木兰科植物在华东地区的引种评价

从全国14个省区收集到66种木兰科植物种子,育苗后定植于收集区中,通过栽培和适应性评价,在引种的7属66种木兰科树种中,37种生长良好,其中大多已进入开花结实期,另有15种不适应以至死亡,说明木兰科植物本园的引种保存基本是成功的。为造林绿化提供了基础。     

湖南野生木兰科植物资源及园林应用的探讨

为加速开发利用湖南野生木兰科植物资源，我们对此进行了广泛的调查研究。结果表明：湖南乡土野生木兰科植物6属33种，其中国家级保护植物8种。目前全省引种保存栽培的7属82种木兰科植物中，表现优良的园林绿化树种16种。     

安徽省木兰科植物引种驯化五十年综述

安徽省木兰科植物的引种驯化始于晚清,率先引种栽培的是广玉兰和白兰花;大规模的引种始于新中国成立后,并经历了60年代起始阶段、80年代中兴阶段和本世纪初的大规模、广区域引种阶段;50多年来,全省共引种驯化木兰科植物7属、60余种,比较成功的约有40余种,其中适于江南地区栽培的有7属、40余种,适于江淮之间栽培的有6属、约30种,适于淮北地区栽培的有4属、10余种。并对木兰科植物在园林绿化中的应用、花期链条构建、花色搭配以及病虫害防治、古树名木保护、特色药用品种原产地保护等,提出了一些具有创造性的对策。     

乐昌市木兰科植物的引种及保育研究

广东省乐昌市现有木兰科植物7属37种,其中乐昌市天然分布有5属14种,引种有6属23种。该研究总结了乐昌市引种的木兰科植物生长表现及保育中存在的问题,并提出了相关建议。     

木兰科植物引种试验初报

九江珍稀濒危植物种质资源库内木兰园，从1983年开始引种木兰科6属53种植物。经过5年多引种驯化栽培，生长理想或比较好的有46种，占引种总数的90％。本文介绍了各引进树种在新的环境条件下的生长发育表现，包括适应性、越冬性、越夏性，从而初步筛选出适宜于九江引种栽培的树种。     

贵州亚热带地区野生15种观赏植物引种观察

引种驯化栽培野生珍稀观赏植物11科14属（1亚属）15种，其中观叶类8科9属（1亚属）9种，观花类3科5属6种。主要特点是观叶类植物树（体）形美观，叶片奇异多样，四季浓郁；观花类植物花形多样，花色艳丽。所引种类容易栽培，能耐短期内-1～0℃低温，可作为公园、庭园、街道及旅游景点绿化的主体树种。     

珍稀濒危植物七子花的迁地保存

为保护国家稀有植物七哂花，进行了引种栽培，通过精心驯化、培育，获得引栽成功。     

北五味子育苗与栽培管理技术

北五味子育苗与栽培管理技术王福宗，刘彦茹，许金兰（河北省林业科学研究所，易县坡仓林业站）关键词北五味子，引种育苗，栽培管理北五味子（ＳｃｈｉｓａｎｄｒａＣｈｉｎｅｎｓｉｓＢａｉｌｌ），又名五味子、辽五味子、俗名山花椒。系木兰科五味子属多年生、落叶、木...     

木兰科稀有濒危植物种类迁地保护

应用迁地保护的原理和方法,在九江市林科所引种保存了木兰科植物6属54种(包括亚种、变种及杂交种),属我国重点保护的稀有濒危植物有13种,从而建立了具有相当规模的木兰科植物种质基因库。生长情况表明,木兰科植物在九江市林科所的迁地保护基本上是成功的。原产亚热带的木兰科植物种类一般生长良好。而原产温带或亚热带高海拔地区的种类则生长不良。     

湖南杜鹃属植物种类及引种适应性初探

在对湖南杜鹃属植物的野外调查、资料收集、标本鉴定的基础上,对其在湖南省森林植物园的引种栽培适应性进行研究。湖南产杜鹃属植物57种1变种,隶属5亚属8组14亚组,其中映山红亚属数量最,多达21种,占36.21%;湖南省森林植物园引种保存湖南杜鹃属植物38种,其中杜鹃亚属2种、常绿杜鹃亚属11种、马银花亚属8种、羊踯躅亚属1种、映山红亚属16种。引种栽培效果表明:马银花亚属在引种栽培中适应性最强,8种均表现为优良;原生分布海拔低的物种适应性高于相对海拔高的物种。分析探讨湖南杜鹃属植物在长沙地区的适应性,提出杜鹃属植物异地保育和开发建议。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.