Lesson Plan for Santa Rita Experimental Range Vegetation...

LessonPlanforSantaRitaExperimentalRangeVegetationMonitoringMarthaGebhardt,OutreachCoordinator

Objectives:Part1:StudentswilllearnaboutcommonplantspeciesonSRERthroughvegetationmonitoringtechniquesusingthebelttransectmethod.StudentswillanalyzeandpresentdatacollectedinPart1byclassifyingplantspeciesbasedongrowthhabits(grasses,forbs,shrubs)Part2:UsetheScientificMethodto:

MakepredictionsaboutplantspeciesatdifferentlocationsontherangeAnalyzeplantspeciesovertimeusingpastdatarecordsandphotographsofthetransectsComparevegetationtrendstoprecipitationandgrazinghistoryCompare/Contrastresultstootherlocationsontherange

Part1:MaterialsClipboard,penorpencil,andpaperforrecordingdataMeasuringtapethatisatleast100ftlong1ftrulerSurveyflags(apx.10)SRERplantguideAdditionalplantguide(s)[optional]BackgroundTherewillbealocationpredesignatedonSRERwherestudentscangotakevegetationmeasurementswithoutdisturbingotherscienceexperimentsthatareongoing.Explainthatsince1972,everythreeyearsplantdensitymeasurementshavebeenrecordedonSRER.Today,wewillrecordthisdatausingthesameproceduresscientistsuse.Wewillbeusingabelttransectmethod.Wewillmeasureout100ft.withmeasuringtape.Plantdensitythatiswithin1ftofthemeasuringtapewillberecorded.Counteachplantspeciesonlyonce.BeltTransectImage:

Procedure1.Separateclassinto3-4groupsdependingonsizeofclass.Usuallyabout4-5students/groupensureseveryonewillhavetasksthroughoutthelesson.2.Markastartinglocationforeachgroup.Makesuregroupsdon’tendupoverlappingeachotherwhentheymeasureouttheirtransects.Trytouseavarietyoflocations---havegroupsgooffindifferentdirections,ifthere’sanelevationchangehavesomegroupssurveyalongitandothersnot,aimforavarietyofvegetation,ifpossible.

3.Haveeachgroupmeasureout100ft.andmarktheendinglocationwithasurveyflag.4.Havestudentsrecordimportantinformationabouttheirtransect.Someusefulinformationthatmightaffectvegetationincludes:pastweather(ifknown),locationoftransect,orevidenceofpredators(scat,fur,etc.)5.Countallplantspecieswithinthetransectusingtheplantspeciesguide.Don’tworrytoomuchaboutmakingsureyouhavetherightspeciesifit’shardtotell.Differentgrassspeciescanbedifficulttodistinguish.Itismoreimportanttocounttheindividualthanitistoaccuratelyidentifyit.ExampleDatasheet:

note—thisisahypotheticaldatasheetforpurposesofprovidinganexample6.Sumandcategorizetheplantsineachtransectaseither:grasses,forbs,orshrubsDefinitionsofGrasses,Forbs,andShrubs:Grasses-vegetationconsistingoftypicallyshortplantswithlongnarrowleaves,growingwildorcultivatedonlawnsandpastureForbs-vascular(havingtissuethatconductwater,sap,andnutrients)plantswithoutsignificantwoodytissueabovetheground.

Shrubs-perennial(plantthatlivesmorethan2years),multi-stemmedwoodyplantthatisusuallylessthan4-5metersinheight.Shrubstypicallyhaveseveralstemsarisingfromorneartheground.(cactusandchollaareshrubs)ExampleDatasheet:

note—thisisahypotheticaldatasheetforpurposesofprovidinganexample7.Presentandcomparegroupresults.Questionstoconsider:-Whydoyouthinkyourgroupgothigh/lownumbersofgrasses,forbs,orshrubs?-Whydidothergroupsgethigher/lowernumbersofgrasses,forbs,orshrubs?-Whichgrouphadthegreatestoveralldiversityofplantspecies?-Whichgrouphadtheleastoveralldiversityofplantspecies?-Whichgrouphadthehighestdensityordiversityofgrass,forb,and/orshrubspecies?Why?-Whichgrouphadthelowestdensityordiversityofgrass,forb,and/orshrubspecies?Why?

Part2:Materials

PenorpencilpaperSRERplantguideAdditionalplantguide(s)[optional]Datasets—4totalGraphingpaperorcomputerwithexcelCalculatorBackgroundVegetationtransectshavebeenongoingat132sitesonSRERsince1972(greenpointsonmap).Densitywasmeasuredevery3yearsbetween1972-1984and1991-2015.Today,wewillanalyzethedatacollectedat4ofthesesites(yellowstarsonmap).Oneofthesesiteshadafirein1994(siteontheeast).Wewillanalyzethenumberofgrasses,forbs,andshrubsateachofthesites.Wewillanalyzetrendsinvegetationandmakeinferencesaboutwhetherornotthesetrendscanbeexplainedbypastprecipitationorcattlegrazingrecords.Wewillcomparevegetationacrossthesitesandseetheeffectsfirehadonvegetation.MapofvegetationtransectsatSRER:

Site Location Elevation(m)

Site1

Site2

Site3

Site4

Procedure1.Separateclassinto4groupsandgiveeachgroupadataset.

Notesondatasets:Eachdatasetcontains:plantdensitydata,planttransectphotos,precipitationdata,andcattlegrazingdata

PlantDensityData-Thisisthetotalnumberofeachplantspeciesoccurringinthebelttransectperformedateachsite.-“xxx”valuesmeannodataisavailablebecauseareadingwasnotmade.Assumeallofthesevaluesequal0whenanalyzingdata.

PlantTransectPhotos-Theseareallavailablephotosoftheplanttransects.Someofthephotodatesmightnotalignwithsampledates,butyoushouldstillbeabletovisualizedifferencesinvegetationovertime.

PrecipitationData-Thesereadingaretakenfromtheraingaugelocatednearesttoyoursite(seeimagebelow)

CattleGrazingData-Asweknow,manyresearchersatSRERarestudyingcattlegrazing.Thisdataisthetotalnumberofcowspresentinthesiteforeachyear.MapofraingaugesatSRER:

1 Pasture8Transect14 12692 Pasture12BTransect7W 9813 Pasture5NTransect11W 8834 Pasture6ATransect1 1284

SWraingauge

NWraingauge

RUELAraingauge

FORESraingauge

2.Formahypothesesabouttheplantdensitydatausingif,then,becausestatements.Forexample,ifthereismorecowsinthesiteforacertainyear,thentherewillbelessgrassdensity,becausecowseatgrass.Asagroupdevelop2hypotheses:1foryoursiteand1acrosssitesThingstoconsider:findingsfromPart1,elevationateachsite,Whateffectdoyouthinkcattlegrazingorprecipitationwillhaveonvegetation?WhatdoyouknowaboutthevegetationhistoryofSRER?Howwillfireaffectvegetation?3.Analyzethedataforyoursite-Classifyeachplantspeciesasgrass,forb,orshrubusingthedefinitionsprovidedinPart1andtheSRERplantspeciesguide.-Sumthetotalnumberofgrasses,forbs,andshrubsforeachyear.-Ifpossible,graphthesevaluesovertime-Lookatdiversity:Bothwithineachoftheseclassificationsandtheoverallplantdiversityatthesite-Arethereanysurprises?-Howdidthevegetationchangeovertime?-Compareresultstotheplanttransectphotos.Canyouseehowtheresultscomparetoactualphotographs?-Compareresultstothecattlegrazingandprecipitationdata.Aretheresimilaritiesordifferences?Forexample,dohigherlevelsofcowsaffectvegetation?Doesmoreorlessrainforaspecifictimehaveaneffectonvegetationtrends?4.Re-visitthehypothesisforyoursite-Doyourresultssupportorrejectyourinitialhypothesis?-Haveyoulearnedmoreinformationthatmighthelpexplainwhytheresultssupport(orreject)yourhypothesis.Forexample,didtheprecipitationandcattlegrazingdatahelpyouexplainthevegetationdensitydata?-Areyouconvincedbytheresults?Doyouneedmoreinformationtosaywhetherornotyourhypothesiswassupportedorrejected?(ThinkaboutPart1:Howsimilarordifferentwaseachgroup’sresults?)-Whataresomeadditionalquestionsthathavearisenthroughthisanalysis?-Doyouhaveideasforfuturequestionsorresearch?4.Shareresults.Haveeachgrouppresenttheirinitialhypothesis,vegetationdensitydataovertime,andtheirconclusions(#4).Remindstudentstoconsidertheir“acrosssites”hypotheses.Aseachgrouppresents,encouragestudentstoaskquestionsthatwillhelpthemdecideiftheir“acrosssites”hypothesisissupportedorrejected.Forexample,ifGroupAdevelopedan“acrosssites”hypothesisthatinvolvedcattlegrazingandthegrouppresenting(GroupB)didnotincludethisdata,GroupAshouldaskGroupBwhattheircattlegrazingdatawasandhowitcomparedtotheirvegetationdensitydata.5.Getbackintogroupsandgivestudents5minutestodecideiftheir“acrosssites”hypothesiswassupportedorrejectsbytheinformationtheyheard.Re-visitthepointsin#4.6.Haveeachgroupsharetheirfinalconclusions.Wastheir“acrosssites”hypothesissupportedornotandwhy?