云南引种桉树名录

本人简述了云南桉树引种沿革，列出１９９２年以前云南引种的８７种桉树名录，对云南引种桉树近百年的成效作了小结，为今后云南桉树引种工作提供依据。     

华南地区桉树可持续遗传改良与育种策略

从华南地区发展桉树工业纤维用材林对高产、优质、抗逆新品种需求的迫切性出发，分析了桉树引种成功之后遗传改良现状和存在问题，提出要实现华南桉树人工林可持续经营，必须建立和完善桉树长期可持续遗传改良体系，坚持以多世代群体遗传改良为基础，种间杂交无性转化利用为突破，加快育种增益转化为生产力的育种思路；强调新世纪桉树育种要重视常规育种与分子遗传研究相衔接，通过群体、个体、细胞和分子多层次多育种方式的相互交叉，充分利用各层次的遗传变异，提高育种效率。     

江西省桉树引种现状及发展策略

江西省地处亚热带地区,木材资源紧缺,土地资源也不富裕,林地年平均产出率又低(约每亩年产值5元左右)。因此,发展不与农作物争地的“高产出、优品质、高效益”的“三高”林业,是江西省林业发展的基本方向和出路。桉树引种近九十年历史,但良种使用率低,林分径营目的不清,产值不高,引种扩植基本上处于盲目阶段。本文以调查总结江西省桉树引种历史与遗传改良,开发利用现状,再从气候土壤特点和桉树的生物学特性,论述并西省桉树育种及发展策略。     

云南桉树引种,发展及丰产栽培技术简介

云南约1896年首次引种桉树,至1995年底,先后引种按树102种,种源239个,家系360个。树种增益17～69%,种源增益4～73%;营造桉树人工林13.433万 hm~2。桉树的引种和发展,为云南增加了新的种质资源,在绿化荒山,纸浆及纤维板生产,外贸出口,增加农民收入等方面起到了重要作用。     

福建省桉树人工林发展策略

福建省桉树引种始于1894年福州,继而桉树人工林在南亚热带中间地带的适生区逐渐发展。1986年起开展了多个树种及种源引种试验。目前全省已有以柠檬桉为主要树种的人工林0.937万ha,树种资源共30种。今后发展的策略是:正确的选择适合我省引种栽培的树种及种源,建立良种基地,进行遗传改良。在闽南沿海地区气候适宜水热资源优越的情况下,桉树只能在Ⅱ、Ⅲ类立地条件下种植,培育大径级材较困难,若以桉树为短周期工业用材林生产木片出口创汇为经营方针,注重早期集约经营合理施肥,加强科研成果的推广应用及开发多种利用途径,使科研成果尽快转化为我省的生产力。     

云南的桉树引种及对其发展状况的剖析

在概述中国桉树引种情况的前提下,全面论述了云南桉树引种历史、发展情况及在科学研究中取得的成绩,并对今后云南桉树发展提出了建议。     

云南造纸用桉树树种选择的研究

报道了云南桉树的引种、资源及桉树在造纸工业中的利用状况。结合云南的实际和国内外有关的文献资料,筛选出适于造纸的优良树种——蓝桉,和较好树种——直杆桉、柳桉。论述了影响桉树制浆造纸的主要因素——容重及抽提物。)     

生物技术在按树遗传育种中的应用

为全面了解现代生物技术在桉树遗传育种中的作用，本文概述了桉树组织培养，基因工程转化，桉树遗传图谱构建，数量性状位点（QTL）的定位，桉树DNA指纹图谱分析，分子水平系统发育研究，遗传结构和遗传多样性等方面的研究现状，探讨了生物技术方法和手段在改良桉树种质资源，培育新品种等方面的重要作用。     

雍文涛同志在国际桉树学术研讨会座谈讨论时的发言

此次桉树国际学术研讨会发表的研究报告,涉及到桉树的遗传改良、引种、栽培、以及桉树的特性,桉树木材的加工利用包括从最初产品到最终产品的加工生产等方面问题,与会代表进行了大量的交流与研讨,具有一定的广度和深度。对我国桉树的引种、栽培、发展、利用,将会有深远的影响,对我国林业改革发展也具有重要意义。     

林学会组团参加桉树在亚洲国际学术会议

广西林学会组织22人的代表团参加了由国家林业局桉树中心、澳大利亚农业中心、澳大利亚科工组织共同发起和组织的“桉树在亚洲国际学术会议”。该会议于2003年4月8～10日在广东省湛江市举行。出席这次会议的代表共170人,其中国外代表40人。这次学术会议分为亚洲桉树人工林发展、桉树遗传改良、桉树造林经营、桉树林生态环境、桉树加工利用等5个专题,内容涵盖了桉树引种、遗传育种、栽培管理、病虫害防治、桉树与生物多样性、桉树与地方恢复和桉树资源利用等领域,共收到论文100多篇,33位中外专家在会上作了学术报告。我区的项东云、庞正轰和…     

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.