📚 Study helper: This page helps you learn and practice for school. Read it, listen to it, and try to say the three jobs in order!
An ecosystem is all the living and non-living things in one place.
The living and non-living things work together.
Plants are living things.
Animals are living things.
Sunlight is a non-living thing.
Soil is a non-living thing.
Here is how an ecosystem works.
Pick your grade:
Elementary: What an Ecosystem Is
Think of an ecosystem like a puzzle. All the pieces fit together.
A forest is an ecosystem
A forest has trees and ferns. It has soil. The soil and the weather help the plants grow. Animals use the plants for food. Animals use the plants for shelter, too.
A pond is an ecosystem
A pond has plants and animals. They live together in and around the water. Scientists can draw a pond food web. A food web shows who eats what.
Everything is connected
Each part of an ecosystem has a job. If you change one puzzle piece, you get a different puzzle. Change one part, and the whole ecosystem can change.
Three jobs in an ecosystem
Count the jobs with me. One, two, three!
Job 1. Producers make food
Plants are producers. Plants use sunlight to make their own food. That food is a kind of sugar.
Job 2. Consumers eat food
Consumers eat plants. Consumers eat other animals, too. Animals are consumers.
Job 3. Decomposers clean up and recycle
Decomposers recycle parts of dead plants and animals. Good parts go back into the ecosystem. Tiny living things called bacteria are decomposers. Fungi are decomposers. Earthworms are decomposers, too.
Animals can help make an ecosystem
Beavers build dams.
The dams create wetlands.
Birds spread seeds.
The seeds help new plants grow in new places.
Middle School: What an Ecosystem Is, With More Detail
An ecosystem is made up of all of the living and non-living things in a geographic area.
Plants, animals, soil, climate, and other features of the environment interact with each other to form an ecosystem.
Scientists use the words biotic and abiotic for the two kinds of parts. Biotic parts are the living parts. Abiotic parts are the non-living parts.
The United States Geological Survey lists puzzle pieces like sunlight, temperature, precipitation, elevation, vegetation, wildlife, microbes, and soil. Change some pieces, and you end up with a different ecosystem.
Two main types, and two more places
There are two main types of ecosystems. Terrestrial ecosystems are found on land. Aquatic ecosystems are found in freshwater or the ocean. The sky is an ecosystem too, where flying insects, birds, and mammals interact with the atmosphere. Underground caves and aquifers are ecosystems too, home to animals adapted to live underground.
An estuary is an ecosystem
Estuaries are bodies of water and their surrounding coastal habitats, typically found where rivers meet the sea. Their waters are brackish — a mixture of fresh water draining from the land and salty seawater. Estuaries are some of the most productive ecosystems in the world. Many animal species rely on estuaries for food and as places to nest and breed.
How food energy moves
Energy from the Sun provides heat, light, and food for organisms on Earth.
Producers
Producers are plants, algae, phytoplankton, and other microorganisms that use photosynthesis to convert energy from sunlight to sugar. Without producers, most life could not exist on Earth.
Consumers
Consumers are organisms that eat plants and other organisms. A person can be a primary consumer or a secondary consumer, depending on what the person is eating. Food energy then cycles from producers to consumers.
Decomposers
Decomposers are organisms that recycle nutrients through the ecosystem. Examples are bacteria, fungi, and earthworms. Without decomposers, the ecosystem could not function. Energy and matter get recycled through ecosystems over and over again.
Food chains and food webs
A food chain follows food energy in a line, from producers to consumers and then to decomposers. A food web is bigger. Many food chains connect in one place. Students in a Smithsonian grade 5 module develop and use food web models to track matter and energy flows in ecosystems, and the module uses a simplified food web of plants and animals in a pond environment.
Why healthy ecosystems matter to people
Healthy ecosystems provide us with food, energy, building materials, medicine, clean water, and clean air.
They support biodiversity. They also help with soil erosion, flood control, and carbon storage.
The benefits that people obtain from ecosystems are known as ecosystem services.
The National Oceanic and Atmospheric Administration says ecosystem services are the benefits nature provides to people, and that estuaries provide water filtration and habitat protection.
Words to Know
Ecosystem: An ecosystem is all the living and non-living things in one place, working together.
Producer: A producer makes its own food. Plants use sunlight to make food. That food is a kind of sugar.
Consumer: A consumer eats plants or eats other animals to get food.
Decomposer: A decomposer recycles parts of dead plants and animals. The good parts go back into the ecosystem.
Photosynthesis: Photosynthesis is how plants and some other producers use sunlight to make sugar for food.
Food web: A food web shows many connected food chains in one place. It shows who eats what.
Food chain: A food chain follows food energy in a line, from producers to consumers and then to decomposers.
Ecosystem services: Ecosystem services are the benefits nature provides to people, like clean water and clean air.
📚 Study helper: Great job! Now try this. Cover the three jobs. Can you say them in order? Producer, consumer, decomposer. Then name one living thing and one non-living thing in a forest. Then check your answer.
Sources
U.S. Geological Survey — Ecosystems: https://www.usgs.gov/science/science-explorer/biology/ecosystems
U.S. Geological Survey — Ecosystems like a Puzzle: https://www.usgs.gov/media/images/ecosystems-a-puzzle
NASA Science — Big Idea 2.1, Intermediate Level Guiding Question: https://science.nasa.gov/big-idea-2-1-intermediate-level-guiding-question/
Smithsonian Science Education Center — How Can We Predict Change in Ecosystems?: https://ssec.si.edu/ecosystems-phenomenon
Smithsonian Science Education Center — STCMS: Ecosystems and Their Interactions: https://ssec.si.edu/node/935
NOAA National Ocean Service Education — Estuaries Tutorial: https://oceanservice.noaa.gov/education/tutorial_estuaries/
NOAA National Ocean Service Education — Ecosystem Services: Estuaries Tutorial: https://oceanservice.noaa.gov/education/tutorial_estuaries/est03_ecosystem.html