamentals of all forms of life
 Architecture – Ecology - Interdisciplinary approach
 Physical science – biological science - life science…

4. Human EcologyHuman Ecology
Nature of Human Ecology
 Human are one of the most important entities in
ecosystems
 contributors
 participants
 receivers
 Powerful in affecting alteration in ecosystems and
ecological processes
 Unparallel capacity to modify their environment
 Capacity for recognition, reflection, and prediction
Humans have responsibility for true
stewardship and guardianship

5. Human-Nature Relationship
 The Imperialist Tradition – human apart from nature,
human domination and competitive interactions
.…Old Testament….English philosopher Francis Bacon (1561-
1626)….Charles Darwin (1809-1882)….
 The Arcadian Tradition – human as part of nature,
harmony of humans and nature
….Greek….Henry David Thoreau (1817-1862)….nature as an
extension of self…
 The Scientific Tradition – human integral part of the
system, systematic investigations of the total relations
….Ernst Haeckle (1870)

6. Contemporary Human Ecology
To gain knowledge toward the betterment of human-
environment condition
Issues covered
 Legal
 Economic
 Political
 Social
 Philosophical
……..

7. Growth of human population through human history
Duration Time Billions of people
From Old Stone Age to
1800 B.C.
2 – 5 million
years
From 0 to 1 billion
From 1800 B.C. to 2000
A.D.
200 years From 1 billion to 6 billions

8. Impact on the Atmosphere
Particulate Pollution
 Large or primary particulates range in size from 1 to 100
micrometer are directly injected into the atmosphere from
industrial smokestacks, gravel crushes, blast furnaces,
 Secondary acidic particles like sulfates or nitrates…cause acid
rain….
 Small particulates tend to be washed away by precipitation
Annual emission of particulates matter – 296 million tons,
123 million tons by USA only

11. Impact on the Atmosphere
Atmospheric Ozone /tri-molecular oxygen
Stratospheric ozone
has positive influence on human health, serving as a shield in
screening out damaging portion of ultraviolet radiation…
chlorofluorocarbons (CFCs) destroy the stratospheric ozone…
used as refrigerant, in seat cushions, metal cleaning and drying,
industrial sterilization of medical equipment, fast freezing of food
etc….
increase in ultraviolet radiation causes skin cancer, reduce
productivity of agricultural crops, destroy marine larva,
warming of earth’s atmosphere

12. Effect on the Atmosphere
Greenhouse Effect

Carbon dioxide plays critical role in controlling the Earth’s
climate

As an aerosol it absorbs and reflects or scatters incoming
radiation on the one hand and absorbs and radiates outgoing
infrared radiation on the other hand….latter one results in
greenhouse effect…

from burning of fossil fuel, destruction of forest
Consequences – global warming, rise in sea level, change in
climate,
precipitation….tsunami….typhoon….draught….flood….