Terrariums: A Look at the Living and Nonliving World

Transcription

1 Terrariums: A Look at the Living and Nonliving World Science Materials 2, 2-liter bottles for each student or group of students Razor blade Scissors Moist potting soil Small pebbles or aquarium rock Water in a spray bottle Seeds (a variety of seeds will work, but agronomic or crop seeds are inexpensive, and germinate quickly. Possible seed varieties include wheat, soybean, peanut [raw], popcorn, and bean seeds. These are available from Agriculture in the Classroom [ and/or your local grocery store) Crushed ice (optional) Paper funnel (to be made by students) Lesson Objectives 1. Identify living and nonliving things in a small environment (e.g., terrarium, aquarium, flower bed) composed of living and nonliving things. 2. Predict the effects of changes in the environment (e.g., temperature, light, moisture) on a living organism. 3. Observe and record the effect of changes (e.g., temperature, amount of water, light) upon the living organisms and nonliving things in a small-scale environment. 4. Compare a small-scale environment to a larger environment (e.g., aquarium to a pond, terrarium to a forest). 5. Pose a question about the interaction between living and nonliving things Time: 1 hour, plus daily observation time Grade Level: 3 Standard 2 Students will understand that organisms depend on living and nonliving things within their environment. Objective 2 Describe the interactions between living and nonliving things in a small environment. Background This activity is designed to make each student more aware of how living and nonliving things work together by looking at a terrarium environment and making comparisons to earth systems. By creating a terrarium, students will benefit from a hands-on learning experience over a four week period. This activity will also demonstrate the importance of plants in the world. You may want to begin by allowing your students to go out to the school yard and make two lists one of nonliving things they see and the other of living things they see. Grass, trees, and other plants are the obvious living things. However, if they look closely at the ground they might notice insects, or if they look to the sky, they might see birds. Ask them to note everything they see as living and nonliving. A rock may be an obvious nonliving thing, but clouds, bike racks, brick, etc., should also be noted. Your school may have some wood playground equipment is this wood living or nonliving? The truthful answer would be either nonliving or once living. If the roots and leaves were still attached it would be living. You may need to help students make this distinction. Soil has living creatures in it (the soil may seem alive) but the small rock particles of sand, silt, and clay are rock particles that are nonliving. 1

2 The contents of the terrarium should somewhat mimic earth s living and non living things. Rocks will be added to the terrarium as an important drainage component; the rocks are not living. (Students might like to bring in one special small rock to place in their terrarium on the soil to observe what it does as the plants grow.) Plants on the earth and in the terrarium are living things. They are not only important as human food and shelter or wildlife habitat, but plants are also important in the water cycle (transpiration water evaporating from the plant) and they provide oxygen for other living things like insects and animals, including people. Teacher Notes: Activity Procedures Teacher Preparation For efficiency and safety; cut the 2-liter bottles prior to the activity. Decide if you will have each student create their own terrarium (they will prefer this) or make the terrarium as a group. 1. Remove the label from each bottle and the base, if the bottle has one (most bottles no longer have a base). 2. Cut the bottle base as noted in Figure 1. (Use a razor blade to make you initial incision and then you will be able to use a pair of scissors.) Cut 3 inches (7 8 cm) up from the bottom. 3. Cut the second 2-liter bottle 5 inches (13 cm) from the bottom of the bottle. 4. Poke air holes in the top. Begin with three to four x-shaped patterns of holes, or use a nail to add holes (more holes can be added later if the terrarium appears too wet). 5. Cut three or four 1-inch (3 cm) slits in the open end of the top bottle so it slides into the base. Student Procedures Review the interactions between living and nonliving things outdoors as discussed in the background. Put the children in groups of four and provide each group with a bottle base and top. Or provide each student with a pair of bottles. Instruct student to: 1. Add ¾ inch (2 cm) of aquarium rock to the base. 2. Add 1½ inches (4 cm) of moist potting soil. 3. Provide each student with about 20 seeds (depending on the size of the seed, use fewer seeds if the seeds are large like bean seeds and use more if the seeds are small like wheat). 4. Students should place some of the seeds around the perimeter of the bottle (so they can watch the germination and view roots) and place a few in the middle of the bottle. 5. Cover the seeds with another ¼ inch (1 cm) of potting soil. 6. Water the soil/seeds with a spray bottle, OR place one inch of crushed ice on top of the soil to simulate winter. It is now winter in the seasonal terrarium. Lead a brainstorming discussion about the changes present as winter gives way to spring. As the ice melts, the seeds are watered and the water cycle will become visible to your students. They can also note the changes of the seasons from winter to spring in this seasonal terrarium. Within a few weeks, the warmth and moisture will encourage seedlings to creep cautiously upward. Eventually spring will come to the terrarium with tall, viable plants. 2 Figure 1: 2 liter bottle terrarium bottom

3 7. 8. Place the top on the terrarium carefully. Teachers may want to do this so that in the process of putting the top on the terrarium the contents will not be spilled out. Place terrariums in a sunny location if possible. Explain to the students that they will be checking their terrariums every day and recording any changes on their data sheet. Ask students to look for the following things: What are the seeds doing? On which parts of the terrarium do you see water? Is there anything new happening in your terrarium today? Activity Observations After observing for a week, take the top off of the terrarium (teachers may want to do this to avoid spilled contents) and ask your student to feel the soil, discuss the following: Why is the soil still wet? Do you think that any water has evaporated from the soil? Why? If water evaporated, where did the evaporated water go? Did it ever rain in your terrarium? How do you know? Where did the rain come from? Is there anything in your terrarium that reminds you of a cloud or cloud drops? What conditions in the terrarium help the seed to grow? How is water circulated in the terrariums? Where did the water (that you initially added to the soil) go? Explain. Relate what you see in the terrariums to what happens to water on Earth. Figure 2: 2 liter bottle bottom for terrarium top Vocabulary Contours - Furrow or ridges on the soil surface Indirect light - Light that is reflected from one surface to another Peat - Partly decayed plant material that accumulates wherever water and acidity slows down the process of decay Porous - Possessing pores or holes which allow passage of a liquid Figure 3: Student terrarium 3

4 Terrarium Building Checklist Read and follow the checklist carefully with other members in your group. Create a paper funnel as instructed by your teacher. Then place a check next to each step you complete Place ¾ of an inch (2 cm) of gravel at the bottom of your bottle container. Use a paper funnel to add 1½ inches (4 cm) of moist potting soil. Sprinkle your seeds on the soil, be sure to place some around the edge so you will be able to see the roots. Cover the seeds with ¼ inch (1 cm) of soil. Add crushed ice if you are simulating winter, or water the plants with a spray mister bottle until the soil is moist down to the seeds. Place the lid on your terrarium, you may want an adult s help with this. Place your group s label or your name on the jar.

5 NAME Date Terrarium Data Log (One week after planting) 1. Draw or write about what is happening inside the jar. 2. On which part of the jar do you see water? 3. Is there anything new happening in the jar? Other observations