欧洲云杉扦插育苗技术研究

欧洲云杉[Picea abies（L．）Karst]是松科云杉属树种。分布欧洲中部和北部地区，较耐寒，喜湿润，对土壤要求不严。树干通直，材质好，生长较快，病虫害较少，具有较强的抗逆性和适应性，是优良的园林绿化观赏树种，也是挪威、奥地利、德国等14个国家的主要造林树种。从1983年起，“国内外重要造林树种引种驯化”列人国家“六五”和“七五”科研攻关课题，由中国林业科学研究院林业研究所组织全国50多个科研、生产和管理单位共同开展林木引种攻关。     

云杉引种及种源试验研究

经长达１４～１５ａ的云杉引种和红皮云杉种源试验研究表明：青海云杉从西北引入齐齐哈尔北部克拜地区造林是成功的，生长良好，树高、胸径、材积分别比对照大４．１％、１５．０％和１９．８％；红皮云杉美溪种源在该地区生长量高，生长稳定，为最佳种源，树高、胸径、材积分别比对照大５．０％、１１．９％和２７．１％；云杉早期选择是可行的，５～６ａ可作为早期选择的初选年龄。     

蓝云杉、欧洲云杉、白云杉在甘肃中部干旱半干旱区的适生性评价

为扩大蓝云杉(Picea pungens)在甘肃的栽培范围,利用甘肃小陇山国家云杉种质资源库的蓝云杉、欧洲云杉(Picea abies)、白云杉(Picea glauca),在甘肃中部干旱半干旱区(临洮)自然条件相对较差、树种资源匮乏的地区有针对性地引进国外云杉树种和当地树种青杄进行早期生长评价,研究结果表明:云杉种间的针叶功能性状间存在较大的差异,蓝云杉的针叶的鲜质量、干质量、含水率、针叶长最大;欧洲云杉、白云杉、蓝云杉保存率均超过75%,表现出较强的适应性;9年生树高欧洲云杉白云杉蓝云杉,欧洲云杉的为139.4cm,白云杉的为134.2cm,蓝云杉的为121.0cm,树高生长量均比11年生的青杄的大,说明引种的3个树种在甘肃中部干旱半干旱区(临洮)自然条件相对较差、树种资源匮乏的地区生长快适应性强,是优良的高抗速生用材和生态绿化及观赏树种。     

沙地云杉引种实验

沙地云杉是我国珍稀濒危树种,为了扩大这一树种的造林范围,2003年将其树种从内蒙古克什克腾旗的白音敖包引种到呼和浩特,对其适应性进行了观察。结果表明:沙地云杉在呼和浩特市生长正常,两年高生长达6.73 cm,物候期比原产地提前30d,保存率为35.5%,因此沙地云杉有引种成功的可能性。     

呼伦贝尔沙地引种沙地云杉初报

2007年从内蒙古赤峰引种2年生沙地云杉(Picea mongolica)裸根苗并定植在呼伦贝尔市鄂温克旗中心苗圃。2012年春季,分别在半固定沙地和流动沙地进行造林试验,对沙地云杉成活率、保存率、生长量进行观测。结果表明,沙地云杉在呼伦贝尔沙地生长正常,在半固定、流动沙地上的平均存活率达92.5%,年平均高生长量达12.1cm,保存率达86%以上,初步确定沙地云杉在呼伦贝尔沙地可以进行引种造林。     

4种针叶树种引种试验

樟子松、云杉、侧柏、刺柏４种针叶树种在民勤沙生植物园１０多年的引种试验结果表明：樟子松、云杉、刺柏在该地区生长良好，无病虫害发生。云杉、刺柏树形优美，可作庭园、城市绿化树种。樟子松栽植保存率高，生长速度快，适应性强，可作为防护林营造树种。侧柏生长不良，并有锈病发生。     

西藏鲁朗林区云杉引种研究初报

通过对鲁朗林区采伐迹地引种云杉人工更新的调查结果表明，该林区引种云杉进行迹地更新现阶段生长良好，为适地适树引种造林提供了借鉴。     

章古台引种欧洲针叶树育苗试验初报

在辽宁省章古台经多年引种育苗试验表明，引种苗木特别是1年生苗能否正常越冬，成为引种成败的首要限制因子。就欧洲赤松而言，波兰、爱沙尼亚种源1年生苗的越冬保存率在80％以上，2年生苗生长量与樟子松相仿且均能安全越冬，为适宜种源；在试验过的4个欧洲黑松变种中，Pinus nigra var.austriaca较抗寒，1年生苗木越冬保存率可达96％，2年生苗木全部能安全越冬，是最有希望的变种。挪威云杉苗木不能露地越冬，不宜作造林树种引种，可作为绿化树种试栽。     

挪威云杉木育苗技术

挪威云杉木,又名欧洲云杉,常绿乔木类,松科云杉属,干形通直,树形美观,树冠尖,枝条浓密,针叶鲜绿色,是我国引进树种,原产地广泛分布于欧洲的中部和北部,垂直分布于海拔2000米以下的地区。挪威云杉木喜酸性、微酸性肥沃的土壤,适应性、耐寒性强,能够忍受-30℃以下低温,在我国的辽宁、北京、湖北、甘肃等林区引种种植,生长状况良好。根据对挪威云杉木育苗工作的实践,笔者对挪威云杉木的育苗技术总结如下。     

华北落叶松秋季造林成活率高

华北落叶松秋季造林成活率高王惠洮河林区从１９６７年开始引种华北落叶松，１９７０年造林。根据历年更新造林检查和我们调查研究，华北落叶松幼年期比同龄乡土树种粗枝云杉速生。１５年的华北落叶松高生长竟然是同龄粗枝云杉的３．５倍。但是在姚河林区春季造林成活率较...     

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.