Sun

Leaves AlgaeMicrobes

(fungi, bacteria)

Smaller leaf particles

Shredders(crane flies, some caddisflies and stoneflies, sowbugs, and scuds)

Collectors/ Gatherers(black flies, net -spinning caddisflies, mayflies, midges)

Predators(Dobson flies, dragonflies/ ”hellgrammites ”)

Grazers/ Scrapers(caddisflies, water pennies,

midges, and mayflies)

Name:____________________________ Date:_______________________

StreamEcologyandMacroinvertebrateBiologyNotesOutline

BackgroundInformationforDevelopingyourResearchProject

Ecology

• Definition:Thestudyofinteractionsbetweenindividualsandindividualsandtheirenvironment

• SimplifiedFoodChains:

– PlantsHerbivoresPredators

– DeadorganicmatterDetritivoresPredators

• Muchgreenmaterialintemporalareasisnoteatenbyherbivores,butisdeliveredtothedetritalpool

• DetritusDead,decaying,particulateorganicmatter

FunctionalFeedingGroupsofMacroinvertebrates

• Shredders

– Consumecoarseorganicmatter,suchasleaves(Sowbugs)

• Collectors

– Consumefinepiecesoforganicmatter,suchasleaffragmentsorothermaterialonstreambottom

– FilteringCollectors(Clams)

– GatheringCollectors(Caddisflylarvae)

• Scrapers

– Feedonattachedperiphytonlocatedonsubmergedunderwatersurfaces(Example:Snails)

• Predators

– Feedonotherinvertebrates(Example:Dragonflies)

Foodprocessing…ofthisdetritusisamajorecosystemfunction

• Soilformation

• Supportspredators

– (somepredatorsconsumedbyhumans)

• Processedinstreams

– Ifitaccumulated,wouldcreateanoxicconditions

• Influenceofprocessingrates:

– Qualityofdetritus(P,N,polyphenols,lignins,etc)

– Fungiandbacteriacolonization

– Invertebratefeeding

EcologicalInteractions

• Microbesandinvertebratesprocessandgetenergyfromdetritus

– Microbesoftenoverlookedbystudents/teachersonmanylevels

• Differentspeciesprocessmaterialsatdifferentrates

– Ifaspeciesislost,theentireecosystemfunctionwillchange

– Speciesarebeinglostatanalarmingrate

Adaptations

Variationsofanatomy/structureallowfortolerance,feedingcapacities,andcompetition

Importance

• ImpactsonHumansExample:

– Aug.17,1988,an85footsectionofRt.675BridgecollapsedoverthePokomoke(EasternShore)

– Reductionincrosssectionareaofpiles18‐35%

• Dueto:Bacteriaandfungaldecay,Caddisflydecay,watercurrents

– In1977,MDEestimatedCaddisfliesoccupied30‐100%oftheunderwaterpilesurfaces

– From1976‐1986,Caddisfliesper1.5sqfeetintheareaaveraged543.5

• (High1977=1837;Low1986=50)

– Since1977,3underwaterinspections,pilemeasurementswereinconsistent

– Ifuse“ChemicallyTreatedWood,”lessfungalandbacterialgrowth,therefore,less

caddisflies

TrichopteraBiology

• Taxonomy:

– PhylumArthropoda

– ClassInsecta

– OrderTrichoptera

– FamilyLepidostomatidae

– GenusLepidostoma

• Larvaefeedondetritus(shredders)

• Protectivecases

• YouwillidentifythesetoOrderatthestream,andtoFamilyinthelab

AmphipodaBiology

• Scuds;Detritivores(Shredders)

• Taxonomy:

– PhyllumArthopoda

– ClassMalacostraca

– SuperorderPeracarida

– OrderAmphipoda

– FamilyGammaridae

TrichopertaLifeCycles

CompleteMetamorphosis:

AmphipodaLifeCycle

IncompleteMetamorphosis:

Tolerance/SensitivityofMacroinvertebrates

• Macroinvertebratescanalsobecategorizedbytheirleveloftoleranceorsensitivitytostreamconditions

– Dissolvedoxygen

– Nutrients

– Pollutants

– Chemicalquality

• Somespeciescanlivein“lower”qualitywater,andaresaidtobe:

– Moretolerant

– Lesssensitive

ShreddersRoles

• Ecological/Trophic

– Leaflitterbreakdown

• CPOMFPOM

– CourseParticulateOrganicMatter

– FineParticulateOrganicMatter

• HumanImpact

– Predators(Trout,etc)

– Bio‐indicatorexample

• 0‐3.75=NoImpairmentEvident

• 3.75‐6.50=ModerateImpairment

• >6.5=SevereImpairment

StreamWaterChemistry

• pH

• Temperature

• Nitrates

• Phosphates

• Chloride

• DissolvedOxygen

Watershed

Definition:theareaoflandthatdrainstoa

particularpointalongastream

Eachstreamhasitsownwatershed

Topographyisthekeyelementaffectingthisareaofland

Theboundaryofawatershedisdefinedbythehighestelevationssurroundingthestream

Highlevelsofpavedsurfaces,orimperviouscover,andlandusechangescanhavemanyimpactsonawatershed

HarmfulPollutantsinRunoff

• Bacteria

• Nutrients

• Pesticides

• OilandGrease

• Turbid(muddy)water

• HeavyMetals(zinc,lead,copper)

• Runoffincreaseswithanincreaseinimpervioussurfaces

RiparianZone

• Definition:Theinterfacebetweenlandandastream

• Riparianvegetationisoftenplantedaspartofstreamrestorationeffortsbecauseitcan:

– Removenutrientsfromrunoff(fromfertilizers,etc)

– Biofilterpollutants

– Trapsediment(lessturbidwater,improvestreambanks)

– Improvewildlifehabitat

– Shadewater,mitigatingwatertemperaturechanges

– Reducesoilerosion,reduceflooddamage

Whatisthebestwaytoevaluatestreamhealth?

• Waterchemistryismoretransientthanbioticindexofmacroinvertebratesdueto:

– Point‐sourcepollution

– Rainevents

– Seasonalroadsalting

– Inconsistentlittering/dumping

PhysicalRegionsofaStream(HabitatTypes)

Riffle:Rapidlymovingwater,turbulent

Pool:Deep,slowlymovingwater

Run:Smoothflowingwater,mediumwaterspeed

Howdoyouthinkthesedifferenthabitattypeswilleffectwaterchemistryandmacroinvertebratepopulations?

YourResearchProject

Objectiveistoutilizealearnedunderstandingofstreamecologyandmacroinvertebratebiologyto

investigatetheeffectsofhabitatpreference,possiblyduetoavailablenutrientsanddissolvedoxygen,onmacroinvertebratespeciesdiversityandabundanceinHerefordHighSchool’sstream

Howcanwedothis??