三门峡市常用绿化树种调森与分析

通过对三门峡市常用绿化树种现状的调查．对该市常见园林绿化树种共93种（含变种）的应用状况进行了初步分析,探讨了三门峡市园林绿化中存在的问题,并提出相应对策与建议,为提升三门峡城市绿化水平．合理规划设计园林绿地。特别是科学合理选择园林树种提供了依据。     

烟台地区七种引进绿化树种滞尘能力研究

对7种引进的高档绿化美化树种滞尘能力进行测定分析的结果表明,不同树种间滞尘能力存在很大差异,欧美海棠1号滞尘能力最强,挪威槭滞尘能力最差;城市在选择绿化树种时应优先选择滞尘能力强的树种。     

陕西20种主要绿化树种滞尘能力的研究

对20种常见绿化树种的滞尘能力进行了测定分析，表明不同树种问滞尘能力存在很大差异，乔木树种中广玉兰、国槐滞尘能力强，女贞和七叶树弱；灌木树种中石楠、大叶黄杨和海桐滞尘能力强，连翘和贴梗海棠滞尘能力差；常绿针叶树种中雪松、青杄滞尘能力强，龙柏和云杉滞尘能力弱。选择绿化树种时应优先选择滞尘能力强的。     

汕头市道路抗风绿化树种调查研究初报

通过2003年013号台风"杜鹃"袭击后,对汕头市道路绿化树种受害情况进行调查,分析了主要路树的抗风特性,并对汕头市道路绿化树种的抗风分级标准以及树种选择提出了意见和建议。     

汕头市抗风绿化树种调查研究初报

本文通过2003年013号台风“杜鹃”袭击后，对我市道路绿化树种受害情况的调查，分析了主要路树的抗风特性，并对我市道路绿化树种的抗风分级标准以及树种选择提出了意见和建议。     

北方城市停车场绿化树种选择

城市汽车保有量快速增长,使停车场成为城市建设中的一个重要环节,停车场绿化也引起了城市建设、环境保护单位的重视,本文就城市停车场绿化存在问题进行了分析,并提出了改进对策。     

汕头市主要绿化树种病虫害调查初报

本文对汕头市主要绿化树种病虫害发生情况进行调查，对为害较重的几种病虫害，提出相应的防治措施。     

水盐胁迫对上海常见4种绿化树种根系生长的影响

试验选取了上海较为常见的4种绿化树种,落羽杉、乌桕、栾树、喜树,针对上海泥质海岸沿海防护林的建设需要,对其进行了模拟海水的耐盐、耐水淹交叉胁迫处理。结果表明,栾树和喜树的根系在水盐胁迫环境中受到的影响比乌桕和落羽杉大,从根系表面积、长度、体积、平均直径来看,栾树和喜树的敏感程度比较大,均出现早期上升,中后期下降的情况。落羽杉和乌桕根系对环境的表现则不是那么明显。     

绿化树种对大气重金属污染物吸收净化能力的研究

研究测定了部分城市绿化树种对重金属大气铅、镉污染物的吸滞能力。结果表明:绿化树种对大气铅、镉污染物具有一定的吸收净化能力,并依污染气体和树种的不同具有明显差异;对铅吸收量高的树种有:桑树、黄金树、榆树、旱柳、梓树;吸镉量高的树种有:美青杨、桑树、旱柳、榆树、梓树、刺槐。     

10种亚热带绿化树种净化大气能力初步研究

通过对香樟(Cinnamonum campora)、广玉兰(Magnolia grandiflora)、银杏(Ginkgo biloba)、朴树(Celtis sinensis)、乌桕(Sapium sebiferum)、桂花(Osmanthus fragrans)、马银花(Rhododendron ovatum)、含笑(Michelia figo)、杜鹃(Rhododendron spp.)、三角枫(Acer buergerianum)10种亚热带绿化树种对大气中的粉尘、N、S、Cl 4种有害物质的吸收净化能力的初步测定,结果表明:单位面积滞尘量最高的树种是朴树,氮吸收最高的树种是乌桕,硫吸收最高的树种是银杏,氯吸收最高的树种是杜鹃;乔木树种的全氮含量、全硫含量、单位面积滞尘量都比灌木树种的含量高,但是全氯含量比灌木树种的含量低;落叶树种的各净化指标平均值都比常绿树种的高.     

Browsing damage on broadleaved trees in semi-natural temperate forest in Sweden,with a focus on oak regeneration

Absence of, or poor, oak (Quercus spp.) regeneration is a problem in uneven-aged, mixed closed-canopy broadleaved forests. Browsing by ungulates on small trees may contribute to poor oak regeneration in such forests. This possibility was investigated in 25 Swedish stands, and browsing damage was analysed in relation to landscape and stand factors. The proportion of browsed small (<20 cm tall) oak seedlings and other seedlings was low, and apparently a minor mortality factor. For saplings (20–130 cm tall), accumulated browsing damage was generally higher on oak than on five major competing tree species: Fraxinus excelsior, Corylus avellana, Tilia cordata, Acer platanoides and Sorbus aucuparia. Leaf removal was rare in late summer, except for rowan. The amount of cover (shelter) for ungulates near plots was positively correlated with oak browsing intensity; within plots, a high density of ash saplings may reduce browsing on oak saplings. In these forests, browsing probably retards growth of oak saplings relative to competing trees. Oak may persist as a minor stand component, but monitoring is needed to study future changes.     

Effect of density of trees on drag exerted on trees in river channels

Recently, riparian forests have attracted attention as they are effective for ecological preservation and landscape enhancement. Uses of such forests in flood prevention, sediment control, and erosion control works have been actively promoted. This study aims to clarify the effect of density of riparian trees on drag exerted on trees along river channels under the regime of bed load transport. Hydraulic model experiments were performed using a straight channel, and the methods to calculate the drag coefficient necessary for deriving drag exerted on trees were studied. Previous studies have stated that the drag coefficient of a cylinder is fairly constant when Reynolds number,R _e, is between 10³ and 10⁵ (e.g., Schlichting, 1979). This study clarified, however, that in cases of relatively dense arrangements of model trees (cylinders), the drag coefficient varies greatly with the density of the trees. As such, correlation between the drag coefficient and Reynolds number was found to be slight. Test results indicated that the drag coefficient of trees,C _d, correlates strongly with the coefficient of velocity,U′/U _* ′, friction factor of the channel bed,f′, and roughness concentration of trees × flow depth,aH′ or ratio of the area occupied by trees,λ. Furthermore, the drag coefficient,C _d, was also found to be slightly correlated with the gradient of the channel bed,I. Equations using either of the following parameters were obtained for deriving the drag coefficient,C _d, based on the experiment results:aH′; λ; U′/U _* ′; and Froude numberF _r. These equations allow fairly accurate calculation of drag exerted on trees.     

杨凌地区柳树行道树蛀干害虫危害及防治

本文通过对杨凌示范区城市园林绿化树种蛀干害虫危害现状及防治措施的调查,揭示当前关中地区城市园林蛀干害虫发生特点及主要应对策略,为城市园林中控制蛀干害虫扩散、危害提供决策依据。     

余姚市古树名木资源变化原因分析及保护策略

为更好地保护和利用古树名木,对余姚市古树名木资源10年来的变化情况进行了调查分析。10年内,古树个体数量新增80株,减少47株,净增33株,两次调查均无名木,主要表现为古树在农村区域增加,在城市区域减少。树龄进界是古树数量增加的主要原因,而自然灾害则是造成古树减少的主要原因。基于此,对余姚地区古树名木的保护提出了建议。     

北京市古树名木管理信息系统的设计与实现

根据北京市古树名木现有的数据资料和信息技术,设计并实现了一个基于Web的北京市古树名木管理信息系统。服务器端为管理者提供了一个功能完善的信息管理平台,客户端实现了对北京市区和郊区古树名木基本属性数据的查询,对病虫害防治措施的介绍和站内搜索,以及用户对一些信息的反馈和管理者的回复等功能。     

Observations on the rooting patterns of some agroforestry trees in an arid region of north-western India

The present study deals with root architecture of 6-year-old trees of 9 indigenous and 3 exotic species growing in arid climate of north-western India. Observations, made on excavated root systems (3 tree replicates of each species) showed large variation in horizontal and vertical spread of roots. In Morus alba, Melia azedarach and Populus deltoides, the roots were confined to 80 cm, while in Prosopis cineraria, Acacia nilotica and Eucalyptus tereticornis, roots penetrated more deeply to 233 cm. The number of total roots ranged from 103 in Acacia catechu to 1932 in Eucalyptus tereticornis, and 62 to 80% of the roots were less than 2 mm in diameter. The primary roots were more horizontal than the secondary roots. The total root biomass varied from 2.2 kg in Acacia catechu to 30.6 kg^–1 tree in Populus deltoides, and top 30 cm soil contained 42 to 78% of the total biomass. The implications of the results are discussed in the context of the ecological niche of the species, and its usefulness in agroforestry systems.     

安康市江南城区园林树木调查与评价

经调查,安康市江南城区园林树木共有46科73属92种,其中乔木61种、灌木29种、木质藤本2种,不同类型绿地树木种类数不同,居住区92种、单位绿化81种、公园广场绿化77种、城堤防护绿化35种、河道水景绿化27种、道路绿化23种、街头绿化小品22种,观赏特性方面,观花类种数占33%、观姿观干类占30%、观叶树种25%、观果树种12%。总体表现为安康市江南城区园林树木种类丰富,但无特色,树种搭配设计还需进一步提高。     

南京地区极端低温对常绿绿化树种景观的影响及分析

通过调查2004年冬季南京市7个不同地域常绿绿化树种所发生的冻害情况,分析了该地当年温度、降水等气候因子变化对常绿绿化树种景观效果的影响.     

园林工程移植大树的生长状况调查与分析

长春市不同绿地移植大树的生长状况调查结果表明：调查绿地移植的大树（平均胸径16．5～26．0cm）平均成活与趋向成活率只有60．8％,死亡和趋向死亡率却高达39．2％。2013年春季栽植的樟子松大树,平均胸径为11．8em的大树,死亡率为48．6％,而平均胸径为7．5cm的树木,死亡率只有3．5％。移植体量小的植株容易成活。     

抗生素对火炬松的器官发生植株再生的影响(英文)

本文研究了氨苄青霉素、羧苄青霉素和头孢霉素等3种抗生素对火炬松愈伤组织的生长和分化及不定芽生根的影响。结果表明,头孢霉素最有利于愈伤组织的诱导和生长,羧苄青霉素最有利于芽的分化,氨苄青霉素降低了不定芽的生根频率。所有试验的3种抗生素提高愈伤组织的形成和芽再生,但降低了芽的生根频率。这些结果表明,选择合适的抗生素对优化火炬松遗传转化体系有重要作用。图3表4参25。