Ecology

Study of interactions between organisms and their environments.

Biotic Factors

Biosphere – life-supporting layer of Earth

Biotic factors – all living organisms in a

biosphere

Abiotic Factors

Nonliving factors in an environment

Examples:

Air currents

Temperature

Moisture

Light

Soil

Organization of Life

Organisms

Populations

Communities

Ecosystems

Biosphere

Feeding Relationships

Autotrophs

Heterotrophs

Carnivores

Omnivores

Herbivores

Decomposers

Trophic Relationships

Autotrophs

1st level consumers (herbivores)

2nd level consumers(omnivores or carnivores)

3rd level consumers(omnivores or carnivores)

4th level consumers (top predators)

RULE OF 10

Only 10% of energy is transferred from one

trophic level to the next.

Example:

It takes 100 kgs of plant materials (producers)

to support 10 kgs of herbivores

It takes 10 kgs of herbivores to support 1 kg

of 1st level predator

Energy Pyramid

1st level consumer

or primary

consumer

2nd level consumer

or secondary

3rd level consumer

or tertiary

4th level consumer

or quaternary

Biomass Pyramid

Symbiosis – “living together”

Relationship

Type

Species A

Species B

Commensalism + 0

Mutualism + +

Parasitism + -

Symbiosis – “living together”

Relationship

Type

Species A

Species B

Competition - -

Predation + -

Nutrient Cycles

Water cycle

Carbon cycle

Nitrogen cycle

Water cycle

Evaporation

Condensation

Transpiration

Precipitation

Runoff

Groundwater

Carbon cycle

Combustion

Photosynthesis

Cellular Respiration

Decomposition

Fossil fuels

- burning

- Burning calories; metabolism

Nitrogen cycle

Atmospheric nitrogen

Runoff

Fertilizers

Decomposition

Nitrogen fixation

Synthesis of amino acids

Nitrogen cycle

Biological Magnification

Biological Magnification

Also called biomagnification or

bioaccumulation

The process of toxic substances building up

in the tissues of organisms over time.