Wading Into Wetlands

NaturelFraoks
Wadin
$
lnto Wetla nd
Studentswill be obleto...
. understondthe functions of wetlonds
. learn speciolodoptotionsof both plontsondonimolswho
moketheir homein the Reserve
. understondhow woter guolity offects wetlonds
Resourcesincludedin this packet:
- generalinformqtionaboutwetlonds
l. "FreshwcterMorsheso
"Wetlonds
- lists benefitsandccusesof
Resources"
2.
ore Voluoble
wetlonddegrodotion
"A
plcnts,
3.
Spotter'sGuidefor WetlondVisitors"- listspossible
onimols,insects,etc thqt conbe foundin o wetlond
"Treatment
howplantsobsorb
Plonts"- lessonfhot demonstrotes
4.
pollutonts
- lessonthot usescommonobjects to
5. "Wetlqnd /tAetaphors"
explointhe vcriousfunctionsof wetlonds
Makethe mostof yourvisit....
songbirds
like mosquitoes!
boots,ondinsectrepellent.Remember,
Bringbinoculors,
. Don'tpickplcntsor eot berries...ond
don'thandleonywildonimolsl
. Stoyonthe boordwalk
or troils to ovoidtromplingdelicoteplonts
qll
. Pick-up
will try eotingonything...once!
ondthrowowoy trosh.Animols
Heckrodt Wetland Reserve
locoted of 13()"5PlonkRood, tlAenosho,WI 54952
For info coll: 920-720-9349
AdditionolResources:
1. "Wetlqnds" - U.S. EnvironmentolProtection Agency
httPz/ / www.ePa.gov
/ owow/ w etlands
Vost informotion with links for educotorsthot contoinoctivities
?. "Wetlondsof Wisconsin"- WisconsinWetlond Association
hth ://unvw.wiscwetlonds.orglwetlondslhtmI
&nersl information obout wetlonds
http ://vnrw.rriscwetlonds.org/resources.htm
I
Contoinslinks to tencher resources
3. "Hobitct Guide:Wetlond LifeZone'- NotionolWildlife Federotion
htlp://ww.enafure.com/outdoorsloutdoors home.osp
&neral infornotion on wetlonds.Also enoture.comcontoins grerrl field
guideswith pictures ond informctionobout plonts,onimols,ond insects.
4. DucksUnlimited
httP ://wurw'ducks'org
Contoinswaterfowl identificotion,getnerd wetlond informofion, educotor site
with resource moteriol, and links to the student "Greenwitgs"ge
5. PondLif e - GoldenGuide. by GeorgeK. Reid,Ph.D
6. Project Wild Agugtic
7. Prgiect Wet Curriculumond Activity 6uide
8. RonqerRick'sNoture Scope:Wodinqfnto Wetlqnds
9. b!/eflands,lUonderlands-Wf Dept. of Mturql Resources
10. WOW - The Wondersof Wetlands: An Educotor'sGuide
FNESHWATER
WETLANDS
here'sa duck factoryin the Midwest.No, it's not a huge assemblyline
that pumps out plasticducklings.It's a marshywetland area, better
known as prairie pothole country, that covers more than 300,000
square miles (780,000 kmz) throughout parts of the Dakotas,
Minnesota, Montana, Iowa. and Canada. Millions of ducks-from mallards to
ruddy ducks-start their lives here, as do thousands of geese,shorebirds,and
other types of wildlife. Becauseof its incredibleproductivity,many scientistsconsider this prairie pothole region to be one of the most important wetland areasin
the world.
In this chapter we'll focus on prairie potholes and other types of freshwater
marshes.We'll also take a look at swampsand bogs and at the characteristics
that
make all freshwaterwetlandsunicue,
Some scientisfs estimate that more than 50 percent of the wild ducks in
North America depend on the prairie pa,thole region.
MARSHES
I[illions of lvlarshes: From small cattail marshesalong major highways in
Californiato hugeexpansesof sawgrass
in Florida,freshwatermarshesire a common sight throughout much of North America. Accordingto some biologists,
freshwatermarshesmake up abohrt90 percentof our wetlands.
As in othertypesof wetlands,the waterin a marshoftenfluctuatesfrom season
to season,risingduring heavyrainfallsand often disappearing
duringdry periods.
But you can usually tell a marsh from other types of freshwaterwetlands by the
type of vegetationthat growsthere.Thick clumpsof soft-stemmed
plantssuth as
grasses,sedges,and rushesare abundant.And cattails,waterlilies,smartweeds,
arrowheads,and other non-woodymarshplantsare alsocommon.
Types of lvlarshes: It's hard to generalize
about freshwatermarshes,but some
scientistshave lumped them into threegeneralgroupsor zones:
o DEEP MARSHES are usually flooded every year, exceptduring extreme
droughts.The watercanbe up to fourfeet(|.2 m) deepduringwet periods,and
there are often areasof open water.Deep marshesare usuallyfound near the
edgesof lakes,ponds,and rivers,but alsoform in deeperpotholes.Mostarefed
by rainfall,storm runoff, and meltingsnow.Cattails,bulrushes,waterlilies,and
duckweedare commondeepmarshplants.
o SHALLOW MARSHESare often found next to deep marshes.They are less
regularlyand less deeply flooded than deep marshes,and the water level is
usuallyonly six inches(15 cm) to a foot (30 cm) deep.Grasses
and sedgesare
common shallowmarshplants,as are smartweeds,cattails,and bur reeds.
. WET MEADOWS flood annuallyand their soilsmay be saturatedwith water
year round, but the water never getsdeep. Many water-lovingmarsh plants,
such as sedges,grasses,
rushes,and wetlandwildflowers,are common.Wet
meadowsform in poorlydrained,low-lyingareasand alongstreamsor lakes.
Nofe; Many marshyareas,suchasthe prairiepotholeregionmentionedin the
introduction,have a combinationof thesethreetypesof marshes.
( cotlttnue(.l next page )
33
"Teeming with wildlife" is an accuratedescriptionof
Life Support Systems:
think that somemarshesarethe
manv freshwater*utinnt. In fact,miny scientists
food, shelter,and water for
provide
i;;;it;tr "; eartn. Marshes
ffir?;il;;;
mammals,
foryoungfish,birds,insects,
i"X"i""rtiiJrl,;;e theyactasnurseries
reptiies,and other animals.
BOGS
-are' and water.Thesethreewordscharacter2emany of
ForPeats soke: Peat,acid,
fresnwater wetlands that usually contain a huge
the world's bogs. BG
of partiallydecayed
build-up of peat-ih 5rganicmaterialthat is made up mostly
p""il;;!as
plants die and their leaves,stems,roots, and other
;il;],,'!i"ti"f.
Ot;t ti-", this acid-richmaterialis compressed,.forming
oarts fall into the;;;;.
(12
i; somebogs,lhe peatcanbe over4o feet m)thick'
ihil1l;;;&;i.
"'
inwetareas
of theworld.They_form
ui,iayto"nd in theJoidetregions
#;';
The rate of dewhere there i, u"rvlittt" water flowing i-nor.out of the wetland.
grows
peat
laver
the
so
vearafte.ryear'
slol,tr,
i; td"g is exnemely
;;ilL;;
andthelimited
temperatures,
iiii.j-r,ut-i.iiitv "tin" p"it, tn"'.old year+ound
discouragebacteriaand other de-
au" to pb"t water circriation
;;;;irppb
."iip"tot' from breaking down plani material')
of this slow rate of decomposition,plants and
no'fr"oturr"lgA"i"
Buried -tfi"i
i"fi into U"gr often stay well-preservedfor thousandsof yegrs'
ffi;;[
and other'plant
S.i"rGtttruu" ddi;1" b& bottomsto nna ancientpollen,leaves,
animal parts from prehistorictimes' They've
oarts. as well * pil".tlyE"t"*ea
n,i-u" bodies,with hair, mgsclep,and teeth intacl
;;;;'f*;e;;;t"t"
buried sediments,such as
Scientistshave also U""n able to find and anal]v?je
they have
radioactive fallout and tt"uw -"tuls. By studyrnglayered bog re.mains,
"i intorrnuuoniUout how climaies,vegetation,and landscapeshave
;;;a-t"g"tt
changedover time.
bogs is coveredwith a floatingmat of
duo'*ln' ond Sh-okin': The water in many forming when sphagnummossinbogs, the mat stirts
tiiil u"g"tation. fn *-"
the open water'
r"J"t tf,e tangleJ rnu* of iquatic plants that have grown in
nJtptusnumgrows intoa mossymat andsometimesthe entire bog
i;;;t"Uy
tpfrugnu- also actsai a substate for other plants. ln time,
becomes-rp"t"i.fi"
and tamarack,will grow on the thick mat..lf vou
bhi-tdce
il.[;;
;;';;;;,
with each step'
walk on this mossy @rpet, you can often feel it quiver and bounce
plant roots, and peat undemeathgves the
The interconnecdd-;;i;f'rphugn.t.,
u"*"re the entiie u"9etatiu" massfloatsin the water like a huge
G ilffin."
sponge.
'ii'il-'po"t:
Many bogsin Ngrth Arnericacan thank glaciersfor their start.About
reteated, they left many glacial
10,000 years "g",'*n"-r ih" lutt of the glaql-er9
when huge
lakes behind. fn tt." *eas these lakes,calle! keftle holes,formgd
formed
others
melted.
rc"-it"ihad been buried underground
ffi.k-;i;l".i"r
(some
also
bogs
when shallowbasinsr"tt uv the rebeatingicefilled with rainwater.
)
i91ni1; ;ghciated, poorf*yatuined lakebedsand depressions.
adaptedto high
ire-specially
bogs
livein
that
phnts
Life inthe fog:-lial' .iin"
bog plants,
Some
substate.
a
soggy
acidity,low oxygenuni nutient supplies,and
to dealing
adapted.
well
speciafiool systemsth.a-iare
such as black rfi;;,-d;e
as some
with low o*yg"n *pplies and waterlogbed.conditions'Others, such
helps
orchids and heaitrpiJntr, have symbiJti relationshipswith fungi,.*lli9h
bladderworts,
as
plants,
such
bog
many
itr"t" g"t tt e n,rtie'nts ih;V need.And
pit.n"ipfunts, and sundeuis,get some of their foodin a very unusualway-they
irap and digestinsectsand other tinv animals'
animalsare not
Bogs also ,,rpp"Ji*u ua "-ui".rj of wildlife, although many
bears, and other large
full_time bog re-sidents.For example, moose, dg,e1,
shelter,and water'
mammalsvisitbogi at varioustimesof ihe year to find food,
34
Don't G-et"Bogged Down".'The word bog meansdifferentthingsto different
people. In some parts of the world, it is used only when refening to acidic,
sphagnumwetland,s.In other placesit is usedto describeany type of wetlandthat
haspeat deposits.(Many scientistsusethe more generalwordpeatlandtodescribe
a wetland that has peat deposits.And they considerbogsto be one t5pe of peatland. Fens,calTs,and even someswampsand salt marshesare also consider'edto
be types-ofpeatlandsbecausethey containpeat deposits.) In this issuewe are generally refening to acidic,sphagnumbogs when we say the word "bog."
SWAMPS
Swamp Stories: Poisonoussnokes hangt'rom the trees. Quicl<sandis around
euery.bend. once you get lo.st,you'll neier find your way out. Consideringthe
abundance of these and other m5fths,it's no wonder that many people f,ave
stalge ideas about swamps.But-most spooky swamp images 6ave been the
product of imaginativewriters,and have iittle io do wiin reaity. Yes, there are
poisonous snakesin some swamps, but most don't climb or hang from hees.
Quickand occursin some swampyareas,but it's not very.o--on."And you are
ju*.as likel.y.toget lost in a desert,forest,or other habita[as you are in a jwu-p.
The tuth is that swampsare someof the most fascinatingind diversewetlands
in the world. And they-ale Lo more dangerousthan other 6p"r of habitats.From
the.cypressswampsof the Big Thicket i-nTexas to New Jeir"y's GreaiSgrurnp,
'
"
each has its own characterand unique plant and animarlife.
Down in the Swamp: So what makes a swamp a swamp? Scientistsdefine
swampsas weflands that are dominated by shrubs or hees. They are usually
saturatedwith water during the growing seain, but may dry
-orout iniate summer.
Swarnpscan have anywhere from a fZw inches to a foot
more of water. In
northem swamps red maple, black willow, northem white cedar, alder, and
cottonwood are some of the more common bees. In southemswampsthe forests
are made up of such treesas water oak, tupelo, and bald cSpress.And in some
swampareas,where shrubsarethe most-dominantplants,you;[ find water willow,
pussywillow, leatherleaf,inkberry,andbuttonbusi $owing in the mucky soil.
Types 9! Swqmps.' There are manv different types of freihwater swarips, but
most fall into thesetwo generalgroups:
o FORESTEDSWAMPS are often associatedwith major river systems,such as
the Mississippi,a.ndthey oftenoccuron riverfloodplains.Many of theseswamps
are famous for their huge_tees,and contain standsof enormous bald cypress,
overcupoak, and tupelo. Mostforestedswampsare subjectedto periodii iloodrlgglqugually stay wet during most of the year.
o SHRUB SWAMPS in North America are characteized by scrubby, lowgrowing-vegetation.Some of theseshallowswampsare wet for only part of the
year and often dry out du-nnghot, dry summers.Thereare many differenttypes
of shrub swamps, from boggy, boreal swamps in the north called heathi to
shrubby coastal-swamps
in the southeastcalledpocosins.Shrub swampsoften
form in poorly drained areason the edgesof lakes,forestedswamps,marshes,
and sheams.
Zoo in the Goo: Swampsare incrediblydiverseand supporta wide variety of
animal life. Many swamp critters,such is alligatorsand-cottonmouths,are especiallyadaptedto the murkyenvironmentof a iwamp. But othersthat usuallylive
in upland areas,suchas panthers,foxes,bears,and iaccoons,often wanderinto
swampsto find food, shelter,and water. (See"Gator Hole Graphics"on page40
for more about life in a swamp.)
35
(t)
Wetlnndscr,reVahnblc ffi
B,eso.twees
,.\ll
lLtL!)
Duckweed
_,$#H
-zv)V,'|!X'itY
Theg:
* gnooidc
tut
flaod gnoteefron
* aet as frltqs, etilwttcing
watu qualitg
* gwoadde restitr,lg pl,a,ees
birds
for migrating
* prouidc nestfiltg plo,ees for
a oarietU of wdld,lfrfe
* are lwmo to marry plolnts,
inseets, fish, birds and
matnmals
Leopardfrog
Primary
Coluses of Wetlmtd
Loss and lDegradafrort
lluman Impacts
* prooidc
peoplc.
reereation
Natural Threats
o
drainage
o
erosion
o
dredging and stream channelization
o
subsidence
o
deposition of fill material
o
sea-levelrise
o
diking and damming
o
droughts
o
tilling for crop production
o
hurricanesand other storms
o
grazing by domesticated animals
o
overgrazingby wildlife
o
discharge of pollution
O
mining
o
alteration of hydrologi (water flow)
_Source: U. S. Enlironmental
Protection Agerrcv
for
A SPOTTER'S
GUIDEFOR
\ATETIANID
VISITORS
Look for theplants and animalslisted below in the wetlandsyou visit. Somecommonspeciesmay be seenin severaltypes
of wetlands.
Using one of the wetland 6eld guides suggested,seehow many differentplantsand animalsyo., ."., identify.
MARSHES
Plants
Cattail
Arrowhead
Bluejointgrass
Bulrushes
Sedges
Water lily
Pondweed
Birds
Americanand leastbittems
Swampsparrow
Blue-wingedteal
Canadagoose
Great blue heron
Marsh or sedgewren
Pied-billed grebe
Great egret
Red-wingedblackbird
Sandhill crane
Black tem
Virginia and sorarails
Yellow-headedblackbird
Mammals
Masked shrew
Meadow vole
Muskrat
Mink
Beaver
White-taileddeer
Reptiles and amphibians
Spring peeper
Bullfrog
Northem water snake
Paintedturtle
Insects and butterfies
Milkweed beetle
Damselflies
Dragonflies
Viceroy butterfly
SWAMPS
The plants and animals found in
swamps(wetlands with trees
and shrubs)vary widely from
north to south in Wisconsin.
Northem (N) and southem (S)
speciesare labeled accordingly;
unlabeledspeciesare found
throughout the state.
Plants
Marsh marigold
Red osier dogwood
Skunk cabbage
Speckledalder
Spottedtouch-me-not
Red and silver maple (S)
Black ash (S)
Hemlock (N)
White cedar (N)
BirdE
Woodpeckers
Belted kingffsher
Alder and willow flycatchers
Yellow warbler
Black duck (N)
Wood duck
Barred owl
Sandhill crane
American woodcock
Common yellowthroat
Red-shouldered
hawk
Great blue heron
Northem oriole (S)
Prothonotarywarbler (S)
Mammals
Star-nosedmole
Mink
Muslaat (S)
Blackbear (N)
Snowshoehare (N)
Bobcat(N)
River otter
Frogs and reptiles
Wood frog
Spottedsalamander
Wood turtle (N)
Northem water snake
Insects and butterflies
Brown-eyedbutterfly
BOGS
PIants
Cotton grasssedge
Bog rosemary
Cranberryr
Pitcher plant
'Labrador
tea
Leatherleaf
Sundew
Sphagnummoss
Tamarack
Black spruce
Birds
Song sparrow
Common yellowthroat
White-throated sparrow
Hermit thrush
Nashville waribler
Mammals
Black bear
Bog lemming
Rep,tiles and amphibians
Redbelly snake
Insects and butterfies
Sulfur butterfly
Bog fritillary
FENS
Plants
Watercress
Shrubby cinquefoil
Swamp thistle
Ohio goldenrod
White lady's slipper
Beakedspike rush
Bladderwort
Birds..Common snipe
Yellow warbler
Common yellowthroat
Swamp sparrow
Red-winged blackbird
Mammals
Eastem cottontail rabbit
Raccoon
Frogs and reptiles
Snail
Blanding's turtle
Pickerel frog
Butler's garter snake
Common water snake
Insects and bufterf,ies
Baltimore checker-spotbutterfly
Mulberry-wing skipper butterfly
Viceroy butter0y
Purple and red-bodied damselflies
Theatment
Plants
Summary
Goingup?
Demonstratethe uptake of
pollutants into plant tissues.
Objectives
Students will:
. describe how plants remove
pollutants from the water.
"Treatment
Plants" in
fFrom
Discover Wetlands, p. 7L.I
Grade Level
2-12
Subiect Areas
Biology, Environmental
Science
hrration
Setup a day ahead;30
minutes for demonstration
and discussion
SeUtulg
Classroom
Skills
Gathering and interpreting
infornration
ChanhS the Cource
Compare this activity with
"MarshMystery," which
studies pollution intake by
animals.
Vocabuhry
pollutant, capillary action,
toxin
. analyze the limitations of this
ability when wetlands are
overloaded with pollutants from
the surrounding land.
Materials
.
freshcelerystalks,with leaaes
. 2 beakers
or jars
. redor blue
foodcoloring
. u)ater
. paring knife
MakingGonnections
Wetlands also provide a flood
control benefit. The wetland zone
along the edge of a stream, river,
or pond can temporarily capfure
and hold floodwaters. The excess
water is released gradually from
wetlands and the destructive
effects of sudden storm surges are
avoided. Similarly, when a heavy
load of pollutants enters a wetland, the wetland can hold the
pollutants for a while and release
them into nearby bodies of water
slowly. This often minimizes or
prevents the harmful effects that
would result if most of the
pollutants entered the water
within a short period of time.
Many people do not realize that
plants are vital to the health of our
water supply. In fact, wetlands
and their plants are an increasingly popular alternative for
The soils and plants in a wetland
filtering wastewater from homes,
can capture and hold, maybe even
schools,factories,and businesses.
use and change, many poilutants.
This activity helps students
Becauseof the relatively slow
appreciate wetland plants' natural
movement of water through a
ability to help keep our water
healthy wetland, plants form a
supply clean.
Background
Healthy wetlands perform some
very important functions in the
cleansingof polluted runoff and
wastewater. Pollutants include
petroleum products, heary
metals,pesticides,industrial
wastes,excessnutrients (suchas
nitrogen and phosphorus) from
householdor commercialuse,and
even litter. The soil layer and the
tangleof stems,leaves,and roots
in a denselyvegetatedwetland
impede the flow of water and act
r20
as a natural sieve. As a result, the
water that is processed by a
wetland usually enters an open
body of water in a much cleaner
state. Not surprisingly, a growing
number of communities around
the world are using wetlands as
part of a comprehensive wastewater treatment program.
barrier that allows many sediments and suspended pollutants
to settle down to the soil level.
Larger floating materials, such
as litter, often get caught in the
vegetation as well. All these
pollutants are buried as new soil
materials settle over them. Soil
particles often bind with pollutants and prevent them from
moving into an open body of
water, thus protecting the quality
of water. In some cases,the
microbiological activity in the soil
can actually render pollutants
harmless.
O TheWatercourse
andEnvironmental
Concern
Inc.1995
TreatmentPlants
Wetland plants play other roles in
the preservation of water quality.
During plant metabolism, plants
draw water, air, and nutrients
through their root system. In the
daytime, plants use carbon
dioxide and produce oxygen
during photosynthesis. At night,
plants produce carbon dioxide
during respiration. Much of this
gas exchange occurs through
pores (stomata) on the plant
surface. These pores also allow
water to escape to the atmosphere
as vapor (transpiration); some
minerals are excreted during
this process.
As plants draw water into their
roots they also take in nutrients
for metabolic activities. Wetland
plants can metabolize excess
nutrients from human activity,
thus protecting the open water
bodies that receive wetland
runoff. The cattail is a prime
example of a wetland plant that
will readily use these available
nutrients. Of course, there are
limits to what a wetland can do,
and it is possible to so overload
a wetland with nutrients that
eutrophication results.
TheActivity
Nofe:Prepare steps one and three
one day prior to the lessonRepeat thesesteps in front of the
classto show how the demonstration was prepared.
1. Add severaldrops of food
coloring to a water-filled beaker
or jar. In class,explain that the
food coloring represents pollution by a toxic substancesuch as
a pesticide. Let students suggest
other toxic substances.
2. Ask the students to imagine
that the water is flowing through
a wetland and the celery stalks
are the many plants (cattails,
sedges,grasses/etc.) growing
there .
3. Cut off the bottom half-inch of
the celery stalks and place the
stalks in the water overnight.
Over time, the colored water will
travel via capillary action up the
stalks, showing how plants can
absorb pollutants with the water
they "drink." The colored water
may or may not be visible on the
outside of the stalk. Cut off 1inch piecesof the celeqyand
hand them out for studentsto
Plants also take up toxic materials
when they draw water from their
environment. Toxins are stored
until the plants excrete them or
die. The toxins are then rereleased
into the water and soils of the
wetland, where they may be
captured by other plants, or bind
with soil particles. Even so, some
pollutant materials do find their
way through the wetland and into
our rivers, streams, and ponds.
Procedure
Warm Up
study closely. They will see
colored dots on the cut surface.
Explain that these are vertical,
water-filled channels in the
celery seen in crosssection.
4. Discuss what happens to
pollutants when they pass
through a wetland.
Wrap Up
Ask students:
How do wetland plants help
purify water?
Why is the water remaining in the
beaker still polluted?
Where does the water go after
uptake into the plant?
What happens to the pollutants?
Why can't we dump all of our
waste into wetlands?
Assessment
Have students interpret the role
plants play in water purification.
Extensions
Nature inYour
Neighborhood
Lots of pollutants run off of the
land from construction sites,
streets, highways, and the communities in which we live. Sometimes ditches or stormwater
management ponds are built io
filter polluted runoff and excess
rainwater from these sites. These
ponds are often planted with
wetland plants to aid in the
fiitering. As the runoff and
rainwater rest before flowing on,
many of the pollutants, especially
soil particles, settle to the bottom
and the cleaner water drains off
from the top.
Is there a stormwater management pond near where you live?
Find one in a safe spot, away from
speeding cars. If it is fenced off,
stay outside of the fence. Visit the
pond on a dry day and again just
Ask students what they think
happens when pollutants such as
toxic chemicals and garbage flow
through a wetland. Explain what
happens.
WOW!:The WondersOl Wetlands
t2l
after a heavy rain. Is there a
difference in the appearanceof
the water in the pond and,/or the
water y"*i"S into the pond?
Where is the water flowing from
and w_heredo you suppose it is
going? you may be a6te to see
water leaving the pond_is this
water cleaner?It should be!
This is how natural wetlands
_work.In fact, this ls a wetland_a
human-made one. If the pollutanl
load is managed with care the
pond will evolve into a beautiful
wetland for aII to enjoy! For
assrstancein finding a pond,
contact y-our highway depart_
ment
-office of public *oiks, o,
one of the groups listed on p.
330.
ilotes:
L22
@ TheWatercouneandEnvironmental
ConcernInc 1995
Wbtland
Metaphors
Summary
Background
Whatis a home,a sponge,and a
straineraII at thesametime?
Wetlands provide critical benefits
to plants, animals, humans, and
the total environment. (See
chapter 3.)
Consider a selectionof common
objectsas physical metaphors for
natural wetland functions.
Objectives
Students will:
"
I From Wetlanil Metaphbrs"
in Aquatic ProFct WILD,
WesternRegianalEnoiionmmtal EducntionCouncil, 1992.
'
Ad4ptedu,ith pennission.I '
Grade Level
1-12
Subiect Arcas
,
Environmental and Earth
Science
'
Duratlon
3G40 minutes
Settftrg
Classroom
Sldlls
Analyzing and interpreting
Gharting the Gour*
Try'MarshMysbry,"
'Treahrcnt
Plants," "Soak
"\iletland
It Up!,'
in a Pan "
and others for a more
detailed look at wetland
functions.
Vocahrhry
wetland functions, habitat,
filter
. describecharacteristicsof
wetlands.
. appreciatethe importance of
wetlands to wildlife and
humans.
. identify ecologicalfunctions
of wetlands.
Materials
. A Mystery MetaphorContainer
(e.g.,largepilloutcase,bag,or box)
thnt hasan openingjust large
utough to allow studentsto reach
insideto retrieaean obiectwithout
seeingthecontents
. sponge
. smallpillow
. soap
. eggbeateror mixer
. smalldoll cradleor picturesof
nurseryitems
. sieaeor strainer
. papercoffeefilter
. bottleof nntacidtablets
. smallboxof cerealor wild rice
. 3-inchx S-inchcardsuith magazinepicturesrepresentingother
wetlandfunctions(seechartat md
of actiuity)
MakingConnections
Citizens in our rapidly developing
world should understand the
benefits of wetlands as resources
for humans and other species. This
activity brings those benefits to life
and encourages a new appreciation of the many important roles
wetlands play.
WOll!: TheWondenOl Wetlan&
Most wetlands, with their abundance of food, vegetative cover
(shelter),and water, are rich with
diverse wildlife species.Coastal
and inland marshes,for example,
are the breeding, resting, and
wintering habitats for thousands
of migratory birds, including
ducks, geese/swans, shorebirds,
herons, and other wading birds.
Many species of fish and shellfish
that have important commercial
and recreationaluse reproduce
and spend part or all of their life
rycle in fertile wetlands. A wide
variety of reptiles, amphibians,
insects, and cnrstaceans also
breed and live in wetlands. Many
mammals depend on wetlands for
food, shelter, and water.
Wetland vegetation is highly
beneficial. Plants absorb nutrients
and help cycle them through the
food web. They keep water's
nutrient concentrationsfrom
reaching toxic levels. Plants
produce oxygen through photosynthesis,and they are an important food sourcefor other life
forms.
Wetlands have a unique ability to
purify the environment. They are
extremely effective natural
filtering systems.For instance,
they trap and neutralize sewage
waste, allow silt to settle, and
promote the decomposition of
many toxic substances.
Wetlands mitigate the harmful
effectsof sudden and seasonal
variations in the water supply.
When runoff from rain and spring
85
thau,is high, wetlandsretain
excesswater, allowing it to drain
into streams and rivers and
permeate the soil gradually.
Heaithy wetlands are buffer zones
that prevent flooding and erosion.
In drier periods, they hold
precious moisture long after open
bodies of water have disappeared.
As remarkable and resilient as
wetlands are, they do have limits.
Wetland functions can be compromised when portions are drained
and filied for other uses. When a
wetland is lost, the effects on
wildlife, humans, and overall
environmental qualitv can be
significant. Although many
wetlands are protected by federal
and state laws, there is still a need
to create a greater awareness of
the importance of wetlands as
unique and essential ecosystems.
Procedure
Warm Up
If necessary,provide the class
with background information on
the naturai functions of wetlands
and their value as wildlife habitat
(Seechapter 3.) Use "Wetland in
A Pan," p.212, if you need to give
a demonstration. Introduce
wetlands though posters,pictures, stories,etc. How do the
students feel about wetlands? Do
they think wetlands are important? Why? Discuss students'
answers and make a list of "pros/'
"cons"
and
on the board.
TheActiztity
l. Tell students that they are
going to expand the "pros" list
through the use ol metaphors.
Explain that a metaphor represents a thing or idea through
another thing or idea, such as in
"a tree
is a home," "the world is
a stage," or "books are windows
of thought." Ask students to
provide examples of other
metaphors. The household objects
86
in this activity are tangible
symbols of wetland benefits.
I Divide the class into groups of
four or five. Ask a representative
from each group to choose an
item from the Mystery Metaphor
Container. Each group must
decide how the object could
represent what a wetland is or
does. Ali items in the box have
something to do with wetlands.
3. Allow time for students to
discuss their answers in groups
before each group presents its
object and ideas to the class.
Examples are given in the chart
below, but students may come up
with other clever ideas.
Wrap Up and Action
As students report to the class,
discuss each idea and invite
others to add their ideas. Add to
the list of "pros" on the board. At
the end, ask the class to summarize the major roles that wetlands
perform. Have students' attitudes
and understanding changed since
they started the activity?
Sponge
:
Pillow or bed
Ees beater
Cradle
l, ,'
Strainer
' ,Coffee fiIter
'
Antacid
Cereaf rice,
piciure of garden
Soup
Picture of zoo
Picture of resort or
motel
Assessment
Have students:
. use metaphors to relate the
many functions of wetlands to
everydav objects.
. identrfy reasons wetiands are
important.
Extensions
Have students prepare displays
or short demonstrations on the
benefits of wetlands or prepare a
wetlands benefits bookiet, each
student contributing one page.
Besources
Mitsch,William J.,and J. G.
Gosselink.1993.Wetlands.
New
York: Van Nostrand Reinhold.
(No/cio 7'ettclrcr:Use
the chart
belor,r'tohelp prepareyour
Mystery Metaphor Container,
although metaphorsother than
thesemight be offered by students.)
Absorbs excesswater causedby runoff; retains moist
ture for afime evenif standing water dries up (spon$e
stays we!,9ven after it has absorbed a spill)
,,,
A resting place for migratory birds
andoxygen into the water
flxes-nutrimts
ftod9.F.3.T.yrsery that shelters,protects, and feedi
fdisuaui:
Strarls silt and debris from water (keepswater
zupplyclean)
F_ilterssmaller impurities from water (excessnutrients, toxins)
Neutralizes toxic substances
Providesnutrierrt-rich foods for wildlife and humans
. . '
Helps cleansethe environment
Habitat for diverse wildlife
Restingor wintering place for migraring waterfowl
le;The Watercourse
and EnvironmenlalConcernlnc. 1995
Wetland Weirdos
Student Page
CattailInvestigation
Collect some cattails to study. You
will find them growing in fresh or
slightly salty water along creeks,
rivers, ponds, lakes, and wet
roadsideditches.You will need
the whole plant: roots, if you can
get them, stalk, leaves,stem, and
the "cat's tail" at the top. Gather
one plant for every four to six
students-you will be able to
share plants to study, so do not
takeall of the cattailsgrowing
in one area!
1. Carefully examineall parts of the plant and how they are arranged.
On anothersheet,draw a picture of eachpart.
2. Pull off one of the leaves.Where are the leavesattachedto the stalk?
Are both sides of the leaf the same? Is the leaf flat or does it have some
thickness?Write your answersbelow.
3. Cut the leaf crosswise (see diagram) and look at the cut edge with a
magnifying lens. Wha/s inside cattail leaves that makes them hard to tear?
4. Cut a thin slice of the shoot and draw it on the back of this page. The
shoot is edible, so tastea piece!Describethe taste.What do you think
the white, spongy stuff inside is for?
CATSr*tu
5. The stem holds the cat's tail up. Cut the stem crosswise,then cut a
thin slice off the cut end. Observe the slice with a dissection scope.
Draw a picture of the slice'smiddle, or pith, on the back of this sheet.
6. What do you think the holesin the pith are for? (Hint:Wetland plants
grow in wet soil that has no oxygen,and plants' roots need oxygen.)
7. Carefully pull some of the fuzz from the cat's tail. Theseare ovaries
and fruits. Are they all the same? What differences can you see?(Use a
magnifying lens.)
clog
sec--ttorloF
s+loor
fu
eRoSS.SEC.rto$l
OF 6TGH
8. When ovaries are pollinated, they soon become fertilized seeds that
will grow new plants. Put some of the different fruits between layers of
wet paper towels and seal in a plastic bag that zips closed. Which of the
fruits start growing after a few weeks?
9. Why do you think cattails make so many fruits?
cPrrH)
-u^q|tFt6D-
y-v
10. How might cattail seeds be pollinated? How are seeds spread?
WOW!:TheWonders
Ol Wetlands
97