Regionalassessmentofwetlandplantcommunitiesusingth

RegionalassessmentofwetlandplantcommunitiesusingtheindexofplantcommunityintegrityChristinaL.M.Hargissa,*,EdwardS.DeKeysera,DonaldR.Kirbya,MichaelJ.EllbaDepartmentofAnimalandRangeSciences,NorthDakotaStateUniversity,HultzHall,Fargo,ND58105,USAbNorthDakotaDepartmentofHealth,DivisionofWaterQuality,918EastDivideAvenue,4thFloor,Bismarck,ND58501,USA1.IntroductionDeKeyseretal.(2003)developedavegetativeIBIforseasonalwetlandsinthePrairiePotholeRegion(PPR)thatwastermedtheIndexofPlantCommunityIntegrity(IPCI).WetlandassessmentusingtheIPCIwasbasedondisturbancelevelandmultiplevegetativecompositionmeasurements.ThefocusoftheirresearchwastheMissouriCoteausub-ecoregionoftheNorthwesternGlaciatedPlains(NWGP)EcoregionlocatedinthemixedgrassprairieofNorthDakota.TheIPCIwasfoundusefulinassessingtheconditionofseasonalwetlandplantcommunitiesintheNWGPofthePPR(DeKeyseretal.,2003).However,itsapplicabilitytootherecoregionsandwetlandclassesofthePPRanditsreliabilityasanassessmenttoolgivenmajorclimaticdisturbancessuchasdroughtswereinquestion.Thecurrentstudywasdesignedtoanswerthesequestions.InthisstudytheseasonalwetlandIPCIdevelopedbyDeKeyseretal.(2003)wasevaluatedoverawiderecologicalindicators8(2008)303–307articleinfoArticlehistory:Received20December2006Receivedinrevisedform28February2007Accepted1March2007Keywords:WetlandsWetlandvegetationMetricPrairiePotholeRegionIPCIIBIabstractTheIndexofPlantCommunityIntegrity(IPCI)wasdevelopedtoassesswetlandplantcommunitiesinthePrairiePotholeRegion.TheIPCIevaluatestheconditionofwetlandplantcommunitiesbasedondisturbancelevelandmultiplecommunityattributes.How-ever,theindexwasdevelopedforseasonalwetlandsfromlimitedspatialandtemporaldata.Wetestedtheindexforseasonalwetlandsanddevelopedanindexfortemporaryandsemi-permanentwetlandsbyevaluatingvegetativecompositionofwetlandsthroughouttheNorthernGlaciatedPlainsandNorthwesternGlaciatedPlainsEcoregionsofSouthDakota,NorthDakota,andMontana.In2003and2004,weselectedwetlandsbasedonclassificationandtypeofdisturbance,rangingfromlittledisturbance(nativerangeland)toheavilydisturbed(cropland).WeanalyzedthedatausingtheIPCIvegetationmetricsdevelopedforseasonalwetlands,andfurtheranalyzedusingnonmetricmultidimensionalscalingandclusteranalyses.Allvegetationmetricstestedweresignificantinindicatingdisturbancelevel.Basedondataanalysis,fivebiologicallysignificantgroupsrelatedtointensityofdisturbance(Verygood,Good,Fair,Poor,andVerypoor)weredeterminedforseasonalwetlands,andthreeconditionclasses(Good,Fair,andPoor)fortemporaryandsemi-permanentwetlands.Scorerangeswereassignedtothemetricsaccordingtothedeter-minedclasses.UsingtheIPCImethod,wetlandsthroughouttheNorthernandNorthwesternGlaciatedPlainsofSouthDakota,NorthDakota,andMontanamaybeplacedintodistur-banceclasses.Thisdatacanthenbeusedforecologicalpurposesandmitigationneedssuchasmonitoringtrendsonreclaimedorrestoredwetlands,regionalinventories,andforevaluationofecologicalfunctions.#2007ElsevierLtd.Allrightsreserved.*Correspondingauthor.Tel.:[phone];fax:[phone]E-mailaddress:[e-mail](ChristinaL.M.Hargiss).availableat–seefrontmatter#2007ElsevierLtd.Allrightsreserved.doi:10.1016/j.ecolind.2007.03.003geographicareaincludingothersub-ecoregionsofNWGPandNorthernGlaciatedPlains(NGP)ofthePPR,aswellasawiderrangeofanthropogenicandnaturaldisturbances.AnIPCIfortemporaryandsemi-permanentwetlandswasalsodevelopedforthesamegeographicareaandrangeofdisturbances.2.Materialsandmethods2.1.StudyareaTheNGPecoregionisinthetransitionzonebetweentheeasterntallgrassprairieandthewesternmixedgrassprairie(BarkerandWhitman,1988),andiscomposedofglacialdriftwithflattorollingtopography(Bryceetal.,1998).TheNWGPecoregionisinthewesternmixedgrassprairie(BarkerandWhitman,1988)andmarksthemostwesternedgeofcontinentalglaciation(Bryceetal.,1998).Thedominantlandusesinthesub-ecoregionssampledoftheNGPandtheNWGPissmallgrainandlivestockagriculture(Bryceetal.,1998).Prominentstressorsincludegrazing,haying(mowing),burn-ing,cropping,andsedimentation;whichincludecultivation,thepossibilityforexcessivenutrientloadsandanoxia,andpesticideandheavymetalcontamination(WalkerandCoup-land,1970;Kantrudetal.,1989;Adamus,1996).Temporary,seasonal,andsemi-permanentwetlandswerestudied(Stew-artandKantrud,1971).Temporaryandseasonalwetlandsaretypicallysmallareaslessthan2hainsize.Semi-permanentwetlandsarelargerandtendtobeatleast2haormoreinsize.Thecurrentstudywasconductedin2003and2004on36temporary,39seasonal,and35semi-permanentwetlandswithinNorthDakota,SouthDakota,andMontana.WetlandsassessedinthesouthernpartofSouthDakotawereexperiencingdroughtconditionswhilewetlandsinthenorthernpartofSouthDakota,NorthDakota,andMontanawerereceivingaveragetoabove-averageprecipitation.Datafromthecurrentstudywascombinedwithdatafrom27temporary,46seasonal,and32semi-permanentwetlandsassessedbyDeKeyser(2000),DeKeyseretal.(2003),andKirbyandDeKeyser(2003).ThisdatasetwascollectedinNorthDakotaunderaveragetoabove-averageprecipitation.2.2.Samplin