EcosystemsEcosystems

What is an Ecosystem?What is an Ecosystem? An ecosystem is a plant and animal An ecosystem is a plant and animal

community made up of living and community made up of living and nonliving things that interact with each nonliving things that interact with each other and their environmentother and their environment

An ecosystem is a unit of independent An ecosystem is a unit of independent organisms which share the same habitat.organisms which share the same habitat.

““eco” means house, habitat, environmenteco” means house, habitat, environment Ecosystems can be permanent or Ecosystems can be permanent or

temporary.temporary. Ecosystems usually have several Ecosystems usually have several

different food webs.different food webs.

What is ecology?What is ecology?

Ecology is the study of living things Ecology is the study of living things in relationship to each other and in relationship to each other and their natural environment their natural environment (surroundings).(surroundings).

FoodFood ShelterShelter ProtectionProtection ReproductionReproduction

Our EnvironmentOur Environment

Our environment includes both Our environment includes both living and nonliving organisms.living and nonliving organisms.

Living:Living:

plantsplants

animalsanimals

insectsinsects

Nonliving:Nonliving:

soilsoil

waterwater

airair

sunlightsunlight

What do all living things What do all living things need in order to survive?need in order to survive?

SunlightSunlight

WaterWater

FoodFood

What is a food chain?What is a food chain?

It shows how each living thing gets its food. It shows how each living thing gets its food.

A food chain always starts with a green plant, which is a A food chain always starts with a green plant, which is a producerproducer.. … …which is eaten by an animal, called a which is eaten by an animal, called a

consumerconsumer.. … …which is sometimes eaten by another animal, called a which is sometimes eaten by another animal, called a consumerconsumer.. … …which is sometimes eaten by another animal, called a which is sometimes eaten by another animal, called a consumerconsumer..

(The animal at the end (top) of the food chain is called a (The animal at the end (top) of the food chain is called a predatorpredator.).)Eventually the animal dies and its body is broken down to become soil Eventually the animal dies and its body is broken down to become soil

again by a again by a decomposerdecomposer..

All living things need food All living things need food to give them the energy to to give them the energy to grow and move.grow and move.

Here is another food web. It shows who Here is another food web. It shows who is eating who. The arrow means “is is eating who. The arrow means “is eaten byeaten by””

Grass ----> Grasshopper --->

Toad ----> Snake ----> Hawk

Grass is eaten by Grasshopper is eaten by Toad is eaten by Snake is eaten by Hawk

What are producers?What are producers?

All plants are producers.All plants are producers.

Plants make, or produce, their own Plants make, or produce, their own food through food through photosynthesisphotosynthesis..

What are Consumers?What are Consumers?

Animals that eat the plants are Animals that eat the plants are consumers.consumers.

There are different kinds of consumers, There are different kinds of consumers, depending on what they eat.depending on what they eat.

*herbivores*herbivores

*carnivores*carnivores

*omnivores*omnivores

*scavengers*scavengers

Herbivores eat Herbivores eat only only plantsplants..

Carnivores eat Carnivores eat only only animalsanimals..

Omnivores eat Omnivores eat plants and plants and animalsanimals..

Scavengers eat Scavengers eat dead dead animalsanimals..

What are decomposers?What are decomposers?Decomposers are the bacteria and Decomposers are the bacteria and

fungi that break down waste and fungi that break down waste and dead plants and animals, returning dead plants and animals, returning them to the soil.them to the soil.

Earthworms also belong in this Earthworms also belong in this category, since they break down category, since they break down soil.soil.

What’s the difference What’s the difference between a food chain and a between a food chain and a food web?food web?

A food web consists of many food chains.A food web consists of many food chains.

A A food chainfood chain only follows one path as animals find food. only follows one path as animals find food.

Example: A hawk eats a snake, which has eaten a frog, Example: A hawk eats a snake, which has eaten a frog, which has eaten a grasshopper, which has eaten grass.which has eaten a grasshopper, which has eaten grass.

A A food webfood web shows many different paths to show how shows many different paths to show how plants and animals are connected.plants and animals are connected.

Example: A hawk eats a snake, but it might also eat a Example: A hawk eats a snake, but it might also eat a mouse, a squirrel, a frog, or some other animal. The snake mouse, a squirrel, a frog, or some other animal. The snake may eat a beetle, a caterpillar, or some other animal. And may eat a beetle, a caterpillar, or some other animal. And so on for all the other animals in the food chain.so on for all the other animals in the food chain.

A food web is several A food web is several different food chains different food chains connected together.connected together.