新型木材防腐剂的研究

本研究通过对国内外现有木材防腐剂的筛选和改良,得到了两个比较理想的配方ACB(暂定名)和CCB-M,并测定了它们的抗腐力、抗流失性、防蚁、防霉和防变色性能、耐燃性、对动物毒性、对木材强度的影响、对金属的腐蚀性等各项指标。ACB适合于橡胶木和建筑材的防腐,CCB-M可用于对处理材颜色要求不高的场合。是有推广价值的木材防腐剂。     

铜防腐剂及百菌清处理3种木材的野外耐久性能

在广东亚热带气候条件下,不同剂型的季铵铜(ACQ)、柠檬酸铜(CC)、百菌清(CTL)及铜铬砷(CCA)处理马尾松、湿地松、毛白杨后的野外埋地耐久性能的结果表明:毛白杨防腐处理后不宜在与地接触的条件使用,可以用于快速初步评价防腐剂的野外耐久性能;吸药量6.4～8.5 kg/m3时,CTL处理后的木材不宜在与地接触的条件下使用;湿地松的ACQ-B 及 CC防腐、防白蚁效果相当;对于马尾松、湿地松,吸药量6.0～6.8 kg/m3 时,ACQ-B、CC处理的试材埋地6年后,防腐效果较好,防白蚁的效果尚可;对于马尾松、湿地松,吸药量约10 kg/m3时,ACQ-B、CC、CCA处理的试材埋地6年后,防腐、防白蚁效果较好.     

樟子松热处理材耐久性能的评价

对樟子松热处理材进行室内防霉、防蚁蛀及野外埋地检测,综合评价其耐久性能。结果表明:樟子松热处理材对霉菌、变色菌均无防治效力,不抗白蚁蛀蚀;樟子松热处理材的耐久年限约为3年。     

戊唑醇和丙环唑的耐腐性能评价

分析评估了以戊唑醇(TEB)和丙环唑(PPZ)为主要活性成分防腐剂的耐腐性能.结果表明,TEB或PPZ载药量达到240 g/m3时,能有效地防止腐朽菌对木材的侵害;TEB和PPZ的耐腐性能无明显差异;复配防腐剂的使用效果优于单独使用TEB或PPZ.野外埋地试验结果表明,TEB加入溴氰菊酯后,处理材可达到理想的防白蚁效果...     

化学改性杨木的抗白蚁和抗霉耐腐性能研究

抗蚁蛀、耐腐性测定结果表明:工厂用化学改性药剂LM-1处理生产的杨木,其抗霉、抗菌变色和耐腐性能大为增强;室内抗白蚁能力提高4个等级,试验白蚁存活期仅7～9d,比对照缩短21～61d;野外抗蚁和耐腐性完好指数达10,大幅提高了野外耐久性。     

壳聚糖金属配合物处理后竹材的防白腐性能

以4年生新伐毛竹为试材,以白腐菌彩绒革盖菌为试菌,对壳聚糖铜配合物(CCC)、壳聚糖锌配合物(CZC)及相应的金属盐(氯化锌)和铜铬硼(CCB)处理材的抗流失性和耐腐性能进行试验.结果表明: 壳聚糖金属配合物在竹材中固着率略高于CCB,明显高于相应的金属盐,具有较强的抗流失性能;CCC处理的竹材对彩绒革盖菌的耐腐性能高于CCB处理材, 当CCC处理材中金属离子保持量达到6.35 kg·m-3时,腐朽后质量损失为0;CZC处理毛竹试材的耐腐效果和CCC效果相当,明显高于氯化锌处理材,当防腐剂中金属离子保持量高于2.41 kg·m-3时,CZC处理的竹材都达到最耐腐等级,且随着防腐剂中金属离子保持量的提高,处理材的质量损失率接近于0.     

白捕特微胶囊防治白蚁药效试验

1997—2003年在浙江余杭开展白捕特微胶囊防治白蚁试验,5种药剂质量浓度(62 5,125,250,500,1000mg·kg-1)的触杀作用试验结果均达100%,最低质量浓度62 5mg·kg-13d后的死亡率也达到100%;驱避效应、木块抗蚁效果理想,只有经低质量浓度(62 5mg·kg-1)处理过的土壤,白蚁才能穿越一定距离。野外土壤处理试验,经250～1000mg·kg-1药剂质量浓度处理过的土壤对白蚁的防治效果与药液浓度呈正相关趋势,其中1000mg·kg-1浓度组,经过5a的防蚁效果仍达100%,6a后的防蚁效果达80%,同时,经风化处理后对其药效影响不明显。白捕特微胶囊对于黄胸散白蚁比家白蚁效果更好。     

几种防腐剂处理的马尾松材室内抗家白蚁(Coptotermes formosanus Shiraki)效果试验

利用三种防腐剂处理后的马尾松（Pinus massoniana Lamb．）边材在室内接种家白蚁（Coptotermes formosanus Shiraki）以测试其抗蚁蛀能力。这三种防腐剂包括含砷铬类防腐剂铜铬砷（CCA）和两种非含砷铬类防腐剂柠檬酸铜（CC）、季铵铜（ACQ）。测试一个月后的结果表明,三种防腐剂的各个测试浓度的抗蚁蛀效果很好,试块的失重均不超过5％。经方差分析及平均数多重比较结果表明,三种防腐剂不同处理浓度与对照间试块的实际失重的差异以及白蚁存活率的差异均达显著水平（P〈0．05）。CCA防腐剂在0．05％～1．00％浓度（实际吸药量0．60～6．07kg／m^3）处理下,白蚁全部死亡,试块表面被轻度蛀食。CC与ACQ防腐剂的抗蚁蛀效果很相似,在0．6％～2．0％高浓度（实际吸药量分别为3．94～12．90kg／m^3和3．04—9．92kg／m^3）下,白蚁全部死亡,试块未被白蚁蛀食,完好无损;但在0．2％～0．4％低浓度（实际吸药量〈3kg／m^3）下有部分白蚁存活,试块被白蚁轻度或中度蛀食;低浓度组与高浓度组之间白蚁存活率的差异达显著或极显著水平。从白蚁存活率、试块的失重及试块抗蚁蛀等级综合分析结果表明,经CCA、CC、ACQ三种防腐剂处理后的马尾松木材的抗蚁蛀能力明显提高。     

纳米氧化铜木材防腐剂的防腐性能和抗流失性研究

以大青杨为试材,进行室内木材防腐试验和实验室水流失试验,研究纳米氧化铜木材防腐剂效果和抗流失性能.研究结果表明:经过纳米氧化铜防腐剂处理后,大青杨试样耐腐能力大大提高,失重率明显减少,当药剂浓度为1.6％时已经达到强耐腐等级.该防腐剂的耐褐腐能力与耐白腐能力相比稍差.不同浓度防腐剂处理后,大青杨试样中防腐剂的保持量随防腐剂浓度的增加而增加.另外,纳米氧化铜防腐剂具有很好的抗流失性能.     

房屋建筑材（木窗）防腐处理应用性试验（初报）：药剂和处理方法

建筑材(木窗)防腐处理应用性试验表明:防腐剂PPA,CCB和CCA_(S)可用于门窗材的防腐处理。PPA宜采用双真空法;CCA_(S)、CCB宜采用加压法。其吸药量宜控制在窗框6kg/m~3,扇窗4kg/m~3。处理前应先机械加工,按窗框和窗扇分类进行防腐处理。对于难处理树种木材应考虑密封堆集扩散作业,使用水溶性防腐剂(CCA_(S)、CCB)时需采取木材防变形措施。     

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.