What is a Wetland?
are all the Wetlands?
for the Future
will be able to:
typical pollutants of waterways.
how wetlands remove these pollutants.
- Explain why
wetlands are essential to clean water.
simulate the movement of pollutants into and through a wetland.
- large outdoor
- paper grocery
bags, 6-7; cut them to one-half their normal height
- dozens of
objects about the size of a tennis ball (balls of any kind, half-pint
milk cartons, individual yogurt containers, sponges, wads of paper)
enough to fill each bag to overflowing
for the 3 Roles: Water, Soil, Plants
Science, Earth Science
communication, comparison, discussion, inference
at least 20 students
CONCEPTUAL FRAME WORK
III. Wildlife and Ecological Systems
contaminant, load, pollutant, sediment, wetland
Chapters One, Two, and Three Hold The Load
water moves through agricultural and urban land, it picks up many
contaminants. Examples include excess phosphorus and nitrogen, which
are components of fertilizers used on croplands and on lawns; and
sediment. When a stream is cloudy due to extra sediment, it is said
to be carrying a "heavy sediment load." These contaminants wash
into waterways during storm events, floods, and through normal irrigation
and other types of watering. Wetlands play an important role in
reducing the load of contaminants in water. As a stream or river
flows into a wetland, the dense vegetation slows the water. As water
slows, sediment and contaminants settle out. Wetland plants absorb
some of these contaminants and wetland soils neutralize others.
Water that flows out of a wetland is cleaner than when it came in.
But as it continues through its cycle, it will undoubtedly pick
up more contaminants and carry those contaminants until it flows
through another wetland.
- Discuss types
of pollutants- nutrients, metals, etc.-that might occur in a stream
or lake . (Do not discuss wetlands; this is part of the last step
of this activity.)
- Explain the
term "load," which is a term used to describe the amount of pollutants
in water. (See background for an explanation of this and other
- Explain that
each of the dozens of objects in the paper bags represent a type
- Make sure
the bags are overflowing with "loads."
- Mark an
area at least 30' x 60' outdoors. Tell the students that the area
within the boundary is a lowland. The area outside the boundary
is an upland.
- Ask 6-7 students
to be water; 2 to be soil. The rest will be plants.
- Post the
rules for each position (Load Role Rules)
, and make sure the students understand the rules for each
position, not just their own. (One way to do this is to have each
group of players explain their rules to the entire group.)
ONE: Ask the plant players to observe this round. Ask the
two soil players to enter the lowland. Position the water players
in the upland and instruct them to run through the lowland three
times. (Make sure the students run! Their loads should spill out.)
When all the water players have completed their runs, assemble
the students and record the amount and locations of the loads.
TWO: Ask half the plant players to position themselves in
the lowland. Return the soil players to the lowland. This time,
instruct the water players to walk through the lowland three times.
Repeat the evaluation at the end of the round.
THREE: As per Round Two, but with all the plants in the lowland.
9. List two
or three questions about this activity so that all students can
see them. (See Sample Questions).
The questions provided can also help guide the discussion in the
10. Ask the
students to divide themselves into three groups and discuss the
questions you have listed and to list five more questions of their
own about what happened in this activity.
and discuss the questions. Introduce the concept of wetlands.
Give the students
15 minutes in their small groups to devise a way of explaining what
happened in this activity. They can sketch out a poster, outline
a narrative, record a mock interview, etc.
1. Apply the
principles of this activity to a wetland in your area.
2. Have students apply the principles of this activity to one of
the major types of wetlands.