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1、ForestEcologyandManagement155(2002)163170MaximumsizedensityrelationshipsformixedsoftwoodsinthenortheasternUSAa,1b,*DaleS.Solomon,LianjunZhangaUSDAForestService,271MastRoad,Durham,NH03824,USAbCollegeofEnvironmentalScienceandForestry,StateUniversityofNewYork,OneForestryDrive,Syracuse,NY13
2、210,USAAbstractThemaximumsizedensityrelationshipsorself-thinninglinesweredevelopedforthreemixed-softwoodclimaxforesthabitats(hemlock-redspruce,spruce-fir,andcedar-blackspruce)inthenortheasternUSA.Theplotdatawerecollectedfromanextensivedatabaseusedingrowthstudiesfrom1950to1970,andrepresen
3、tedawiderangeofspeciescompositions,sites,managementoptions,anddensities.Plotshavinglatesuccessionalspeciescompositionswithrelativedensityindexhigherthan0.7wereselectedasthemostfully-stockedplotsformodeldevelopment.Reducedmajoraxisregressionwasusedtofittheself-thinninglinestothedata.Thedi
4、fferencesbetweenthethreeforesthabitatsweretestedusingthe95%confidenceintervalsofthecoefficientsoftheself-thinninglines.Theresultsindicatedthattherewerenodifferencesbetweenthehemlock-redspruceandspruce-firhabitatsforbothrelationshipsofthemeantreevolumeversusnumberoftrees,andthequadraticmean
5、treediameterversusnumberoftrees.Thus,thesetwohabitatswerecombinedtodevelopasingleself-thinningline.However,thecedar-blackspruceforesthabitatrequiredaseparateself-thinningline.Thesemaximumsizedensityrelationshipscanbereadilyusedtoconstructstanddensitymanagementdiagrams.#2002ElsevierScien
6、ceB.V.Allrightsreserved.Keywords:Self-thinning;Standdensity;Stocking;Mixed-softwoodforest;Northeast1.Introductionquadraticmeandiameter)overtime.Essentially,thesetoolsaresimplestandaveragemodelsthatgraphicallyStockingchartsandstanddensitymanagementcharacterizegrowth,densityandmortalityat
7、variousdiagrams(DMDs)areusefultoolsforpracticingstagesofstanddevelopment.Forestmanagerscanuseforesters.Theyprovidevaluableinformationandthemtoassessstandconditionsbasedonfieldsurveys,guidelinesonsilviculturaltreatments(e.g.thinning)andtorapidlydesignandevaluatealternativedensity
