Ecology PPT OL
NAME______________________
Living things do not live in vacuums, their daily lives are based on _interactions_ with both _living_
and _nonliving_ things.
What is an ecosystem?
Groups of __________________________________ and their physical environment
There are two main components of an ecosystem:
__ Biotic (living) _
Descriptions:
populations of
organisms.
temperature,
& _ _______________________________ (nonliving) __
inorganic nutrients,
physical features,
and wind.
water,
Biotic Components: A Closer Look
Autotrophs are producers that produce food for ___________________________ and for consumers.
How do autotrophs make food?
______________________________ and chemosynthesis
Heterotrophs are consumers that take in premade food.
Biotic components
Consumers Vocabulary:
Herbivores – animals that eat plants
Carnivores – animals that eat other _____________________________________
Omnivores – animals that eat plants and animals
Decomposers - bacteria and fungi, that break down dead organic waste.
Detritus - partially ___________________________________________ organic matter in the soil and water;
beetles, earthworms, and termites are detritus feeders.
Consumers
Consumer Levels
Primary consumer – an organism that gets its energy from plants (producers)
Secondary consumer – an organism that gets its energy from primary consumers
____________________________________________ consumer – carnivores that eat other carnivores; a top-level
consumer, usually the top predator in the food chain
Energy Flow
What is energy flow?
• The movement of energy through the organisms in an ecosystem
What ______________________________ does energy flow through an ecosystem?
• Sun  Producers  Various levels of consumers
Energy Flow
• As energy flows from _autotrophs_ (producers) to _heterotrophs_ (consumers) much of the
energy is lost before the consumer can use it.
• In what forms is energy lost?
Heat
• Initial energy from an ecosystem comes from a consistent supply of ____________________ energy
**Remember energy in an ecosystem may be transferred or converted but will not be created nor
destroyed**
Energy balances
Nature of an ecosystem
Food chains vs. food webs
What is a food chain?
A diagram that links organisms together by who eats whom
•
Starts with _plant life_ and ends with an _animal_.
• Most food chains have no more than _4 or 5_ links
• Arrows show the direction __________________________________ is flowing_
• EXAMPLE: grass zebra lion
Food chain
FOOD WEB
Most consumers feed on and are eaten by _more than one_ other _______________________________
What is a food web?
•
A combination of several food chains showing all of the possible energy pathways
• What is a trophic level?
All of the organisms that feed at a particular link of the food chain/web
Grazing food web –
The upper portion of a food web based on a living plant as the _________________________________
Detrital food web –
The lower portion of a food web based on detritus
Forest food webs
Ecological Pyramids
Why are food chains so short?
Only about 10% of energy is useable from one trophic level to the next
• The number organisms drastically _______________________________ as you go up in level of a food
chain
What is an ecological pyramid?
A series of blocks representing the biomass of particular organisms on a particular trophic level
What is biomass?
The amount of living material in the population of an organism
Ecological pyramid
Biochemical cycles
What are biochemical cycles?
• The path by which important nutrients/molecules travel through an ecosystem.
3 Important Cycles:
• Water Cycle
• __________________________ Cycle
• Nitrogen Cycle
The Water Cycle
Water movement:
Land  Atmosphere:
• Liquid  Gas
• ______________________________________ from rivers, lakes and oceans
• Transpiration from plants
Atmosphere  Land
• Gas  Liquid
• Precipitation over land and bodies of water
• Runoff forms bodies of water (lakes, rivers, oceans)
• Ground water seepage into aquifers
The water cycle
The Carbon Cycle
Carbon Movement:
Land/Water  Atmosphere
• Respiration
• Combustion
Atmosphere Land/Water
• _______________________________________
• Dissolved CO2
** Carbon is stored as _fossil fuels__ from decaying organisms.**
The carbon cycle
The Nitrogen Cycle
Nitrogen Movement:
• Nitrogen Fixation  _______________________________________________ found in legume roots
converts N2 gas into _Ammonia (NH4)_
•
_Decomposers_ break down waste and organic remains into _Ammonia (NH 4)_
• Nitrification  bacteria convert ammonia into _Nitrite (NO2)_ and _Nitrate (NO3)_ to be used
by _plants_
• Denitrification  Bacteria converts _ammonia_ back into _Nitrogen gas (N2)
The nitrogen cycle