不同基质和NAA质量浓度对药用观赏植物扦插生根的影响*

对蛇莓（Duchesnea indica）、翠云草（Selaginella uncinata）、过路黄（Lysimachia christinae）、垂盆草（Sedum sarmentosum）、活血丹（Glechoma longituba）5种药用植物进行扦插繁殖试验,研究了3种基质及NAA 激素3种质量浓度对5种植物扦插生根的影响。结果表明：蛇莓在不使用激素处理的条件下,田园土∶河沙＝1∶1的基质中生根效果最好,使用 NAA 处理后,泥炭土∶珍珠岩＝5∶1的效果最好;在100 mg／L NAA 的处理下,翠云草、过路黄在泥炭土∶珍珠岩＝5∶1的基质中,扦插生根效果最好;垂盆草在50 mg／L NAA 的处理下和田园土∶河沙＝1∶1的基质中进行扦插,其生根效果最好;活血丹在泥炭土∶珍珠岩＝5∶1和50 mg／L NAA 的条件下,生根效果最好。     

华北卫矛屋顶绿化基质筛选

由于屋顶绿化的特殊性,其对栽培基质的要求是容重轻、可支撑、有适宜的肥力,可以保证作物的正常生长。对华北卫矛屋顶绿化的栽培基质进行了筛选,以普通土壤为对照,在6种不同基质中筛选出基质A（体积比,土壤∶腐殖质为4∶6）,基质B（体积比,土壤∶腐殖质∶蛭石为4∶3∶3）,基质D（体积比,土壤∶腐殖质∶醋糟为4∶3∶3）为适宜华北卫矛生长的屋顶绿化栽培基质。     

屋顶绿化基质养分调控初探

提高基质保肥性能和优化肥料使用方式以降低养分流失,是屋顶绿化的关键环节之一。通过淋溶模拟和盆栽试验探究有机、化学肥料对屋顶绿化基质氮、磷、钾养分淋失的影响,结果表明:有机肥和复合肥15-15-15或缓释肥14-14-14配合使用可以在增加基质养分含量的同时,保持较低的养分淋失量,为垂盆草Sedum sarmentosum生长提供长期稳定的肥源;其中配合使用有机肥和复合肥效果最好,垂盆草定植快,叶绿素含量和肉质化程度指标也较优。     

不同无土栽培基质配比对3种草本植物生长的影响

采用草炭、草木灰、枯落物、腐殖质作为栽培基质来代替土壤,按照一定的体积比进行混合,制出4种无土栽培基质,并加入一定量的保水剂、鸡粪、磷酸二铵、硫酸钾;装入上为砂布下为无纺布制成的布袋中,将其铺于上下透气的钢丝网坪床上,并在其上撒播高羊茅（Festuca arundinacea）、披碱草（Elymus dahuricus）、紫花苜蓿（Medicago sativa）。通过对不同配比基质保水性能分析、植株的存活情况、株高、生物量情况的生长、生理指标进行观测研究,筛选出最适宜各个草种生长的无土栽培基质。试验结果表明：A3绿化基质是最适合披碱草植株生长的基质,A4绿化基质是最适合高羊茅植株生长的基质,A2绿化基质是最适合紫花苜蓿植株生长得基质。     

室内大厅立体绿化的植物材料及基质的选择

以花叶蔓长春花、毛鹃、散尾葵、桃叶珊瑚为植物材料,"轻型营养基质"为栽培基质,营造了室内大厅3个楼层立体花坛,进行了4种植物在不同位置、不同的光照环境下成活率测定以及生长状况观察。结果表明:4种植物耐阴性大小顺序为:桃叶珊瑚,散尾葵毛鹃花叶蔓长春花,成为室内立体绿化的植物和基质选择的一个样本。     

简单式屋顶绿化基质厚度筛选研究

薄层基质技术是降低屋顶负荷的关键,筛选满足简单式屋顶绿化植物生长和快速覆盖的最 小基质厚度显得尤为必要。通过蓄水盆栽培试验,研究了基质厚度2,4,6,8 cm 对八宝景天(Sedum spectabile)、佛甲草(Sedum lineare)、长寿花(Kalanchoe blossfeldiana)、吊竹梅(Zebrina pendula)、铺地锦 竹草(Callisia repens) 地被植物生长及覆盖效率的影响。结果表明：基质厚度越大,植物长势越好;基质 厚度为 8 cm 时,直立生长型植物八宝景天株高、根系体积、最长根长、地上部和地下部生物量均显著高 于其它厚度处理（P<0.05）;吊竹梅在基质厚度6 cm 时最快36 d 达到100% 覆盖,铺地锦竹草则在基质 厚度6,8 cm 时最快45 d 达到100% 覆盖;佛甲草、长寿花则生长较慢,基质越薄、成活率越低。综合 分析植物生长指标,建议八宝景天、吊竹梅、铺地锦竹草可选择最小基质厚度分别为 8,6 ,4 cm;佛甲 草、长寿花最小基质厚度则需要继续开展试验研究。     

适宜白腊生长的屋顶绿化栽培基质筛选

从苗木的生理特性变化方面对屋顶绿化树种白腊的适宜栽培基质进行抗旱性保水性能研究。从苗木生理指标大小推断出栽培基质的保水抗旱性优劣,以普通壤土为对照,在5种不同配比栽培基质中选择出基质(壤土∶草炭土∶蛭石∶珍珠岩=2∶1∶2∶1)为最适宜白腊生长的屋顶绿化栽培基质。     

园林废弃物堆肥产品对鸡冠花生长的影响

文章采用园林废弃物堆肥产品和园土按不同比例配制盆栽培养土,探讨其对鸡冠花生长的影响,以寻找园林废弃物堆肥产品作为花卉栽培基质的最佳用量。研究得出,适当比例的园林废弃物堆肥产品的添加可明显促进鸡冠花植株的生长,加强其观赏品质,但过量添加也可明显抑制其生长。本试验条件下,处理2(园土∶园林废弃物堆肥产品=3∶1)是鸡冠花的最优基质,可在鸡冠花栽培上的使用。     

不同醋糟基质配比对南方红豆杉幼苗生长的影响

为探讨醋糟与不同基质配比对南方红豆杉苗期生长的影响,遴选适宜南方红豆杉容器苗生长的复合基质配比,以南方红豆杉1年生苗为材料,设置10种不同配比的基质处理,测定不同配比复合基质性状特征,分析不同配比下南方红豆杉容器苗生长指标的变化。结果表明:醋糟基质可促进南方红豆杉苗株高、地径和总侧枝数的增长,且以醋糟∶锯末体积比为80%∶20%和醋糟∶锯末∶珍珠岩配比为60%∶20%∶20%2个处理的容器苗生长效果较好。醋糟可以替代泥炭作为南方红豆杉容器苗的轻基质;醋糟中添加锯末比例较高的基质不利于南方红豆杉容器苗的生长。     

容器育苗基质组成的研究

通过对２０个处理基质的分析，以及对容器苗生长影响的研究，确定了有利于苗木生长的最优基质配比。即：草皮土（黄心土）与砂、有机肥三者的体积比为８∶１∶１。基质组成与苗高、地径、侧根数均成正相关。     

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.