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亮果桉[Eucalyptus nitens(Deane ＆ Maiden)Maiden]在分类学上与蓝桉(E.glo-qulas Labill)和多枝桉(E.viminalis Labill)亲缘关系密切,同属于双蒴盖亚属(Sgm-phyomyrtus)蓝桉组。亮果桉是桉树属中高大乔木树种之一,是澳大利亚高大桉树林的重要组成树种。树高通常40-70m,偶见高达90m,胸径1-2m,树干饱满通直。亮果桉的地理分布呈现出典型的地理间断特征,种群之间彼此隔离,因此其形态特征,尤其是幼态叶的特征产生明显的种内地理变异。它分布在澳大利亚的新南威尔土和维多利亚4个相互隔离地区。水平分布的地理纬度范围为30°-38°S,垂直分布海拔 相似文献
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《Southern Forests》2013,75(4):319-328
Harvested logs supplied from five fibre-managed Eucalyptus nitens plantation coupes with different growing environments were assessed for quality and stiffness. Billets extracted from the logs were rotary peeled for veneer. When averaged across the five coupes, 30% of veneer recovered could be used directly in structural plywood production and an additional 20–25% could be used after further processing. In visual assessment most veneer was assigned an Australian/New Zealand Standard AS/NZS2269.0:2012 Quality D. Acoustic testing during processing showed veneer peeled from a drier and lower elevation coupe had significantly higher dynamic MOE values than veneer processed from logs harvested from wetter higher elevation coupes. To examine the utility of the E. nitens peeled veneer in the production of structural plywood, it was combined with veneer of a known higher stiffness, rotary peeled from regrowth forest Tasmanian oak species logs. Structural seven-ply panels were manufactured from the veneer prepared in three different ply arrangements. Mechanical testing of the panels in accordance with AS/NZS2269.0:2012 showed that an F17 target stress-grade panel product of 83% E. nitens and 17% Tasmanian oak species could be produced, if E. nitens veneer of higher stiffness were selected from veneer segregated by estimated dynamic Modulus of Elasticity value. Panels with 50% E. nitens and 50% Tasmanian oak veneer could be produced by selecting E. nitens veneer of lower stiffness after segregation. In the majority of panels tested stress-grade rating was limited by perpendicular bending strength. Outcomes from the study indicate that structural plywood can be manufactured using differing proportions of E. nitens veneer, rotary peeled from fibre-managed plantations, provided it can be segregated into stiffness categories and selected to achieve a target stress-grade. 相似文献
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本文比较了诱导生长在温室的光亮桉苗木水分胁迫的灌水方法，第一种方法分为隔３ｄ给苗木灌水（土壤水分达田间持水量）或者不灌水，第二种方法采用每天定量给苗木灌水，水量分为３０ｍｌ和１０ｍｌ。结果表明每天给苗木定量灌水１０ｍｌ使苗木缓慢产生水分胁迫，并且不同苗木之间的水势误差小，测定精度高，更符合田间苗木的水分胁迫情况。所以１０ｍｌ的灌水方法是诱导温室光亮桉苗木水分胁迫的好方法。 相似文献
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１９８６～１９９２年由澳大利亚提供史密斯桉种源１２个，亮果桉种源１７个，分别在保山、昆明、楚雄进行史密斯桉、亮果桉的种源选择试验。试验结果表明：史密斯桉、亮果桉存在种源差异；从生长量、生长稳定性、抗逆性、桉油含量等方面进行综合评定认为，史密斯桉１５５４４、１５０９２、１２１３１种源，亮果桉１２４０１、１３２８１、１４４４９、１６６３６、１６７５０种源是表现较好的种源，４～６年生史密斯桉优良种源，与直干桉对照相比，蓄积量的平均实际增益为５８％；而３～４年生亮果桉蓄积量的平均实际增益为７３％。史密斯桉含油量增益为５７．４％。试验选择出以上述两树种种源可在适宜地区推广。 相似文献
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海湾网箱养殖斜带髭鲷的生长特性 总被引：1，自引：0，他引：1
2002～2005年期间在广东省饶平柘林湾海上网箱采集斜带髭鲷Hapalogenys nitens标本共515尾,以鳞片的年轮作为年龄鉴定依据,对其生长特性进行研究。结果表明,1～5龄鱼体长与鳞长的关系式为L=175·17r 227·22,体长与体重关系式为W=0·0001L2·8677,体长与全长的关系式为Lt=1·1736Lb 3·6206,应用von Berta-lanffy生长曲线拟合生长规律,求得斜带髭鲷的各项生长参数为渐进体长L∞=452·418mm,W∞=4315·455g,体重生长曲线的曲率k=0·2799,理论上体长和体重为零时的年龄t0=-1·1869龄,体重生长拐点年龄t0=2·738龄。 相似文献
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[目的]对患病斜带髭鲷(Hapalogenys nitens)幼鱼进行病原菌的分离及鉴定。[方法]对2013年1月福州罗源湾某海水网箱养殖场斜带髭鲷幼鱼死亡病例进行了发病情况、临床表现及病原学方面的检验;对其中5尾患病斜带紫鲷的肝脏、脾脏、肾脏及鳃丝进行细菌分离与纯培养,对病原菌进行形态、生理生化测定和16S rRNA基因序列测定及系统发育学分析,并用30种抗菌类药物对5株菌进行了药敏试验。[结果]斜带髭鲷幼鱼死亡病例为细菌性感染症,分离纯培养的菌株(fzlyw201301071和fzlyw201301072)与弧菌属(Vibrio)的鱼肠道弧菌(Vibrio ichthyoenteri)可认定为同一种属。药敏试验结果显示,在不同菌株间无明显的敏感与耐药性差异。[结论]为水产养殖动物的疾病防治提供了理论依据。 相似文献