A Great, Rotten Idea
- Adapted from Recycling Study
Guide, by Hallowell et al., Wisconsin Dept. of Natural Resources
to Trash Goes To School
- GRADE LEVELS:
- SUBJECT AREAS:
About 30% of our solid waste is valuable biodegradable material
that can be used to improve soil.
To have students investigate the pros and cons of composting.
leaves or food scraps
microscope or hand lens
decomposition, biodegradable, fungi, bacteria
When we mention "recycling," we often think of recycling
glass bottles, aluminum cans, and newspaper. But another 30%
of the household garbage we throw out also can be recycled. These
recyclables are food scraps, leaves, grass clippings and other
biodegradable organic wastes. Organic waste can be recycled by
composting. Simply stated, composting creates optimal conditions
for decomposition to occur. Decomposition is the biochemical
process by which bacteria, fungi and other microscopic organisms
break organic "wastes" into nutrients that can be used
by plants and animals. Decomposition occurs in nature whenever
a leaf falls to the ground or an animal dies. The results of
decomposition in a compost pile is a nutrient-rich humus that
is excellent for improving soil quality and plant growth.
1. Define: recyclable, biodegradable.
List items that are recyclable and/or biodegradable. Discuss:
- Are there recyclable materials that
aren't biodegradable? (e.g., aluminum.) Are there biodegradable
materials that aren't recyclable? (e.g. food scraps).
- 2. Feel, smell, and look at the rotting
log, grass clippings, leaves or food scraps. What words would
you use to describe these materials? List these words. Do the
words have positive and/or negative connotations? Why?
- 3. Explain what is happening to the
rotting material. Discuss:
- What is the natural process that breaks
biodegradable material into particles that can be used again
by plants and animals? (decomposition)
- What organisms assist in this decomposition
process? (fungi, bacteria, earthworms, springtails, mites,
etc.) Take a look under a microscope to find out what you
cannot see with the naked eye.
- What will your rotting material finally
- 4. Imagine a world where decomposition
doesn't take place. Discuss:
- What would happen to organic materials
like dead animals, leaves or sewage?
- Could plants and animals survive if
decomposition didn't occur? Why or why not?
- Is decomposition important? Why?
- 5. List items you throw away that are
- How might you and your family recycle
- What is composting?
Why do you think people compost household organic wastes?
- 6. What are some benefits of composting
household food and yard wastes? For example:
- - doesn't require the purchase of expensive
plastic bags often used for disposing household and yard wastes.
- - saves the cost of transporting wastes
to and handling wastes at the landfill or incinerator.
- - reduces pollution from landfill (leachate
and methane gas) or incinerator.
- - creates nutrient-rich humus you can
use to improve the texture of your yard and garden soil; saves
money you might spend on mulch.
- 7. What are some possible problems
with composting? What suggestions do you have for solving the
problems? For example:
- It's too much work. (Mowing the
lawn and washing the car are work, too, but we choose to do these
activities because they're satisfying - so is composting! And
composting has a positive impact on the environment, which can
make us feel good.)
- You'd have to run outside everytime
you eat an apple or peel a potato. (Just place the scraps
into a plastic container with a lid. Keep the container in or
under the kitchen sink, then take the waste to the compost pile
whenever the container is full.)
- There's not enough space. (Share
a compost pile with neighbors, and encourage the town to collect
and compost yard wastes from people who don't have enough space
for a compost pile of their own).
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