Understanding Ecosystems Chapter 4

Lesson 1 Vocabulary  Environment — all of the living and nonliving things that affect an organism.  Ecosystem — a community and its physical environment together.  Population — all the individuals of the same kind living in the same environment.  Community — all the populations of organisms living together in an environment.

The tarpon in this photograph are not yet full-grown! These fish don’t become adults until they are between 7 and 13 years old, when they can weigh more than 200 pounds. Tarpon live in salt water, but they can survive in a variety of ecosystems.

Lesson 1 (page 132)  Where do you live? You might name your street and town. You also live in an environment. An environment is all the living and nonliving things that surround you.  The living things in your environment are people, other animals, and plants. The nonliving things around you include water, air, soil, and weather.  The parts of an environment affect one another in many ways. For example, animals eat plants. The soil affects which plants can live in a place. Clean air and clean water help keep both plants and animals healthy.  All the living and nonliving things in an area form an ecosystem. An ecosystem can be very small. It might be the space under a rock. Prairie dogs also live on the prairies and grasslands.

Lesson 1 (page 133)  The small ecosystem found under a rock has nonliving parts, too. They include pockets of air and the soil under the rock. You might find a few drops of water or maybe just damp soil. All ecosystems must have at least a little water.  The ecosystem under this rock has a climate. The climate in an area is the average weather over many years. Climate includes temperature and rainfall. The climate of an ecosystem depends on where the ecosystem is.  An ecosystem can also be as large as a forest. A forest can provide many kinds of food and shelter. This ecosystem may include hundreds of kinds of plants and animals.  Like all ecosystems, a forest has nonliving parts. They include water, air, soil, and climate.