The scientific study of interactions among organisms and their environments.

BIOSPHERE BIGGESTBIOMEECOSYSTEMSCOMMUNITIESPOPULATIONSORGANISM SMALLEST

• THE LAYER OF PLANET EARTH THAT SUPPORTS LIFE• IT INCLUDES LANDMASSES, BODIES OF FRESHWATER & SALTWATER, AND ALL LOCATIONS BELOW EARTH’S SURFACE THAT SUPPORT LIFE• CONTAINS LIVING & NON-LIVING FACTORS:• BIOTIC: LIVING FACTORS• PLANTS & ANIMALS

• ABIOTIC FACTORS: NON-LIVING FACTORS• TEMPERATURE, SOIL TYPE, RAINFALL, AIR CURRENTS, WATER CURRENTS, AVAILABLE NUTRIENTS

• LARGE GROUP OF ECOSYSTEMS THAT SHARE THE SAME CLIMATE• LAND BIOMES

• TUNDRA, BOREAL FOREST, TEMPERATE FOREST, TEMPERATE WOODLAND & SHRUBLAND, TEMPERATE GRASSLAND, DESERT, TROPICAL SAVANA, TROPICAL SEASONAL FOREST, TROPICAL RAIN FOREST

• INTERACTION BETWEEN A BIOLOGICAL COMMUNITY AND ALL OF THE ABIOTIC FACTORS THAT AFFECT IT• AN ECOSYSTEM CAN BE LARGE OR SMALL• THE BOUNDARIES OF AN ECOSYSTEM ARE SOMEWHAT FLEXIBLE, CAN CHANGE, AND MIGHT OVERLAP OTHER ECOSYSTEMS

• GROUP OF INTERACTING POPULATIONS THAT OCCUPY THE SAME GEOGRAPHIC AREA AT THE SAME TIME• ORGANSIMS MAY OR MAY NOT COMPETE FOR THE SAME RESOURCES

• ORGANISMS THAT LIVE TOGETHER IN A COMMUNITY CONSTANTLY INTERACT• COMPETITION – FOR A RESOURCE (EXAMPLE: FOR WATER or A MATE)• PREDATION – ONE ORGANISM EATS ANOTHER ORGANISM FOR FOOD

•OTHER RELATIONSHIPS• MUTUALISM – RELATIONSHIP BETWEEN TWO ORGANISMS THAT BENEFITS BOTH ORGANISMS• COMMENSALISM – RELATIONSHIP BETWEEN TWO ORGANISMS THAT BENEFITS ONE AND THE OTHER IS NOT HELPED NOR HARMED• PARASITISM – RELATIONSHIP BETWEEN TWO ORGANISMS THAT BENEFITS THE ONE AT THE EXPENSE OF THE OTHER

• ORGANISMS OF A SINGLE SPECIES THAT SHARE THE SAME GEOGRAPHIC LOCATION AT THE SAME TIME• INDIVIDUAL ORGANISMS OFTEN COMPETE FOR THE SAME RESOURCES

• AN INDIVIDUAL ORGANISM

PRODUCERS (or AUTOTROPHS): Make their own food by using energy from the sun

example: plants

CONSUMERS (or HETEROTROPHS): Don’t make their own food. They eat other organisms.

examples: carnivores, herbivores, omnivores, scavengers, decomposers

CARNIVORES eat meat (other animals)

HERBIVORES eat plants

OMNIVORES eat meat & plants

SCAVENGERS feed on already dead organisms

DECOMPOSERS break down dead & decaying material into simpler molecules

Simple linear model to show how matter and energy move through an ecosystem.

Algae fish heron

The food chain shows how nutrients & energy move from autotrophs to heterotrophs and eventually to decomposers.

A food chain usually has 3 links, but never more than 5.

A portion of energy is lost as heat at each link.

Each step in the food chain is called a trophic level or feeding step.

Only 10% of energy is passed on from one trophic level to the next.

Food chains do not show the complex interactions between species.

A food web shows all the possible feeding relationships at each trophic level in a

community.

Grass Seeds Berries

Chipmunk Deer Marmot Grouse

Hawk Coyote

Grizzly Bear Mountain Lion3rd Order Consumers

2nd Order Consumers

1st Order Consumers

Producers

Trophic Levels

Shows the decreasing amounts of energy or number of organisms needed at each trophic level.