2. Some Definitions
• Ecosystem: Defined area in which
a
community
lives
with
interactions taking place among
the organisms between the
community and its non-living
physical environment.
• An ecosystem is formed by the
interactions between all living and
non-living things
• Ecosystem is the basic functional
unit of ecology in which include
both living and non-living things
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3. This term was introduced by Ernst
Haeckl in 1869.
The word ecosystem was coined by
Tansley, A.G. (1935).
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4. What is an ecosystem?
Eco= Environment
System = Regularly interacting and interdependent
components forming a unified whole
Ecosystem = an ecological system;
= a community and its physical environment
treated together as a functional system
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5. Components of an Ecosystem
ABIOTIC
COMPONENTS
Sunlight
Temperature
Precipitation
Water or moisture
Soil or water chemistry
etc.
BIOTIC
COMPONENTS
Primary producers
Herbivores
Carnivores
Omnivores
Detritivores
etc.
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7. TYPES OF AN ECOSYSTEM
• Natural
– Terrestrial ecosystem
– Aquatic ecosystem
• Lentic, the ecosystem of a lake, pond or swamp.
• Lotic, the ecosystem of a river, stream or spring.
• Artificial, ecosystems created by humans.
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8. Terrestrial ecosystem
A terrestrial ecosystem is an ecosystem found only on a landform.
Four primary terrestrial ecosystems exist: tundra, taiga, temperate
deciduous forest, and grassland.
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9. Aquatic Ecosystem
• The two main types of aquatic ecosystems
are marine ecosystems and freshwater
ecosystems.
• Marine ecosystems cover approximately 71%
of the Earth's surface and contain
approximately 97% of the planet's water.
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11. • Freshwater ecosystems cover 0.80% of the
Earth's surface and inhabit 0.009% of its total
water. They generate nearly 3% of its net
primary production.
• Lentic: slow-moving water,
including pools, ponds, and lakes.
• Lotic: rapidly-moving water, for
example streams and rivers.
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15. Trophic level: All the organisms that are
the same number of food-chain steps from
the primary source of energy
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16. • The trophic level interaction involves three
concepts namely
• Food Chain
• Food Web
• Ecological Pyramids
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17. Food Chains
• The producers, consumers, and decomposers
of each ecosystem make up a food chain.
• There are many food chains in an ecosystem.
• Food chains show where energy is transferred
and not who eats whom.
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19. Example of a Food Chain
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20. Food Webs
• All the food chains in an area make up the food web of the area.
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21. Food web of a hot spring
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22. Food web of the harp seal.
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23. Trophic Levels Found on an Energy
Pyramid
• The greatest amount of energy is found at the base of the
pyramid.
• The least amount of energy is found at top of the pyramid.
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24. Summary
• Ecosystems are made up of abiotic (non-living,
environmental) and biotic components, and these
basic components are important to nearly all types
of ecosystems.
• Energy is continually input into an ecosystem in
the form of light energy, and some energy is lost
with each transfer to a higher trophic level.
• Energy is moved through an ecosystem via a food
web, which is made up of interlocking food
chains.
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25. References
• Odum, E.P.(1971), Fundamental of Ecology, Principles
and concept pertaining to the ecosystem. pp 8-33.
• Odum, E.P.(1983), Basic ecology, The ecosystem, pp 1382.
• Shrivastava, C.B.L. (1999), A Text Book of Fisheries
Science and Inland Fisheries, Ecology of Aquatic
Ecosystem, pp 160-206.
• Jhingran, V.G. (1991), Fish and Fisheries of India, Fish
culture in fresh water pond, Ecology, pp 273-328
• http://www.scribd.com/doc/14179924/13-Structureand-Function-of-Ecosystem
• http://www.globalchange.umich.edu/globalchange1/c
urrent/lectures/kling/ecosystem/ecosystem.html
• www.wikipedia.org/wiki/Ecosystem
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