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Wonderful Wetlands!
Objectives
After this lesson, students will be able to:
1. Define wetlands.
2. List six different types of wetlands, and describe characteristics
of each.
3. List five functions or benefits of wetlands.
4. Give an example of a typical wetland food chain.
5. Sample a wetland’s plants, soils and hydrology to determine
its type.
What is a Wetland?
Wetlands are characterized by:
• hydrology – water at surface for some part of year.
• wet soils
• water-loving plants (sedges, willow, cattails)
Types of Wetlands
· Marsh - mostly water-loving rushes, sedges,
grasses, and other
plants growing in the water. May dry up in late summer.
· Swamp - mostly water-loving shrubs and
trees
· Pond - open bodies of water less than
20 acres in size, with some
floating vegetation around edges.
· Bog (acidic) – receives only precipitation,
characterized by sphagnum moss and floating mat of vegetation, as
well as, bog rosemary, bog laurel, labrador tea, and black spruce.
· Fen (less acidic and more alkaline) –
receives ground and surface water inflows, characterized by sphagnum
moss, sedges, woody shrubs, and may have floating mat of vegetation
· Vernal pond that results from spring
runoff that eventually evaporates in summer)
Characteristics of Major Wetland Types
| Characteristic |
Swamp |
Marsh |
Fen |
Bog |
|
Vegetation |
trees
large shrubs |
grasses
sedges |
grasses
sedges
shrubs
trees |
mosses
herbaceous
trees
shrubs
|
|
Hydrology
|
Receives
precip & surface and groundwater
|
Receives
precip & surface and groundwater |
Receives
precip & groundwater |
Ombrotrophic*
(fed only
by precip) |
|
Soil
|
mineral
organic (old)
|
mineral |
organic (peatlands) |
organic
(peatlands) |
|
pH
|
basic
neutral (7.0)
acidic |
neutral |
Basic to
slightly acidic
(pH ~ 6.0-9.0) |
acidic
(pH <
5.0) |
|
Trophic
State
|
oligo-eutrophic |
meso-eutrophic |
meso-eutrophic |
oligotrophic |
Wetland Functions
· Act like giant sponges to soak up water, reduce floods,
and recharge groundwater.
· Provide resting place for migrating birds.
· Filter out pollutants, trap sediments, and improve water
quality.
· Provide water, food, protective cover and breeding areas
for wildlife.
· Reduce soil erosion by slowing runoff from storms and spring
runoff.
· Provide nursery areas and protection for fish.
· Supply shade, water, and forage for livestock.
· Act as carbon sinks, helping to keep atmospheric carbon
in balance (reduce global warming).
· Supply agricultural products: cranberries, peat, blueberries
· Provide recreational, educational, and scientific opportunities.
Wetland Functions Activity (Wetland Metaphors in
WOW! The Wonders of Wetlands , p. 85)
Wetlands help
wildlife and people in lots of different ways. Play Put
different objects listed below into a bag. Explain what a metaphor
is. Hand out objects one at a time to groups of 2-3 students, and
ask them to explain how each object represents what a wetland is
or does.
Sponge =
soaks up water, helps prevent floods, adds to groundwater.
Pillow = resting place for migrating birds. Wetlands
are like MOTELS for migrating birds.
Egg beater =
mixes nutrients and oxygen into the water.
Strainer = strains out dirt; keeps water clean.
Coffee filter = filters out pollution; keeps water
clean.
Antacid = takes away (neutralizes) effect of acid
rain.
Wild rice or cereal = provides food for wildlife
and people. Wetlands are like RESTAURANTS
for wildlife.
Soap
= helps clean the environment.
Baby bottle = wetlands are NURSERIES for raising
baby insects (larva) and baby animals
because there are lots of plants for hiding/shelter, food, and water
nearby for drinking.
Wetlands Provide Habitat for Many Plants & Wildlife
List the four parts of habitat?
• food • water • • shelter • space
These must be in the proper amounts and arrangement for each type
of plant or animal, i. e. . too much water v. too little water.
Different animals have different needs for space, i. e. bear v.
ant.
Many different kinds of plants and animals live in a wetland
habitat:
frogs turtles birds beaver alder cattails
tadpoles fish insects moose willow sandhill crane
sedge water lily algae duck weed heron Canadian geese
(encourage students to research additional plants and animals that
live in wetlands)
Food Chains in
Wetlands
Design a food chain for
a wetland:
phytoplankton —
zooplankton — insect larva — frog — heron/snake
Wetland Sampling Activity
Materials/Equipment Needed:
Shovel or soil auger
pH and dissolved oxygen water chemistry kits or probes
Meter stick
Plant ID books
Ziploc bags
Data forms
Procedure
Organize students into groups to:
· Test the pH and dissolved oxygen of the water.
· Describe soil.
· Measure depth to groundwater.
· Identify plants
· Determine wetland type
· Delineate wetland boundaries?
Assessment:
need to add
Summary
Rephrase objectives as questions.
Field Trip Rules:
1. This pond is home to lots of animals.
Treat the pond the way you’d want a stranger to treat your
special place. Don’t walk in it! It makes the water all murky—
hard for us to see critters and hard for them to see their food.
2. This pond
is a nursery for young animals.
Be careful with the animals that you collect so you don’t
injure them.
• Don’t handle them with your hands.
• Put all animals back in the water when you are through.
3. These animals need water.
All collected animals must be placed in a container with water ASAP.
4. Be careful
of equipment.
Rinse all nets and containers when you’re through. Anyone
not being safe and careful with equipment will lose it.
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