丛生竹快速繁殖育苗和造林技术研究

研究丛生竹带篼埋杆育苗、埋节育苗、扦插育苗、以苗繁苗、应用GGR等育苗方法,探索不同立地条件、不同竹种的造林方法。观察了丛生竹“南竹北移”在江西西部的生长发育情况,提出丛生竹冻害等级和防冻措施。     

梁山慈竹埋节与侧枝扦插育苗技术研究

以梁山慈竹竹节和侧枝为试验材料,研究竹节年龄、部位、侧枝年龄、扦插基质、扦插时间和植物生长调节剂处理对育苗发笋率和成活率的影响,为湖南地区梁山慈竹埋节与侧枝扦插育苗提供参考.结果表明:2～3年生竹节育苗发笋率和成活率均高于1年生竹节,竹秆中部竹节育苗发笋率和成活率高于竹秆下部和上部竹节,竹腔灌注IBA溶液会降低竹节育苗...     

丛生竹无性繁殖育苗试验研究

近两年来,对分布云南境内用途较广的近20个丛生竹种进行了多种方法的无性繁殖育苗试验,结果表明,采用节间切口埋秆法(包括带蔸和不带蔸)和竹苗分株育苗法,其育苗成活率可达70％以上;龙头竹、黄金间碧玉、佛肚竹、绵竹等,用枝条扦插法育苗也能获得较高的成活率;生长素类药剂对龙竹、慈竹、绵竹等竹种的次生枝以及黄金间碧玉、油勒竹、甜龙竹的主枝有促进生根的作用,生根率可比对照提高20％～40％。     

丛生竹无性繁殖育苗试验研究

我们对云南境内分布较广、用途较广的近二十个丛生竹种进行了多方法多技术的无性繁殖育苗试验。试验证明,采用节间切口埋秆法和竹苗分株育苗法,选好苗圃地,加强管理,育苗成活率可达70%以上;某些竹种如龙头竹、黄金间碧玉、佛肚竹、棉竹等,用枝条扦插法育苗也能获得较高的成活率;生长素类药剂对龙竹、慈竹、棉竹等竹种的次生枝以及黄金间碧玉、油勒竹、甜龙竹的主枝有明显的促进生根作用,生根率可比对照提高20至40%。     

几种造纸用丛生竹秆节育苗试验

在福建省邵武市对椽竹、孝顺竹、坭竹等几种造纸用丛生竹进行秆节育苗试验表明，用平埋方法育苗显著优于斜埋和直插，竹蔸平埋效果更佳；不同竹种秆节育苗成活率存在明显差异；不同年龄的秆节育苗成活率在不同竹种间表现不同；不同育苗时间（３月或５月）的成活率差异不显著。竹秆不同粗细、不同部位、单节段或双节段育苗对比试验，结果以细秆（胸径２．５ｃｍ）、上部节段、双节段育苗成活率较粗秆（胸径４．６ｃｍ）、下部节段、单节段的为高。椽竹秆节径用不同激素处理后，处理间成苗率差异显著，以２，４－Ｄ２０ｍｇ／ｋｇ处理５ｈ和硼酸２０ｍｇ／ｋｇ处理２４ｈ的效果最佳。几种造纸用丛生竹秆节育苗试验＊张文燕周道三马乃训叶长青曹德友张华明     

几种造纸用丛生竹秆育苗试验

在福建省邵武市对橼竹、孝顺竹、坭竹等几种造纸用丛生竹进行秆节育苗试验表明，用平埋方法育苗显著优于斜埋直插，竹蔸平埋效果便佳；不同秆有苗成活率存在明显差异；不同年龄的秆节育苗成活率在不同竹种同间表现没；不同育苗时间（３月或５月）的成活率差异不显著。竹秆不同粗细、不同部位、单节段或双节段育苗对比试验，结果以细秆、上部节段、双节段育苗居活率较粗秆，下部节段、单节段的为高。橼竹杆节径用不同激素处理后，处理     

丛生竹带秆留节插枝创新育苗试验及造林初报

利用丛生竹地上部分的竹秆和枝条，通过人工整理和GGR处理，实行选竹枝、带竹秆、留竹节、竹筒灌水保温等一系列操作进行育苗。通过小型和中型育苗试验，得出坭竹、绿竹等多分枝、竹壁厚、体形较大的竹种采用此法育苗效果好，育苗成活率达85％以上，发笋成竹率达70％，每丛发笋成竹2株以上，造林成活率95％以上。     

大型丛生竹小苗分株育苗技术研究

2000～2002年在西双版纳普文基地对大型丛生竹版纳甜龙竹、勃氏甜龙竹、麻竹、杂交竹等苗木,进行了多次小苗分株育苗试验.结果表明小苗分株育苗平均产苗量比采用埋秆、埋节育苗方法提高成活率45%～80%,成本降低20%～30%,是丛生竹快速育苗中又一行之有效的技术之一.     

丛生竹扦插育苗影响因素研究进展

简述了近些年关于丛生竹扦插育苗内外影响因素的研究成果。重点针对竹种遗传性状差异和枝条类型、年龄、直径、枝序等扦插取材因素对扦插成活率的影响,合适的扦插时间、基质配比、激素处理等外部因素对扦插材料成活率的影响,以及内源激素、营养物质、酶活性等内部因素与生根的关系等内容进行了论述。     

丛生竹小竹蔸育苗过程中的假活现象

丛生竹育苗通常采用节秆埋节法、大竹蔸育苗法（竹根）、小竹蔸育苗法（竹枝）、种苗法（果实）等，但是，不同的竹种有着不同的生长结构组织和生育能力。实心竹肉质多，营养丰富，用小竹蔸育苗成活率也高；而空心竹肉质少，营养较少，用小竹蔸育苗成活率相对较低。根据这一特性，在一定的环境条件（温度、空气湿度、光照、土壤、水分等）下，我们可以建立如下数学模型进行分析。     

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.