我国松墨天牛研究进展

松墨天牛是一种危害马尾松等林木的虫种，成虫又是松材线虫的主要传播媒介。近些年来，该虫在我国扩散速度很快，造成经济损失严重。本文系统综述了松墨天牛在我国的生物学特性、发生条件、预测预报及防治技术研究进展情况，对该虫今后在生物学、生理学和生态学等方面的研究有一定参考价值，同时对制定该虫综合防治策略和方案也有实用意义。     

松墨天牛成虫羽化逸出及其携带松材线虫能力的研究

松墨天牛成虫是松材线虫病的主要传播媒介,研究其成虫羽化逸出规律及其携带松材线虫能力,在松墨天牛和松材线虫的监测和综合治理上具有重要意义。研究结果表明,松墨天牛成虫羽化逸出期和高峰期,平均每年分别为８３ｄ和１２．３ｄ。携带松材线虫的松墨天牛成虫平均寿命为２９．８ｄ。松墨天牛成虫全身均能携带松材线虫,其数量比率顺序为胸〉头〉腹〉触角〉足〉翅。在浙江省富阳市,林间采用引诱剂诱获的松墨天牛成虫,平均每头携     

松墨天牛生物学特性及防治的研究进展

松墨天牛分布广泛,危害严重,同时其成虫能传播松材线虫,加重了对松树的危害。本文综述了松墨天牛的生物学特性和防治的研究进展,对今后进一步研究松墨天牛的生物学、防治及其它方面提供了一个基础。     

松褐天牛雌雄成虫的判别

松褐天牛Monochamus alternatus Hope是我国松林习见的重要蛀干害虫,也是松材线虫病的媒介昆虫。成虫羽化后,其气管携带大量线虫在成虫取食松树嫩皮时,线虫即经伤口进入树体。因此,成虫期不仅是天牛取食、扩散及生殖活动的重要时期,也是携带、传播松材线虫的关键虫态,是研究和防治松褐天牛及松材线虫病的重要环节。迅速而准确地判别松褐     

松褐天牛性信息素的触角电位和气质联机鉴定

松褐天牛Monochamus alternatus是松树癌症松材线虫病Bursaphelenchus xylophilus的媒介昆虫。利用松墨天牛性信息素可以引诱到未交配,未产卵的松墨天牛,提早诱杀带线虫的松墨天牛,能更有效地减少松材线虫病的传播蔓延和松墨天牛的为害。本文通过性行为学观察、“Y”型嗅觉仪、气相色谱和触角电位（GC-EAD）、气质联机（GC-MS）分析,鉴定出1种雄性信息素壬醛,为进一步研发松褐天牛性信息素引诱剂打下了良好的基础。     

松墨天牛种群动态监测和诱捕器野外应用技术探讨

指出了松墨天牛是松材线虫的主要传播媒介和携带者,随着松墨天牛的取食和产卵,松材线虫会进入到松树中,故当前世界各国不仅充分重视松材线虫的防治,同时还加强对松墨天牛防治的研究,将其作为松材线虫病的一种主要防控措施。基于此,针对松墨天牛种群动态监测和诱捕器野外应用技术进行了探讨。     

黑光灯诱杀松墨天牛成虫防治试验

1997年试装250、400W黑光灯各1盏进行诱杀天牛成虫试验。灯下1晚1灯最多诱杀天半成虫230只,6月上半月能诱杀天牛成虫55％～65％,35D诱虫90％以上;去振松树枝条收集天牛成虫,对照区比灯诱区集虫总数高出11倍;调查松林中松树嫩梢被害情况,对照区比灯诱区松树嫩枝被害率高出8倍;解剖灯诱区天牛成虫90％携带松材线虫,其中含1万头以上占50％。故灯诱松墨天牛可以大量降低松林中松墨天半虫口密度,延缓松林线虫病的扩展。     

温度对松墨天牛传播松材线虫的影响

【目的】研究温度对松墨天牛传播松材线虫的影响,为松材线虫病的预防和防治提供理论与技术支持。【方法】设置3个恒定温度（15、20和25℃）环境,将150只松墨天牛分为3个组（各组50只）,分别在3个恒定温度下饲养,测定不同温度条件下松墨天牛的寿命及松材线虫的存活情况,探讨温度对松墨天牛传播松材线虫的影响。【结果】松墨天牛平均寿命随着温度的降低而降低。3种温度处理对松墨天牛平均寿命的影响存在显著差异,但对初始松材线虫数量无影响。松墨天牛寿命与温度有关,而与体重无关。松墨天牛携带的松材线虫数量在最初的5 d内基本不变,然后随着松墨天牛年龄的增加而减少。当松墨天牛初始携带100～999条松材线虫时,平均传播效率随着环境温度的降低而降低;当线虫初始负荷为1～99时,温度处理对松材线虫平均传播效率的影响不显著。随着温度的降低,松材线虫离开松墨天牛所需的时间增加,松材线虫离开松墨天牛所需的时间在25℃时最短,在15℃时最长。3种温度处理下松材线虫传播效率都呈单峰传递曲线,松材线虫携带量峰值随着温度的降低而降低。【结论】环境温度降低,松墨天牛寿命缩短,线虫传播效率降低,线虫传播高峰期推迟,峰值降低,表...     

松材线虫病的潜伏侵染及松墨天牛传播途径

在南京用松材线虫接种7种松树，于第2a在无任何症状的松树的接种点上方10cm处取样，分离线虫，结果表明松材线虫病的潜伏侵染现象比较普遍，在不同的松树品种上潜伏侵染现象有所差异，感病黑松和赤松很快死亡，只有在接种量小的情况下才有潜伏侵染现象发生，抗病性强的火炬松和湿地松感病后潜伏侵染现象比较普遍，并且样品中的线虫量也较高，而抗病性中等的马尾松和刚松感病后潜伏侵染现象的普遍性及样品中的线虫量均处于中等，短针松接种松材线虫后既不枯死，也无潜伏侵染现象，松墨天牛传播松材线虫的试验结果表明，未携带松材线虫的松墨天牛成虫在松材线虫病松枝上取食后，再到健康松枝上取食，有传播松材线虫的可能，这些结果表明在松材线虫病新病区清理病死木时，应采取早期诊断技术，把未表现症状的松树一起清除，以达到防治目的。     

香港地区松材线虫的初步观察

众所周知,松材线虫(Bursophelenc-hus xylophilus)在香港地区出现并直接或间接地造成马尾松(Pinus masoniana)和湿地松(P. elliottii)的"骤死"症状.松墨天牛(Monochamus alternatus)被认为是该线虫的主要传播媒介.松墨天牛在香港地区的亚热带气候条件下发育非常迅速,1年完成2-3个世代.由松材线虫为害引起的松树枯萎是香港地区近年来导致松树大量损失的主要因素.     

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.