1,1—二甲基—7—异丙基—1,2,3,4—四氢萘—6—磺酸钠的合成

文章探讨了１，１－二甲基－７－异丙基－１，２，３，４－四氢萘－６－磺酸钠合成的磺化工艺。通过实验室的试验，确定了适宜的工艺条件，１，１－二甲基－７－惜内基－１，２，３，４，－四四氢萘与浓度硫酸的配比为１：１０．５（ｍｏｌ比），反应温度９０±２℃，反应时间２０ｍｉｎ，产品得率达８０．３％。同时测定了产物表面活性性能，可用作表面活性剂。     

河北西陵地区混交林的调查研究

通过对侧柏－油松，加杨－油松和毛白杨－刺槐三种混交类型地上部分和地下部分进行调查发现，侧柏－油松混交和毛白杨－刺槐混合效果很好，可在生产中推广，加杨－油松混交效果不好，不宜在生产应用。     

淹水胁迫对杨树无性系苗期生长及生理的影响

本实验是利用花坛扦插的方法，对３个无性系：ＮＬ－８０１０５杨，１－６９杨，ＮＬ－８０３５１杨的苗期进行人工淹水处理，处理包括：Ａ－对照，Ｂ－渍， Ｃ－涝。在对３种无性系进行各淹水处理的条件，通过定期的观测和采样，测定３个性无系在不同处理条件下，其生长，生理指标的变化情况。     

杨树抗云斑天牛新品种引种试验

杨树抗云斑天牛系列新品种是中国林科院林研所通过杂交和选择培育出来的良种。经５年生和２年生引种试验林数据分析结果表明：不同无性系间在树高和胸径两性状上存在显著差异，树高的广义遗传力高于胸径的广义遗传力，胸径的变异系数高于树高的变异系数，胸径的遗传变异较大（变异系数大于１０％），抗云斑天牛系列新品种（３４－１７，３４－１３５，３４－３１４，３４－３０１，３４－２８６，３４－２９７和３７－３３）生长优于当地主栽品种Ⅰ－６９杨，３４－１８８杨的生长接近Ⅰ－６９杨。     

三个典型林分光照强度的分布规律研究

通过对三个典型林分的林内光照特性及其分布规律的探讨，发现三个林分的透光度：马尾松、枫香－Ｊｉ木－淡竹叶林分〉枫香、杜英－乌药－淡竹叶林分〉闽楠－杜鹃－沙草林分；林荫光照强度水平分布由林荫边向１／２林荫处、林缘、林中逐步递减。通过模拟显示，林地表面的光照强度与林外对比点的光照强度成显著的一元幂函数关系。     

去氢枞酸合成两性表面活性剂及其性质

从歧化松香中分离出去氢枞酸，并以此为原料合成了三种新型的两性表面活性剂，Ｎ－（３－去氢枞酰氧－２－羟）丙基－Ｎ－甲基氨基乙酸钠，Ｎ－｛Ｎ＇－［（３－去氢枞酰氧－２－羟）丙基］胺乙基｝氨基乙酸钠。Ｎ－｛Ｎ＇－［（３－去氢枞酰氧－２－羟）丙基］双胺乙基｝氨基乙酸钠。其结构通过波谱和元素分析得以证实，并测定了其表面物理化学性质如克拉夫特点，临界胶束浓度和分子横断面积。此外还根据相分离模型计算得出胶束化过     

四种片林结构模式的能流物流分析

通过对郁闭后的北京杨片林进行人工强化配置，建立了林－菇、林－羊和林－菇－蚓－鸡结构。以片林结构为对照，采用综合指数法对４种结构的能流、物流、经济生态效益进行了综合定量分析。结果表明，３种人工强化配置的片林结构，能显著提高平原片林的总体效益。尤其是林－茹－蚓－鸡结构，在科学用能，高效利用时间、空间和直接经济效益等方面，具明显优势。     

云南松纵坑切梢小蠹聚集信息素研究

通过对云南松纵坑切梢小蠹聚集信息素的研究，证实该虫种的雌雄成虫均能释放聚集同类的信息素，用气相色谱和质谱色谱仪进行性定量分析，从雌雄成虫后肠和虫粪提取物中分析出聚集信息的主要成分是氧化单萜烯醇：反式－马鞭草烯醇、桃金娘烯醇，Δ＾３－皆烯－１０－醇和马鞭草烯酮，另外，嘛松枝韧皮中分析出对松纵坑切梢小蠹具有强烈吸收力的碳氢单萜烯：α－蒎烯和Δ＾３－蒈烯。通过对聚集信息素单组分及混合剂进行室内和林间生物     

胶南市沙质海岸灌草带植物群落分布及特性的研究

胶南市沙质海昌带植物种为比较丰富，有草本植物１５科２４种，灌木４科４种。通过调查分析，灌草带植物群落有５种，分别是：单叶蔓荆－筛草－肾叶打碗花群落、毛鸭嘴草－筛草－石沙参群落、紫穗槐－白茅－肾叶打碗花群落、柽柳－芦苇－二色补血草群落、芦苇－白茅－刺沙蓬群落，这些群落适应性强，稳定性高，覆盖度和生物量大，是进行群落构建的优选模式。了解５种植物群落适生的立地条件，为沙质海岸不同立地条件植物群落的优选提     

杨树抗云斑天牛新品种引种试验

杨树抗云斑天牛系列新品种是中国林科院林研所通过杂交和选择培育出来的良种。经５年生和２年生引种试验林数据分析结果表明：不同无性系间在树高和胸径两性状上存在显著差异，树高的广义遗传力高于胸径的广义遗传力，胸径的变异系数高于树高的变异系数，胸径的遗传变异较大（变异系数大于１０％），抗云斑天牛系列新品种（３４－１７，３４－１３５，３４－３１４，３４－３０１，３４－２８６，３４－２９７和３７－３３）生长优于     

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.