Transcript Ecology - BiologyGerlach

Ecology
Chapters 34-36
Mrs. Gerlach
2010-2011
What is Ecology?

The study of interactions among
organisms with each other and with their
environment
Factors
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Biotic- All living organisms
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Abiotic- non-living components
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Examples: soil, rocks, sunlight, wind, rain, etc.
Levels of Organization
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Smallest to largest
Species- individuals that can breed with one
another
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Example: Ducks
Population- all the individuals of the same
species in an area
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Example: Ducks in Sioux Falls
Levels of Organization
Continued
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Community- All the different species in an area


Example: Ducks, maple trees, and dragonflies in
Sioux Falls
Ecosystem- the community plus the abiotic
factors of an area
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Example: Ducks, maple trees, dragonflies,
temperature, soil, and rainfall of Sioux Falls
Levels of Organization
Continued

Biome- Major biological communities that
occur over wide areas

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Tundra
Biosphere- all the ecosystems of the world
Biomes

Major types of ecosystems
Movement of Energy

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Producers - Organisms that produce their
own food (from what source?)
Consumers – eat producers
Secondary Consumers – eat organisms
that eat producers
Decomposers – feed on wastes
Energy Continued

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Autotroph (producers)- Makes their own
food
Heterotroph (consumers)- Cannot make
their own food
Energy Continued
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Herbivore – eats plants
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Carnivore – eats animals
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Omnivore – eats either
Energy Continued

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Trophic levelslevels in which
energy is
transferred from
one organism to
the next.
Only 10% of the
energy from
organism is
transferred to
the next trophic
level
Hawk
10
Snake
100
Rodent
1,000
Plants
10,000
Energy Continued

Trophic levels can also
been shown with food
webs and food chains
Food Web
Food Chain
Interactions within an ecosystem


Habitat- The place where a population
lives
Niche- the physical and biological
conditions in which an organism lives and
the way in which the organisms uses
those conditions.
Interactions Continued

Competition- compete for resources

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No two species can occupy the same niche\
Predation- one organism captures and
feeds on another organism (prey)
Symbiotic Relationships
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Mutualism- both species
benefit

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Commensalism- one
species benefits while the
other is neither harmed
or helped

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Example: insects
pollinating flowers
Example: Barnacles and
whales
Parasitism- one species
live in or on another and
harms the prey
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Example: Tick
Populations
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Population Density- how many species live in one area at
one time.
Exponential Growth- Rate at which a population can
grow

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Limiting factors- factors that can limit a population

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“S” curve- rapid growth with a steady or decrease in the
population
Examples: food, shelter, water, etc.
Carrying capacity- number of species in a population in
which the habitat can hold.

Will normally flatten out on a graph
Ecological Succession

- Predictable changes that occur in a community
over time
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Primary Succession- occurs on land where no
soil exists

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Example- after a volcanic eruption
Pioneer Species- the first species to populate an
area
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Normally a plant/algae
Successions Continued
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Secondary
Succession- occurs in
areas where there has
been previous growth

Ex: fires, abandoned
fields
Chemical Cycles
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Nitrogen Cycle

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80% of the air is
made up of nitrogen
Nitrogen is a fertilizer
for plants
Nitrogen Fixationbacteria taking
nitrogen from the air
and converting it to a
form used by plants
Cycles Continued
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Water Cycle
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Transpiration- water
given off by plants
Evaporation- adding
moisture to the air
Precipitation- water
that leaves clouds
Excess water is either
absorbed into the soil
or run into the ocean
Cycles Continued
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Carbon Cycle
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Producers consume
Carbon Dioxide and
create food-release
oxygen
Animals breathe in
oxygen and release
carbon dioxide
Burning of fossil fuels
also adds carbon
dioxide to the air