Ecosystems

What is an Ecosystem? An ecosystem is interactions between living and non-living things within a given area.

Components Living things within an ecosystem are also known as biotic factors. Examples include animals, bacteria, fungi, etc Non-living things within an ecosystem are also known as abiotic factors. Examples include sand, water, rocks, etc

An area is an ecosystem as long as you have living components interacting with non-living things. Ecosystems can be very small such as a rotting log or a pond. Ecosystems can also be very large such as the forests in Northern Saskatchewan or the prairies of Canada.

The planet has thousands of ecosystems! Each ecosystem is very different, however, they have one thing in common: They all need a way to bring energy and matter into the system and make them constantly available to living things.

Importance of Ecosystems All things in an ecosystem are important. For example you may want to remove mosquitoes from your life. However insects are a great source of food for birds and fish. If we removed mosquitoes, what would happen to the birds and fish?

Components of Ecosystems Consumers A consumer is any organism that has to seek out and eat other living things for food. Examples include: humans, cats, raccoons, bears, seals, etc

Consumers are classified into three different categories based on the types of food they eat. 1) Carnivores Carnivores eat mostly other animals Examples include hyenas, seals, and cats

2) Herbivores Herbivores are animals that mostly eat plants Examples include moose, elephants, and grasshoppers

3) Omnivores Omnivores are animals who consume other animals as well as plants Examples include bears, raccoons and most humans

Producers Producers are living things who can produce their own food Producers are organisms who provide other energy and matter for other organisms Examples are plants and algae

Consumers depend on producers to provide energy (food) Producers are the beginning of food chains or food webs Food chains are flowcharts which show how living things are connected to each other

Food chains always begin with a producer. Next an arrow points to a secondary consumer. Then an arrow will point to another consumer. Food chains can be very short or quite long.

An Example

Scavengers Scavengers are consumers that don’t usually kill for their own food, instead they feed off of remains of other living things that are killed Examples include crows, ravens, and maggots

Decomposers Decomposers are consumers who break down dead plants and animals Examples include fungi and bacteria

Decomposers are essential to all ecosystems. Decomposers are like nature’s “clean-up crew”. Not only do they break down all living organisms they also provide producers with a continuous supply of nutrients.