几个外来优良庭园绿化树种的无性繁殖技术

荷花玉兰、菩提树下垂白千层3个外来庭园绿化树种，观赏价值高，但种源不同。在广西繁殖材料有限，为开发这些树种，总结出破枝压条、圈枝压条和扦插等快速无性繁殖技术。     

7个常见绿化树种的抗逆性研究

通过对花曲柳、黄栌、火炬树、山杏、复叶槭、卫矛、五角枫等7个树种进行不同程度的水分胁迫处理和遮阴胁迫处理,进行相关生理指标测定,初步探讨了这7个树种的耐旱性及耐阴性特点,结果表明：五角枫、花曲柳、复叶槭的抗脱水能力较强,是较为耐旱的树种;卫矛、花曲柳、复叶槭和火炬树表现出很好的耐阴性,黄栌和五角枫的耐阴性较差,山杏具有一定的耐阴性,但遮阴强度不宜过大。     

我区又添绿化观赏新树种美丽异木棉的引种及矮化

美丽异木棉原产南美洲的阿根迁，由于有独特的珍、稀奇形态和环保功能，近年各国都争先引种。在我国引种较早的是台湾省嘉义市、海南省尖峰岭热林所和广东华南师大，但是比较系统详细的引种研究论述，却难觅踪迹。     

北方地区优良的观果树种

随着城市的不断进步,园林绿化已作为衡量一个城市进步与否的重要标准,所以各城市的园林绿化越来越受到重视,一改过去那种单纯以绿色为主的绿化格局,逐渐向彩色与绿色的协调配置过渡.现在彩叶植物已受到人们的青睐,并且其发展趋势越来越好.例如:紫叶矮樱、美国红栌、紫叶稠李、金叶垂槐、日本红枫、金叶女贞等已经在园林绿化中得到应用,且其绿化效果颇佳.而一些优良的观果树种还没有受到人们的重视,观果树种作为一种独具特色的绿化树种,具有着很大的发展潜力.     

4个观赏树种对紫外线屏蔽效应的研究

应用地表植被光谱仪测定紫薇、山茱萸、柳叶栎、北美红栎4个观赏树种的光谱日变化特征。结果表明:各树种对太阳总辐射屏蔽效率的日变化呈"增加"的趋势,对UVA辐射、UVB辐射屏蔽效率的日变化呈"增加—降低"的趋势。80%以上的太阳总辐射、UVA辐射、UVB辐射都被屏蔽,4个树种具有良好的屏蔽紫外线辐射的功能;紫薇对太阳总辐射、UVA辐射、UVB辐射屏蔽效率都最高。     

城区绿化值得推广的几个树种

1、白皮松 属松科,松属。常绿乔木,系中国名贵树种。树形多姿,苍翠挺拔,别具风格。树干斑驳状,呈乳黄色而有光泽。于干下部尤为显著,至上部则渐变为粉白色,视之闪灿作光,斑斓可爱。 耐干旱,较耐寒,喜欢生长于土质较干燥,排水良好之地。对二氧化硫及烟尘污染有较强的吸附性。 2、雪松 属松科,雪松属。常绿乔木,树冠呈塔形,大     

4个北美树种在辽西地区的引种试验研究

为了丰富本地区的树种资源,满足园林绿化对树种多样性的需求,从物候期、生长节律及光合特性等几个方面对美洲朴、毛核木、银水牛果、西部沙樱这4个北美树种在辽西地区的引种适应性进行了研究。结果表明,4个树种的萌芽、展叶期均较北京地区有所延后,花期则提前;美洲朴未见开花坐果,银水牛果秋季叶片不变色;4个树种株高、地径、枝条的快速生长期为5—7月份,美洲朴和毛核木具有明显的越冬枯梢现象,翌年生长多以萌蘖条为主;西部沙樱和银水牛果具有较强的光合作用和较高的水分利用效率,是辽西地区园林绿化可尝试引入的优良观赏树种。     

基于隶属函数法的3个观赏树种抗寒性综合评价

为了探讨低温胁迫对西伯利亚花楸(Sorbus sibirica)、天山花楸(Sorbus tianschanica)与欧洲荚蒾(Viburnum opulus)3个观赏树种渗透调节物质含量及抗氧化保护酶活性的变化,设-15(对照)、-20、-25、-30、-35和-40℃等6个低温处理,分别测定了这3个树种可溶性糖(SS)、可溶性蛋白(SP)、脯氨酸(Pro)、丙二醛(MDA)、相对电导率(REC)含量和超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)等保护酶活性。结果表明：随着温度的下降,西伯利亚花楸SS含量峰值出现在-40℃处理,出现较晚,抗寒性较强;在-40℃处理中西伯利亚花楸与欧洲荚蒾SP含量分别高于对照11%和27%;3个树种Pro高值均出现在-40℃处理中,其中最高为西伯利亚花楸,为0.016%,其次为欧洲荚蒾(0.013%)和天山花楸(0.010%);天山花楸-40℃处理枝条的MDA含量较高,为0.089μmol·g^-1,说明其受低温伤害程度较重;-40℃处理西伯利亚花楸REC最低,其次为天山花楸;在-40℃处理中3个树种SOD、...     

优良景观保健树大叶冬青的绿化应用

文章报道大叶冬青的主要生物学特征和优良景观绿化价值及景观保健功能,结合笔者的研究结果论述了大叶冬青的抗菌、抗衰老、抗癌保健功能,从景观保健绿化和药用保健产业开发角度认为大叶冬青是一个优良的景观保健常绿树种,在城乡绿化建设和相关产业开发中具有应用潜力,并报道了相关栽培技术。       

Biomass equations for sixty-five North American tree species

The paper presents a comprehensive review of the biomass equations for 65 North American tree species. All equations are of the form M = aD^b, where M is the oven-dry weight of the biomass component of a tree (kg), D is diameter at breast height (DBH) (cm), and a and b are parameters. Equations for the following tree components were included in the review: total aboveground biomass, stem wood, stem bark, total stem (wood and bark), foliage, and branches (wood and bark). A total of 803 equations are presented with the range of DBH values of the sample, sample size, coefficient of determination R², standard error of the estimate, fitting method used to estimate the parameters a and b, correction factor for a bias introduced by logarithmic transformation of the data, site index and geographic location of the sampled stand(s), and a reference to the paper in which the equation (or the data) was published. The review is a unique source of equations that can be used to estimate tree biomass and/or to study the variation of biomass components for a tree species.     

6种园林树木对持续性淹水胁迫的生理响应及其比较

以榔榆、榉树、朴树、女贞、枇杷、珊瑚树2年生幼苗为材料,采用盆栽控水试验研究了持续淹水对不同树种外部形态及主要生理指标的影响,探讨了不同树种的抗涝性特性与差异.结果表明:1)淹水胁迫下,不同树种幼苗的生长均受到不同程度的影响,外形表现出明显的水渍斑点和黄化特征,但不同树种受害程度存在一定差异.2)淹水胁迫下,不同树种2种保护酶活性呈现出不同的变化态势.榔榆叶片抗氧化保护酶的活性反应最为敏感,表现为淹水初期SOD活性的显著上升和POD活性的剧烈增加,但后期两种保护酶活性趋于平缓变化;榉树、朴树在整个淹水期SOD活性呈现先期下降后期抬升的波动变化;而女贞、珊瑚树在整个淹水期SOD、POD活性的变化相对较小,不同处理期的测定值差异均不显著.3)榉树、朴树的游离脯氨酸含量变化呈现前期略有下降后期缓慢上升的变化;而女贞、枇杷两树种的游离脯氨酸含量变化呈现先期下降,后期平缓变化的态势.4)淹水初期榔榆MDA含量明显上升,并于淹水第13天时含量最高,榉树和朴树的MDA含量变化呈现先期下降后期缓慢上升的变化,枇杷、女贞的MDA含量变化几乎呈一直线变化.5)6树种叶片中叶绿素含量均随淹水时间的延长而下降.采用隶属函数法对6种树种的耐涝性进行评估,其耐涝性强弱大致排序为:女贞、枇杷、珊瑚树、朴树、榉树、榔榆.     

Properties of boundary-line release criteria in North American tree species

? Boundary line release criteria are increasingly applied to evaluate forest disturbance histories from tree-ring data. However, a number of important properties central to the technique have not been evaluated, including: (i) the ability of boundary line release criteria to standardize releases across various sites, species, and tree life stages (ii) the minimum sample sizes necessary for developing boundary lines, and (iii) the degree to which the criteria can resolve the degree of crown exposure following a disturbance event.

? In an analysis of eleven North American tree species, boundary line release criteria do not fully compensate for declines in release response a tree experiences with increasing age and size, with the exception Tsuga canadensis.

? A bootstrapping analysis indicates that approximately 50 000 ring width measurements are necessary to develop boundary line release criteria for a given species.

? In a Quercus prinus stand, boundary line release criteria better predict the degree of crown exposure following a disturbance than an earlier running mean technique.

? Despite certain limitations, boundary line release criteria have the potential to standardize release calculation across most life stages of a tree, and possibly among sites and species.

     

观花乔木树种在沈阳街路推广与应用

通过对沈阳市街路栽植的观花乔木的现状分析,确定了观花乔木的引种与筛选原则,对初选出的近30种观花乔木进行了各种观测试验。基本摸清了这些观花乔木的生物学特性和生态习性;通过应用栽培试验,筛选出栾树、香花槐、红肉苹果、暴马丁香等26种优良观花乔木树种;列出了适合沈阳街路栽植的观花乔木树种名录并进行了推荐。     

Snag degradation pathways of four North American boreal tree species

Many studies have highlighted the importance of deadwood, whether standing (snags) or fallen, in boreal ecosystems dynamics. However, a dearth of literature exists regarding the persistence and degradation pathways of these structures in northeastern American boreal species.     

观赏果树在园林绿化中应用前景展望

观赏果树是从传统果树中派生出来的一个特殊种群,这个种群在叶、花、果实、干形中某一方面或几方面更具有观赏性,更适合园林绿化之用。现就观赏果树的概念、国内外发展现状、发展观赏果树的优势、观赏效果、存在的问题及解决对策、前景展望等几个方面进行了阐述。     

优良观赏保健树大叶冬青引种试验初报

引种研究结果表明,大叶冬青种子休眠期长,需处理18～24个月才能萌发,幼苗期生长缓慢,生长呈双峰型,2次抽梢明显。树高季节生长高峰一般在4月和7～8月出现,绝大多数植株6月生长趋于停滞;地径季节生长分别在5～6月和8月出现峰值。季节生长与月均温、月降雨量、月均相对湿度呈正相关显著,表明生长需要较高温度和湿润的条件。幼龄期适应性强,能适应引种地35～39℃极端最高温度和冬季-5～-7℃自然低温,安全越夏越冬,未见病害发生。苗木栽植后3a开始速生,速生期年生长量达50cm以上。采用金丝垂柳(J842)、杜仲、南酸枣等阔叶树种与大叶冬青复层混交,利用侧方遮荫作用,能显著促进大叶冬青生长,并提前2a速生,树高净生长量增加19．65％．34．20％,4年生苗平均高1．60～2．07cm,地径2．0～2．3cm;叶用园幼树3年生春季嫩叶产量达150kg／hm^2,4～5年生春季产嫩叶225～281．75kg／hm^2,生产优质苦丁保健绿茶60～112．5kg／hm^2,显示出研发利用的潜力。     

Wood specific gravity of some tree species in the Garhwal Himalayas,India

Estimation of terrestrial biomass depends critically on reliable information about wood specific gravity of forest trees. In recent years, wood specific gravity has become more important when exploring the universality of functional traits of plants and estimating their global carbon stocks. To estimate their specific gravity, wood samples were collected from a total of 34 tree species, 30 from lower elevations and 4 from upper elevations in the Garhwal Himalayas, India. The results show that the average wood specific gravity was 0.631 (ranging between 0.275 ± 0.01 and 0.845 ± 0.03) for the species at lower elevations and 0.727 (ranging between 0.628 ± 0.02 and 0.865 ± 0.02) for the upper elevations. The average wood specific gravity for the upper elevation species was 9.6% greater than that for the species at lower elevations. Aegle marmelos among the lower elevation species and Quercus leucotrichophora among the upper elevation species had the highest wood specific gravity, which were 0.845 ± 0.03 and 0.865 ± 0.02, respectively.