Ch 4 : Introduction to Ecology
Ecology is the study of INTERACTIONS
between organisms and the living
(biotic) and nonliving (abiotic)
components of their environments.
• Observations, data collection,
explanation of trends and patterns.
• Many/all areas of science
– Taxonomy, biochemistry, cell type, etc.
• Hunter – Gatherer societies
10,000 – 12,000 y.a.
• Agricultural societies
impact on Earth
• Today’s exploding
population
> 6 billion
Ecology Related Issues
Think “ecosystem services” …. What service does
each area do ? What job does it have ? Is it able to
efficiently do that job? What is the overall impact?
1. Use of water, energy, food, space and other
resources.
2. Disposal of waste is also a big issue
3. Mass extinctions – species are currently
disappearing faster than dinosaurs
4. Thinning Ozone layer – related to CFC’s and
pollution. Increases UV radiation
5. Green house gasses are increasing – creating global
warming.
Ecosystem Services
• Resources that are produced by natural and
artificial ecosystems…. Food we eat, oxygen we
breathe, water we drink…….
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Purification of water and air
Preservation of soil and renewal of soil fertility
Prevention of drought and flood
Regulation of climate
Maintenance of biodiversity (food, cover, pollination)
Movement and cycling of nutrients (H2O, C, N, etc)
Detoxification and decomposition of wastes
Aesthetic beauty !
• Biosphere : layer of Earth that supports life
roughly 13 miles thick ( 7 miles into
atmosphere and 7 miles down into the
oceans !!!)
• Ecosystems: All of the living organisms and
the nonliving environment in a particular
place
– Biotic (all the living and once-living things)
– Abiotic (physical features)
• Biomes : large regions of the globe defined
by similar climate and vegetation
• Communities: All the living organisms
that interact in a given area
• Population: All the members of a given
species in a defined area
• Species: Organisms that are genetically
similar enough to breed in nature and
produce viable offspring.
– Measure of biodiversity = variety of living
organisms in a given area
– D, K, P, C, O, F, G, Species (Scientific name)
• Biotic factors:
– living and once-living
components in the
environment
- plants, animals, bacteria
fungi and protista
• Abiotic factors :
– nonliving components
in the environment; things
Like wind, temperature
precipitation, sunlight
Succession
• Change in an area’s physical features over time
– new species are now better suited or less
suited. Species themselves also change
physical features. (needles from pine trees make
the soil under the tree more acidic – different
plants like acidic soil)
• Primary succession – start from scratch
• Secondary succession – change leads to more
change leads to more change
• Equilibrium
Pioneer species  changes  climax community
Energy Flow
• Trophic levels….food chains and food webs
– 10 % rule (Energy pyramid)
• What else is the material and energy used for?
• GO TO SOCRATIVE APP and answer ….. 701439
– Producers
• Plants
• Protista like algae
– Consumers
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Herbivores
Omnivores
Carnivores
Scavengers
Decomposers
Detritivores : eat detritus or ‘waste’ – crayfish chewing on dead fish
is different than bacteria or fungi chemically digesting dead fish.
Practice Web: Meadow
• Construct the following food chains, they
will overlap to create a Meadow Food Web
• Identify (color code) all the herbivores,
carnivores, omnivores and detritivores in
the food web when you are finished
1. Red
fox feed on raccoons, crayfishes,
grasshoppers, red clover, meadow voles and gray
squirrels
2. Red clover is eaten by grasshoppers,
muskrats, red foxes and meadow voles
3. Meadow voles, gray squirrels and raccoons all
eat parts of white oak trees
4. Crayfishes feed on algae and detritus and they
are eaten by muskrats and red foxes
5. Raccoons feed on muskrats, meadow voles,
gray squirrels and white oak trees.