Introduction to ecology and env - Kathmandu University Introduction.pdf · Subodh Sharma...
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Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 1 1 hr. Unit 1.1 Introduction to ecology and environment PG diploma in Environment Education program Supported by NORAD
Transcript of Introduction to ecology and env - Kathmandu University Introduction.pdf · Subodh Sharma...
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 1
1 hr.Unit 1.1Introduction to ecology and environment
PG diploma in Environment Education program
Supported by NORAD
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 2
What is ecology?
Definition of Ecology- the scientific study of interactions between organisms and their environments, focusing on energy transfer
It is a science of relationships between living organisms and their environment
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 3
What is ecology?
The word “ecology” was first proposed by the German biologist Ernst Haeckel in 1869
It is derived from the Greek
Environmental sciences is an area of modern ecology
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 4
History of ecology?
Alexander von Humboldt, often considered the true father of ecology, reported impressive number of species in his book titled “Idea for a Plant Geography” published in 1805.
In 1850, Charles Darwin published “On the Origin of Species By Means of Natural Selection”.
By the 19th century, Lavoisier and de Saussure discovered nitrogen cycle.
Austrian Geologist Eduard Suess proposed the term “biosphere” in 1875.
In 1920, Vladimir I. Vernadsky described the principles of the biogeochemical cycles.
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 5
History of ecology?
It was in 1935 that Arthur Tansley coined the term ecosystem.Human ecology began in the 1920s.Ecology became a central part of the World’s politics as early as
1971.In 1972, the UN held the first international conference in the
human environment in Stockholm.In 1992, Earth Summit was held in Rio de Janeiro.In 1997, the dangers biosphere is facing was realized from an
international conference leading to the Kyoto Protocol.
In Kyoto, most of the world’s nations recognized the importance of looking at ecology from a global point of view. On a worldwide scale, and to take into account the impact of humans on the Earth’s environment
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 6
The environment is made up of two factors:
Biotic factors- all living organisms inhabiting the Earth
Abiotic factors- nonliving parts of the environment (i.e. temperature, soil, light, moisture, air currents)
What do you mean by environment?
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 7
Scope and relevance of ecology…
Ecology is a basic division of biology
It is an integral part of any and all of the taxonomic divisions
Source: Fig. 1.1 Odum, 1971
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 8
Levels of OrganizationBest way to delimit modern ecology is to consider it in terms of the concepts of level of organization (Odum, 1971)
Diagram Showing Ecological Organization From Odum (1971)
Genes Cells Organs OrganismsPopula-tions
Commun-ities
BIOTICCOMPONENTS
Plus
ABIOTICCOMPONENTS
Equals
BIOSYSTEMS Genetic Systems
CellSystems
OrganSystems
OrganismicSystems
PopulationSystems
Ecosystems
Matter Energy
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 9
Levels of Organization
Organism
Population
Community
Biosphere
Ecosystem
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 10
Levels of Organization
Organism- any unicellular or multicellular form exhibiting all of the characteristics of life, an individual.
•The lowest level of organization
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 11
Levels of Organization
Population-a group of organisms of one species living in the same place at the same time that interbreed and compete with each other for resources (ex. food, mates, shelter)
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 12
Levels of Organization
Community- several interacting populations that inhabit a common environment and are interdependent.
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 13
Levels of Organization
Ecosystem- populations in a community and the abiotic factors with which they interact (ex. marine, terrestrial)
Subodh Sharma Dr.nat.tech.; Aquatic Ecology Centre, P.O. Box: 6250, [email protected]. 14
Levels of Organization
Biosphere- life supporting portions of Earth composed of air, land, fresh water, and salt water.
•The highest level of organization
