ECOLOGY

ENERGY IN ECOSYSTEMS

Ecology is the study of how organisms live and interact in their environment. The term ecology literally means “study of the household” so if you are studying the ecology of fish, you are studying fish neighborhoods!

Community and Habitat

A habitat is a particular place where organisms live. Forests, ponds or coral reefs are all examples of a habitat. Your backyard can be a habitat.

The organisms in the habitat are community members. These organisms are community members of a pond habitat.

Community and habitat

The habitat is like a neighborhood.

The community is like the people.

ECOSYSTEMSAn Ecosystem is made up of groups of organisms and their physical environment.

Environment is everything living and nonliving that surrounds an animal.

Can you name some of the things in this bears environment?

ECOSYSTEMS

Living things depend on each other for energy. Plants get their energy from the sun, some animals get their energy from plants, and others get their energy from other animals.

ENERGY IN ECOSYSTEMS

Most of the energy in an ecosystem comes from the sun. Organisms called producerstake in that energy and store it in their cells. You have already studied that process, it is called photosynthesis.

Producers include plants, some bacteria and algae. See some on the next slide!

PRODUCERS

ENERGY IN ECOSYSTEMS

Everything else in an ecosystem is called a consumer. Consumers get their energy by consuming other organisms. They can’t make their own food.

In an African Grassland habitat, Acacia trees are producers, and giraffes and lions are consumers.

CONSUMERS

There are 3 main groups of consumers:

ENERGY IN AN ECOSYSTEM

In every ecosystem there are also some consumers known as decomposers. Decomposers get their energy by consuming wastes (fallen leaves, dead bodies, feces). In an African Grassland habitat, dung beetles and fungi are the decomposers.

ENERGY IN AN ECOSYSTEM

Consumers are sometimes separated into levels. First level consumers are animals that eat producers. These are herbivores.Second level consumers are either carnivores or omnivores and they eat first level consumers.Third level consumers eat second level consumers.

See the next slide to learn more about the different levels of consumers.

2ND LEVEL CONSUMER

ECOSYSTEMS Can you identify….

The producer? Grasses

The first level consumer? Cricket

The second level consumer? Frog

ENERGY IN AN ECOSYSTEM

Energy flows from the sun to the producers to the consumers. This path is called a FOOD CHAIN

Producer1st level consumer

2nd level consumer

A food web looks at many more parts of the ecosystem. It shows how several animals interact with each other. In food chains on earlier slides we looked at only trees, giraffes and a cheetah. But there are many more producers and consumers in the African Savannah.

A food web shows how the cheetah can consume more than just a giraffe, and that there are more than just trees as producers. It is more complex.

Can you follow what eats what?

BALANCE IN THE ECOSYSTEMA problem in one part of the food web can cause problems in all of it. Imagine what would happen if there were no trees in this picture. What would happen to the giraffes? What would happen to the lions?

BALANCE IN THE ECOSYSTEM

This is why all of the planet’s resources are so important. We must learn to respect nature and not upset the balance through human activities.

BALANCE OF THE PLANET

Afterall, man is just one small part of the planet’s giant ecosystem. Learn more about this in your next module on Cycles of Matter.

SUMMARY SLIDEEcology is the study of organisms and how they interactEcosystems include organisms and their surroundingsOrganisms can be producers or consumersProducers are mainly plants, algae and some bacteriaConsumers can be herbivores-plant eaters, carnivores-

meat eaters, or omnivores-eat plants and animalsThe relationship between producers and consumers is

shown in either food chains or more complex food websThe relationship between organisms and energy is

shown in a food pyramidDisturbances in a food web can cause problems in the

entire ecosystem