Ecosystems

Ecosystems• What is an

ecosystem?• A collection of all

the organisms that live in a particular place, together with their nonliving and living environment.

Because ecosystems are made up of both living and nonliving things, an ecosystem is shaped by both biotic and abiotic factors.

• What are biotic factors?

• What are abiotic factors?

• The living influences on an organism.• plants• animals• fungi• bacteria

• The physical, or nonliving, factors that shape an ecosystem.• moisture• temperature• wind• sunlight • soil

Together, biotic and abiotic factors determine the survival and growth of an organism and

the productivity of the ecosystem in which the organism lives.

Sunlight

Plants

moisture

sand

Energy in an Ecosystem *Life in an ecosystem requires a source of energy.*

• What are producers?

• Where do producers get the energy to make their own food?

• Producers are the organisms in an ecosystem that make their own food.• Producers provide energy for

other organisms in an ecosystem.

• Either from the sun or from inorganic chemical compounds.

This image uses chlorophyll abundance to show the distribution of producers

• What are producers also known as?

• What are photoautotroph's?

• What are chemoautotroph’s?

• Autotrophs. “auto” = self; “troph” = feeder

• Autotrophs who use energy from the sun (through photosynthesis) to make their food

• Autotrophs who use energy from inorganic chemical compounds to make their food

• Chemosynthesis is the process by which organisms form carbs using chemicals, rather than use light, as an energy source.This is found in sulfur rich salt marsh flats and in hydrothermal pools in Yellowstone National Park.

carbon dioxide + water +hydrogen sulfide + oxygen

sugar + sulfuric acid

• What are consumers?

• What are consumers also known as?

• organisms that get their energy by eating other living or once-living resources.

• Heterotrophs. “Hetero” = other; “troph” = feeder

• There are different types of heterotrophs based on what they eat. What are they?

• Herbivores eat plants.• Carnivores eat animals.• Omnivores eat both

plants and animals.• Detritivores eat detritus

(dead organic matter) ex. millipede

• Decomposers are detritivores that break down organic matter into simpler compounds. This is important to an ecosystem b/c it returns vital nutrients back into the environment. Ex. fungidecomposer

carnivore

ominvore

detritivore

Feeding Relationships• What is a food

chain?• A series of steps in

which organisms transfer energy by eating and being eaten.

• A food chain follows the connection between one producer and a single chain of consumers within an ecosystem.

Energy flows through an ecosystem in one direction, from the sun or inorganic

compounds to autotrophs (producers) and then to various heterotrophs (consumers).

Feeding Relationships

energy transferredenergy

lost

• Each step in a food chain is called a trophic level.

• Trophic levels are the nourishment levels in a food chain.• Primary consumers are

herbivores that eat producers. • Secondary consumers are

carnivores that eat herbivores.• Tertiary consumers are

carnivores that eat secondary consumers.

• Omnivores, such as humans that eat both plants and animals, may be listed at different trophic levels in different food chains.

Energy Transfer• How much energy is

transferred from one trophic level to the next?

• Why so little?

• Only 10%.

• Organisms use much of the energy they consume for life processes, such as respiration, movement, and reproduction.

Energy TransferThe amount of

energy available at each trophic level can be

identified using an energy

pyramid

100%

10%

1%

.1%

•A food web shows a complex network of feeding relationships.

•It emphasizes complicated feeding relationships and energy flow in an ecosystem.

•An organism may have multiple feeding relationships in an ecosystem.

Producers

Primary consumers

Secondary consumers

Tertiary consumers