简介：PiceamongolicaisanendemicandendangeredspeciesinChina.EcosystemmadeofPiceamongolicaisaspecialsandyforestecosysteminChina.Itisfoundatecotonebetweenforestandsteppe,oragriculturaldistrictandpastoralarea.Basedoninvestigation,thispaperdiscussedtheformationanddistributionofPiceamongolicaandstudieditsnatureaccordingtoecotonetheory.ItisclarifiedthatPiceamongolicabelongstoPiceameyeriseries.Thatistosay,itbecamealocalracethroughlong-termadaptationtothelocalclimate,thenformedallopatricsemi-species,andfinallyturnedintoataxonomicalspecies.Piceamongolicaforestisasuperzonalclimaxcommunitydevelopinginecotonebetweenforestzoneandsteppezone.

简介：在自然第二等的森林里的不同轻紧张下面的分数维的尺寸ofPiceakoraiensis幼苗的变化被学习。结果证明与轻环境的变化，王冠人物ofPiceakoraiensis幼苗在侧面的数字，侧面的增长，侧面的干燥重量，和特定的叶区域展出了更大的塑料。幼苗王冠的计算分数维的尺寸的范围在2.5728和2.1036之间被限制，但是分数维的尺寸的最大值在条款完成了中等shading，处于极端低轻条件，分数维的尺寸是最少的。

简介：Eightprovenancesof19-year-oldPiceakoraiensisNakaifromtheprovenancetrialsofMaoershan(45°20'N,127°30'E),Liangeshui(47°10'N,128°53'E)andJiagedaqi(50°24'N,124°07'E)inNortheastChinawereinvestigatedtoanalyzethegeneticvariationingrowthcharacteristics(treeheightanddiameter)andwoodcharacteristics(tracheidlength,tracheiddiameter,tracheidwallthickness,annualringwidthaswellaswooddensity).Greatvariationinheightgrowthandbreastheightdiametergrowthwasobservedamongtheprovenances,andalongwiththeincreaseoftreeage,theseprovenancespresenteddifferentgeographicadaptability.ThegrowthcharacteristicsofPiceakoraiensisstandatageof10inMaoershanandLiangshuiprovenancetrialshadapositivecorrelationwithlongitude,andwithincreaseoftreeageto15and19,thetreegrowthoftheprovenancesdisplayedasignificantpositivecorrelationwithlatitudeaswellasaltitude.Forwoodcharacteristics,greatvariationwasalsofoundamongtheprovenances.Thereexistsacloserelationbetweengrowthcharacteristicsandwoodpropertiesoftheprovenance.Theheightandbreastheightdiametergrowthoftheprovenancehadapositivecorrelationwithtracheiddiameterandannualringwidth,andanegativecorrelationwithtracheidwallthicknessandwooddensity.Geneticperformanceoftheprovenanceinallabovecharacteristicswasalsoinvestigatedinordertoprovidemoreusefulinformationforcomprehensiveselectionofthisspeciesforpulpwoodandplywoodproduction.

简介：Thelocaldamagessuchasknots,decay,andcrackscanbetranslatedintoareductionofservicelifeduetomechanicalandenvironmentalloadings.Inwoodconstruction,itisveryimportanttoevaluatetheweakestlocationanddetectdamageattheearliestpossiblestagetoavoidthefuturecatastrophicfailure.Inthisstudy,themodaltestingwasoperatedonwoodbeamstogeneratethefirsttwomodeshapes.Anovelstatisticalalgorithmwasproposedtoextractthedamageindicatorbycomputingthemodalflexibilitycurvaturebeforeandafterdamageintimbers.Thedifferentdamageseverities,damagelocations,anddamagecountsweresimulatedbyremovingmassfromintactbeamstoverifythealgorithm.Theresultsshowedthattheproposedstatisticalalgorithmwaseffectiveandsuitabletothedesigneddamagescenarios.Itwasreliabletodetectandlocatelocaldamagesunderdifferentseverities,locations,andcounts.Thepeakvaluesofthedamageindicatorscomputedfromthefirsttwomodeshapesweresensitivetodifferentdamageseveritiesandlocations.Theywerealsoreliabletodetectthemultipledamages.