长白旱麦瓶草的引种繁育技术研究

以长白山高海拔地带分布的野生长白旱麦瓶草为材料,开展引种繁育技术研究。结果表明,长白旱麦瓶草从海拔1 400 m的原产地引种至海拔730 m的二道白河,垂直高度下降了1倍,生长发育正常;单花期6 d,群花期5月21日至9月15日,较原产地延长了50 d,增加了观花时间。播种繁殖和分株繁殖均可。     

武汉植物园樟科植物引种适应性评价

对武汉植物园引种成功的樟科植物进行了统计,结合植物园近年的樟科引种记录,对中国樟科植物在武汉植物园的适应性进行了分析。结果表明:樟科植物中,在原产地分布范围广、分布密度大的物种,具有更好的适应性,引种成功率高;在各属中,樟属、黄肉楠属和山胡椒属引种成功率最高,琼楠属引种潜力最大。     

试谈把厦门建成“椰风海韵”的热带海滨城市的构想

根据棕榈科植物的生长特点、景观特色和应用价值,结合厦门的自然地理条件以及棕榈植物在厦门的引种驯化、景观配置的实践经验,按照厦门市绿化规划构想,提出并论证了大量应用原产热带海岛的棕榈植物以改造本岛植物景观,把厦门建成“椰风海韵”、特色明显的热带海滨城市的构想。 所谓特色,就是有明显的个性、独特的     

棕榈科植物主要病虫害防治

棕榈科(Palmae)植物约有210属2800种,分布于热带、亚热带地区,主产热带亚洲及美洲,少数产于非洲。我国原产及引种栽培的共约250种,主要分布在云南、海南、广东、广西和福建等省地。 随着棕榈植物的广泛栽植,其病虫害种类及其危害的严重性也逐渐增加,成为棕榈栽培与管理中不可忽视的问题。现对发生严重的几类病虫害提出防治措施。     

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。     

长林系列品种油茶籽含油率和脂肪酸组成分析研究

对10个引种栽培的长林品种油茶籽含油率和脂肪酸进行了测定.结果表明:采果时间对含油率影响大,不同品种间含油率差异显著.长林3号含油率比原产地高0.80％,长林4,18,23,27号引种后含油率与原产地差异不大,审定的长林3,4,18,23号和27号比对照分别大10.10％,4.65％,6.35％,11.63％和10.51％.油茶籽油脂肪酸主要由油酸、亚油酸、棕榈酸和硬脂酸4种脂肪酸组成.油酸含量在72.40％～84.70％,均值为79.34％;亚油酸含量在4.30％～15.50％,均值为9.47％;棕榈酸含量在6.60％～9.00％,均值为7.75％;硬脂酸含量在1.20％～3.10％,均值为2.03％.     

耐寒棕榈科植物的北方园林应用建议

棕榈科是世界上3个最重要的经济植物类群之一,也是最为独特的观赏植物。文章介绍了棕榈植物中耐寒种类的地带性分布和部分相对较耐寒的棕榈植物,提出了棕榈科植物中耐寒种类应用研究的一些建议。认为耐寒棕榈科植物在北方园林上的应用,是需要一个复杂的引种和科研过程,涉及到棕榈植物的抗寒性、抗冻性和抗旱性等。因此,引种和应用上要谨慎行事,综合各种相关因子,最好从多渠道、多方位进行引种试验,以防遭受不必要的损失。     

云南的辣木引种试验初报

在云南的开远、东川、永仁、思茅、瑞丽5地进行了8个种源,2个品种的辣木引种试验,所引种的辣木其幼树期表现出生长迅速,能正常开花结实的状况;且所引种的10个种源(品种)间生长差异并不显著。辣木定植后,呈现持续生长的状态,无明显缓苗期;年生长态势在年内大部时间生长迅速,到11月初随着温度的下降而生长减缓,粗生长在后期增长明显加快。表明辣木生长受温度影响较为明显,对温度的变化较敏感。引种的辣木植株1年生枝耐修剪,显示其为易于更新的树种。另外,引种的辣木叶中蛋白含量与原产地基本相同,但钙、钾、镁等微量元素的含量低于原产地,而维生素含量则高于原产地。     

棕榈科植物在厦门的引种栽培及其应用

从棕榈的幼树培育和移植后的管理等方面阐述了棕榈引种栽培的主要技术,并对它们在多方面的应用作了初步的总结,为该树种在厦门的引种栽培和科学管理以及园林绿化等方面提供参考。     

德宏州棕榈科植物资源及其分布特征研究

通过对德宏州棕榈科植物进行野外重点线路调查,统计其分布区类型,采用植物区系学的研究方法对其地理区系特征进行分析,结果表明,德宏州是云南及中国棕榈科植物资源最为丰富的地区之一。该区共有棕榈科植物10属36种及变种(不含栽培种),其中省藤属13种,蛇皮果属、刺葵属为单种属。棕榈科中中国特有分布8种,其中,云南特有分布5种。以盈江(中缅)边境地区海拔240～1 000 m为德宏棕榈的密集分布区,海拔2 000 m为分布上限。德宏棕榈植物的种类以热带亚洲分布类型为优势,具有明显的印度-马来成分特点,与缅甸(13种共有种)及滇南(西双版纳)热带有着非常密切的联系,同时该区具有明显的热带边缘分布特征。     

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.