浙西南野生观赏树木资源多样性

在对浙江省丽水市野生观赏树木资源调查研究的基础上，评价和分析了浙西南野生观赏树木种类的多样性，观赏特性的多样性，生长类型的多样性和园林用途的多样性，调查发现浙西南丽水市野生观赏树木资源丰富，全市共有野生观赏树种405种，根据观赏特性划分，有观花树木138种，观果树木108种，观姿树木76种，观叶树木72种，观枝干11种；按生长类型划分，有乔木155种，灌木196种，藤本41种，竹类1种，这些野生观赏树木可以在园林绿化中作为行道树或庭荫树栽培，也可作观赏树在园林中孤植或片植，用作垂直绿化和制作桩景，就浙西南野生观赏树木资源的合理开发和利用提出了建议。表1参3。     

苹果幼树碳素同化物运转特性研究 Ⅲ、改变库源关系对运转的影响

本试验利用去叶、去根和遮荫等措施,研究了改变库源关系对二年生红星短枝型玫瑰红苹果碳素营养物质运转的影响,结果表明:去叶显著提高了余留叶片~(14)C同化物初期(标记后三天)的输出率,从而造成大量的~(14)C同化物在主干和主根中累积。去根削弱叶片的同化功能,但促进~(14)C同化物向余留根系的运转。遮荫削弱叶片的~(14)C同化量,降低同化物初期输出率,还抑制根系的生长,使~(14)C同化物向根系的运输大为降低。去叶和遮荫对最终的输出率没有影响。     

古树名木调查方法的改进

从弥补古树名木调查方法的缺陷入手,通过在传统调查方法中引入全站仪、GPS等精密仪器和交叉定年技术,对调查方法的改进原理进行了探讨。比较和讨论2种调查方法,结果表明新的调查方法提高了树龄、树高、胸径和冠幅等关键数据的精度,并增加了地理坐标数据和多媒体信息的采集。图3参18     

城市旱垂柳平头后的腐朽规律与防控技术研究

研究牡丹江市城市旱垂柳立木腐朽菌种群的分布规律,发生发展状况及其对城市旱垂柳（Salix matsudana var．pseudo-matsudana y．l．Z）材的分解能力进行测定;对城市旱垂柳林的立木腐朽防治技术进行对比分析。研究结果表明：城市旱垂柳具有发达的愈伤组织系统、树皮保护系统,萌芽能力和生根能力特别强,根系发达等许多优良品质,因而其生命力特别顽强,抵御病虫害毁灭性打击的能力很强,它是城市森林的优质高效树种;城市旱垂柳林容易遭受人工整枝、整形、平头、机械伤害等强烈的干扰,导致17种以上木材腐朽菌的侵入,腐生率与林龄（胸径）呈正相关,随林龄的增大腐生真菌的种类相应增多,但死亡率较低;测定的毛革盖（Coriolus hirsutus（Wulf．：Fr．）Quél．）等8种旱垂柳木材腐朽菌的降解能力排序为：毛革盖,云芝,香栓,多毛盖菌,单色下皮黑,桦革裥,树舌,黑管菌。对旱垂柳林施行的一切园林技术措施都必须有利于其愈伤组织的快速愈合,以及树皮系统的尽力保护。     

Diversity of street tree populations in larger Danish municipalities

Healthy and sustainable tree populations require a high diversity of genera and species. This study examined the occurrence and contents of tree inventories in Denmark's 30 largest municipalities. 59% of the municipalities had a tree inventory for street trees, but only about half of these were complete and updated. Only one municipality had a registration for trees other than street trees. Based on data from the tree inventories, the diversity of road side trees was analyzed at genus level and species level. A total of 82,072 street trees are part of the study. 11 different genera account for 92% of the total street tree stock, and 2–6 genera account for 40–80% of the street tree stock in the individual municipalities. Tilia was the most dominating genera (26%). 12 species account for 73% of the total street tree stock. The 6 most common species account for almost 50% of the total tree population. The species representing the largest numbers were Tilia × europaea (12%), Acer platanoides (10.9%), Platanus × acerifolia (7.2%), Tilia cordata (7.2%), Fraxinus excelsior (6.2%) and Sorbus intermedia (5.9%). The four most urbanized municipalities had a surplus of non-native species, but all municipalities apart from one had most street trees belonging to native species. The concluding recommendation of this study is that tree managers need to start working more strategic with their tree stock, in order to reduce the vulnerability, due to potential attacks from pests or diseases and climate change effects. A risk spreading system for the urban tree population is proposed, suggesting that no genera should account for more than 10% and no species for more than 5% of the tree population.     

A citywide survey of the pine processionary moth Thaumetopoea pityocampa spatial distribution in Orléans (France)

There is a growing recognition that urban trees provide various valuable benefits and services such as enhanced human wellbeing. However, they also have a cost in terms of public health either directly (allergies) or by harboring species representing health risk for humans. This paper focuses on such a forest insect species, the pine processionary moth Thaumetopoea pityocampa. Its caterpillars develop gregariously during winter in a conspicuous silk nest in coniferous hosts. When disturbed, the larvae release urticating hairs that cause human or animal serious health problems. The purpose of our survey was to (1) inventory all individual trees belonging to potential host species and estimate the density of T. pityocampa (2) assess the spatial pattern of the insect population at the city scale. We conducted an exhaustive inventory of potential coniferous host trees in five municipalities (ca. 5000 ha) in the north of Orléans, France. Each tree was identified, geo-referenced and the number of moth nests it hosted was counted. A total of 9321 urban trees representing 11 coniferous taxonomic units were investigated. The distribution of T. pityocampa exhibited a marked spatial structure citywide. Geostatistics allowed to draw risk maps revealing strong patchiness. We provide the first estimate of T. pityocampa host tree preference in an urban context and found that Pinus nigra, P. pinaster and P. sylvestris were the most attacked trees. We also report numerous cases of T. pityocampa occurrence on the exotic ornamental Himalayan cedar Cedrus deodara. The management implications of our findings are two-fold: (1) risk maps constitute a useful framework for communication and public information, and can help developing control strategies; (2) some species frequently used for ornamental purposes are poor quality hosts regarding T. pityocampa and should therefore be preferred in public place usually frequented by vulnerable people (schools, nurseries, hospitals).     

果树在园林植物造景中的应用

本文分析了果树在园林植物造号中利用率低的原因,阐述了果树在各类绿地园林植物造景中的选择配置与应用,以及果树作为园林植物造景树种应注意的问题,并简要介绍了园林绿化或造景中几种常见的果树。     

旅游区人为干扰对森林群落物种多样性的影响

研究人为干扰对湖北省梭布垭石林针阔混交林森林群落物种多样性的影响。结果表明,人为干扰对乔木层马尾松Pinus massoniana和杉木Cunninghamia lanceolata优势种的主体地位和作用没有根本性的改变,但使群落平均胸径（或地径）和平均树高降低,群落种类组成发生变化。重度干扰和中度干扰降低了群落乔木层阔叶树种和灌木层优势种的作用和地位,重要值降低,但增加了群落物种多样性水平。不同干扰类型的群落,在垂直高度1.0 m以下,Shannon-Weiner多样性指数较大,1.1 ~ 3.0 m高度达最大,以后随高度升高,多样性指数降低,在9.1 m以上的高度层,树种单一,多样性为０。图3表3参13     

果树无病毒研究进展

结合国内外研究,介绍了当前果树生产上应用的4类主要的无病毒技术,即物理疗法、化学疗法、微茎尖法和转基因技术的操作过程和特点,指出脱毒药品开发和抗病毒转基因的研究,将是今后无病毒技术研究的主要领域。     

淳化县泥河沟流域果林发展与综合效益遥感动态研究

利用不同时期遥感信息资源、结合实地调查测绘，编制不同时期果林类型图，经过叠合比较，建立动态分类系统，获得果林类型动态图，以此分析淳化县泥河沟流域１９８６￣１９９５年果林面积的动态变化与综合效益。