Ecosystems

What is an Ecosystem?Let’s take a look at the word:

• Eco- means “environment”• System means “a group of parts that work

together as a unit”.

An ecosystem is a system made up of the environment and all of the living things that live there. *All living things have to be able to meet their basic needs there.

What are the parts of an ecosystem?

Within each ecosystem, there are individuals, populations, and communities.

Individuals within ecosystems are one of that species. Populations within ecosystems are made up of all of that

species that lives in the same place at the same time.Communities within ecosystems are made up of all of

the populations of all the different species that live in the same place at the same time.

Let’s take a look at this….This is one otter. This is an example

of an individual.

This is a group of otters. This is an example of a

population.

These are some of the other populations that live in the same

river as the otters.Together they all make up the

community.

Another way to think about it… You are a person. You are one part of your

family. You are the same as an individual. All of the people in your family who live in

your house with you make up the population.

All of the people in your neighborhood- mailman, police officers, teachers, neighbors- make up the community.

Non-Living Parts of the Ecosystem

Every ecosystem has non-living parts. Some of these are:

• Sunlight• Water• Soil• Air

• TemperatureThe non-living parts of the ecosystems interact with the living parts af the ecosystems.

Homes for Living ThingsAn environment that meets the needs of

an organism is called a habitat.Depending on the organism, it may only

make use of a small part of its habitat while some organisms such as birds that fly, spread out over the habitat.

What are an organism’s basic needs?

All living things have 5 basic needs: Food Water

Air/Oxygen Shelter

Reproduce

The Main Source of EnergyThe sun is the main source of energy for ALL

living things. Animals do not get energy directly from the

sun, but they eat plants that do.

How Energy Moves Through Ecosystems

Scientists describe the way that energy moves through ecosystems as a food chain.There are 3 levels to every food chain:

Producers Consumers

Decomposers

Food Chains Producers make their own food. These are

plants and protists such as algae.(Producers get energy from the sun)

Consumers eat other living things for energy.(Consumers eat producers)

Decomposers feed on the waste of plants and animals or on their remains when they die.

Here is an example

Energy Pyramid All organisms need energy from food to live. An energy pyramid shows how much food

energy is passed from one organism to another along a food chain.

The base of the energy pyramid represents producers; these organisms use energy from the sun to make food through photosynthesis.

The second level of the energy pyramid represents herbivores, or plant eating animals. This level is made up of primary consumers.

The third level of the energy pyramid represents carnivores, or meat eating animals. These are secondary consumers because they are the second organism to consume something else.

The fourth level of the energy pyramid represents secondary carnivores. These are tertiary consumers because they are the third organism in the food chain to consume something else.

Food Webs A food web is a diagram that shows how

different food chains connect and overlap. These are used because organisms usually

obtain energy from more than one source.

• http://www.mhhe.com/biosci/genbio/virtual_labs/BL_02/BL_02.html

• http://www.youtube.com/watch?v=De_53QflEXQ

• http://teacher.scholastic.com/activities/explorer/ecosystems/be_an_explorer/map/foodweb_play.htm

• http://www.gould.edu.au/foodwebs/kids_web.htm

• http://www.kidwings.com/owlpellets/flash/v4/index.htm