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1、Team#14749page29of29SummaryManyscholarsconcludethatleafshapeishighlyrelatedwiththeveins.Basedonthistheory,weassumetheleafgrowthineachdirectionsatisfiesafunctionFα.Fortheleavesinthesametree,theparametersaredifferent;forthoseofseparatetrees,thefunctionmodeisdifferent.Thustheshapeofl
2、eafdiffersfromthatofanother.Intheendofsection3,wesimulateonegrowingperiodanddepicttheleafshape.Throughthousandsofyearsofevolution,theleavesfindvariouswaystomakeafulluseofnaturalresources,includingminimizingoverlappingindividualshadows.Inordertofindthemainfactorspromotingtheevoluti
3、onofleaves,weanalyzethedistributionofadjacentleavesandtheequilibriumpointofphotosynthesisandrespiration.Besides,wealsomakeacoronaryhierarchicalmodelandtransmissionmodelofthesolarradiationtoanalyzetheinfluenceofthebranches.Astothetreestructureandtheleafshape,firstweconsideronespeci
4、es.Differenttreeshapeshavedifferentspacewhichisbuiltupbythebranchqualityandangle,effectlightdistribution,ventilationandhumidityandconcentrationofCO2inthetreecrown.Thesearethefactorswhichaffecttheleafshapeaccordingtothemodelinsection1.Hereweanalyzethreetypicaltreeshapes:Smallcanopy
5、shape,OpencentershapeandFreedomspindleshape,whichcanbedescribedbyBPnetworkandfractionaldimensionmodel.Wefindthatthefactorsmainlyaffectthefunctionofthataffectstheadditionalleafarea.Factorsareassembledindifferentwaystocreatedifferentleafshapes.Sothattherelationshipbetweenleafshapean
6、dtreeprofile/branchingstructureisproved.Finallywedevelopamodeltocalculatetheleafmassfromthebasicformulaofm=ρ∙V.Byadjustingthecrownofatreetoahalfellipsoid,wefirstdefinethefunctionofrelatedfactors,suchastheleafdensityandtheeffectiveratioofleafarea.Thenwedevelopthemodelusingcalculus.
7、Withthismodel,weapproximatelyevaluatetheleafmassofamiddle-sizedtreeis141kg.Team#14749page29of29Deareditor,Howmuchtheleavesonatreeweighisthefocusofdiscussionallthetime.Ourteamstudyonthethemefollowingthecurrenttrendandwefindsomethinginterestingintheprocess.Thetreeitselfiscomponentby
8、manymajorelements.Inourfindings,w
