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Pages54-61inJ.C.Grégoire,A.M.Liebhold,F.M.Stephen,K.R.Day,andS.M.Salom,editors.1997.Proceedings:Integratingculturaltacticsintothemanagementofbarkbeetleandreforestationpests.USDAForestServiceGeneralTechnicalReportNE-236.Auser-friendlyPC-basedGISforforestentomology:anattempttocombineexistingsoftwareMARIUSGILBERTLaboratoiredeBiologieanimaleetcellulaire,CP160/12UniversitéLibredeBruxelles,50av.F.D.Roosevelt,1050Brussels,BelgiumABSTRACTWepresentacombinationofexistingsoftwarewhichshouldfacilitatetheuseofGISbyforestentomologists.TheuseofexistingGISbyecologistswhowanttotakeadvantageofthespatialcomponentoftheiranalysesisoftenhinderedbythedifficultyofuseandcostofsuchtools.Moreover,itmightbeusefultohaveasystemwhichcanbecarriedtoremotelocationswhereaccesstoamainframecomputerorpowerfulworkstationsisunavailable.Itisnowpossibletohaveagoodsystemrunningonasinglepersonalcomputerduetotheincreasingpowerandthelowcostofthistypeofhardware.Wehavegatheredprogramscharacterisedbytheirsimplicity,lowcost,andperformances.IDRISIisasimpleandinexpensiveGISwhichhasasimplefilestructurethatallowstheusertocreatehis/herownanalysisscriptswithbasicknowledgeincomputerscience.VARIOWINisageostatisticalpackagewhichperformsexploratoryvariographyand2Dmodelling.SURFERisasurfacemappingsystemabletocreateandtodisplaygridsusingseveralmethodsofspatialinterpolationsincludingtwodimensionalanisotropickriging.FRAGSTATSisaprogramwhichperformslandscapeanalysesandfinally,CORELDRAWisavector-orientedpackagethatcanbeusedforoutputofbothbitmapandvectoroutput.Theseprogramswerenotdesignedtoworktogetherandproblemsmayoccurduetotheheterogeneousnatureofthesystem.Conversionfiledifficultieswereencounteredandwewerefacedwiththecomplexityofusingdifferentprogramstoperformoneanalysissequence.Anadditionalmoduleisbeingdevelopedtosolvetheseproblemsandthewholesystemshouldbeabletomanagedata,analyzetheirspatialcomponentanddisplaymapoutputinasimpleanduser-friendlyway.KEYWORDS:GIS,Spatialanalysis,geostatistics,software.GEOGRAPHICALINFORMATIONSYSTEMS(GIS)arewidelyusedinenvironmentalmanagement(Burrough1993).Inecologyandparticularlyinforestentomologytheymaybeofconsiderableinterestforthestudyofspatialpatternandinsectspatialdistribution(Liebholdetal.1993,Coulsonetal.1993,Turner1989).Forexample,themeasurementofspatialdependenceisessentialinsamplingmethodology(Rossietal.1992,Legendre1993,Fortinetal.1989).Moreover,theinteractionbetweeninsectsandtheirenvironmentalwaysbearsaspatialcomponent(BorthandHubert1987,Hohnetal.1993).AGISisacomputerprogramdesignedtocollect,retrieve,transform,display,andanalyzespatialdata.GIScanincorporategeoreferenceddatatoproducemapsorlayers.Usually,amaplayerorathemeiscomposedofonlyonetypeofdata.GIShavetheabilitytoimportandmanagedatafromdifferentsources:mappeddata,alphanumericdata,remotelysenseddata.ThesetypesofdatamaythenbecombinedtobuildaGISdatabase.Usingthisdatabase,theusermaycreatemapoutputsordisplayviewsrelativetospecificquestions.Thesesystemshaverecentlyimprovedtheirabilitiestocarryoutspatialanalysesintegratingnewbuilt-infunctions(spatialinterpolation,spatialautocorrelation,overlayanalysis,etc.).Furthermore,theusermaycreatehisownanalysisfunctionswithpersonalscripts.GILBERT55NewGISusersoftenmustchoosebetweentheperformancesoftheirsystemandthetimethattheywillspendtobeabletouseit.Simplesystemsareeasytolearn,butoftenlackintegratedfunctionswhichobligestheusertowritehis/herownscripttoachievespecificgoals.Powerfulsystemsarecreatedforadiversityofpurposes.Theybearusefulbuilt-infunctions,butusersmustbecomefamiliarwiththewholeGISenvironmenttousethemproperly.Thesepowerfulsystemsusuallyrunonworkstations.Thistypeofhardwareandassociatedsoftwareareexpensiveanddemandknowledgeofanewoperatingsystemenvironment.Forexample,theuseofanimportantapplicationsoftwaresuchARC/INFOdemandsknowledgeintheUNIXoperatingsystem,knowledgeoftheARC/INFOfilestructureandtopology,oftheARC/INFOhighnumberofcommandsandoftheAML(ArcMacroLanguage).However,userswhojustwanttotakeadvantageofthespatialcomponentoftheirdatahavedifferenthardwareandsoftwarerequirementsthanuserswhoareplanningcompleteGISresearchprojectsinvolvingextensivedatacensus.Thefirstkindofuserscannotaffordexpensivesystemstoaddaspatialanalysiscomponenttotheirecologicalstudies.ThisiswhyaninexpensivesystemworkingonasinglePCmightinterestsuchusers.Moreover,theincreasingpowerofPCsmakesGISmoreandmoreefficientonthishardware.Finally,asystemrunningonasinglePCmightbeusefulonthefieldortoremotelocationswhereaccesstomainframecomputerorpowerfulworkstationsisunavailable(Carveretal.1995).Wepresentacombinationofinexpensiveanduser-friendlyPC-basedsoftwarewhichshouldhelppotentialuserstointegratespatialcomponentstotheirecologicalstudies.SystemPresentationFirst,informationaboutexistingsoftwarewascollected,mostlyontheInternetinWebpages.Additionally,userdiscussionsavailableinnewsgroupsrelatedtoeachsoftwarewerefollowed.ThesoftwareapplicationsweretestedonaPentium90MHzPCwith8MbytesofRAM,undertheWINDOWS95operatingsystem.ARC/INFOPC,MAPINFOandIDRISIhavebeentestedforGISfunctionality.VARIO