应用蜡状芽孢杆菌防治棉蝗的初步研究

蜡状芽孢杆菌（ＢａｃｉｌｌｕｓｃｅｒｅｕｓＦｒａｎｋｌａｎｄａｎｄＦｒａｎｋｌａｎｄ）是新发现的一种杀虫效率高，杀虫速度快的杀蝗微生物，用４．４×１０６和４．４×１０７孢子／ｍｌ接种棉蝗大龄跳蝻及成虫，棉蝗的死亡率分别达到８２．６％和８０．８％。毒力测定结果ＬＣ５０为２．７×１０８孢子／ｍｌ。林间大面积试验，杀虫效果达７７．９％。     

分离及利用蝗虫霉防治棉蝗的研究

蝗虫霉能在棉蝗种群中自然流行，活体复制的蝗虫霉的接种试验效果可达１００％，林间大面积防治的效果达８５．１％，毒力测定结果Ｌｃ５０为３．４７×１０７孢子／ｍｌ。人工分离培养的蝗虫霉的毒力有所下降。     

苏云金杆菌和白僵菌对云南松毛虫的生物活性测定

将不同的苏云金杆菌菌株Ｂｔ１．Ｂｔ２、Ｂｔ３及白僵菌菌株５ＳＯ３、ＬＳ、ＧＤ，配制成不同浓度的悬浮液，饲喂感染３龄云南松毛虫幼虫。实验结果表明：生物活性较强的菌株有Ｂｔ２及５ＳＯ３，其感染浓度与死亡率值回归方程式为Ｙ（Ｂｔ２）＝－３．８１６２＋１．１６６５ｘ；Ｙ（５ＳＯ３）＝－２．３２７４＋１．００６２ｘ。致死中浓度ＬＯ＿（５０）为３．６１４×１０￣７细菌／ｍｌ和１．９１７×１０￣７孢子／ｍｌ；致死中时间ＬＴ＿（５０）分别为２．６４１天和７．６１９天。     

AciNPV复合杀虫剂的研制及应用的研究

本文重点对ＡｃｉＮＰＶ复合杀虫剂的研制进行了试验应用研究。通过对敌杀死、灭幼脲Ⅲ号、硼酸不同浓度防治试验，筛选出亚致死浓度：２．５％敌杀死为０．００５ｐｐｍ，２５％灭幼脲Ⅲ号为２５ｐｐｍ，硼酸为２００ｐｐｍ。与ＡｃｉＮＰＶ２．５×１０６ＰＩＢ／ｍｌ复合使用，３种化学制剂５种浓度都有增效作用，Ｌｔ５０较单用ＡｃｉＮＰＶ２．５×１０６ＰＩＢ／ｍｌ防治提前１．６７～３．９５天。防治效果：２．５％敌杀死＞２５％灭幼脲＞硼酸；复配药剂费用：硼酸＞２５％灭幼脲＞敌杀死。在研制ＡｃｉＮＰＶ复合杀虫剂或防治时，以２．５％敌杀死０．００５ｐｐｍ、２５％灭幼脲２５ｐｐｍ作为ＡｃｉＮＰＶ复合杀虫剂的复配药剂最佳浓度，成本低、增效作用明显     

枣尺蠖核多角体病毒活性及林间防治试验

本文报道了枣尺蠖（ Ｃｈｉｈｕｏ ｚａｏ Ｙａｎｇ） 核多角体病毒（ＣｚＮＰＶ） 活性的生物测定结果及在山西太谷枣树林间防治枣尺蠖的试验效果。以不同浓度该病毒悬液浸渍鲜枣树叶,饲喂感染３ 龄初枣尺蠖幼虫,病毒浓度对数值与死亡机率的回归直线方程为＾ｙ ＝ ０ ．２３１ ＋ ０ ．８５９ ｘ ;ＬＣ５０ 及９５ ％ 的置信限分别为３－６５ ×１０５ 及４－０４ ×１０４ ～３－１３ ×１０６ＰＩＢｓ／ｍ Ｌ。以２－５ ×１０５ 、１－２５ ×１０６ 、２－５ ×１０６ 、１－２５ ×１０７ 和２－５ ×１０７ＰＩＢｓ／ｍ Ｌ５ 种浓度病毒感染３ 龄初幼虫,其ＬＴ５０ 值分别为１０－０１ 、９－５７、９－０８ 、７－９４ 和７－４９ ｄ 。同一浓度病毒（２－５ ×１０６ ＰＩＢｓ／ｍＬ） 对不同虫龄感染力不同。幼虫死亡率随虫龄增大而降低,从２ 龄的９６－７ ％ 降低到４ 龄的３０－０ ％ ;ＬＴ５０ 值随着虫龄增大而增大,从２ 龄的５－９７ ｄ 增加到４ 龄的１２－５７ ｄ 。在山西太谷枣林枣尺蠖幼虫２ 龄、３ 龄占８５ ％ 时喷洒浓度为２－５ ×１０７ＰＩＢｓ／ ｍＬ 的病毒悬液,虫口减退率高,成本较低,可在生产上推广应用     

对马尾松毛虫敏感的苏云金杆菌菌株筛选试验研究

用对鳞翅目比较敏感的４种苏云金杆菌菌液浸渍马尾松针叶，喂食３—４龄马尾松毛虫幼虫，５天后感染浓度与死亡机率值回归方程为Ｙ１＝１．０６３５＋０．４５１５ｘ，Ｙ２＝－１．４４７０＋０．８１３０ｘ，Ｙ３＝０．２０５９＋０．６１５ｘ，Ｙ４＝３．００２６＋０．１１７９ｘ；半致死中浓度ＬＣ５０值分别为５．２３６８ｘ１０８、８．５１７１ｘ１０７、６．２３７４ｘ１０７和８．７６４８ｘ１０１５ｃｅｌｌ／ｍｌ。以３ｘ１０８ｃｅｌｌ／ｍｌ浓度感染４龄幼虫，其致死中时间ＬＴ５０值分别为５．７４７３、３．５５７２、４．８１７７、１６．０８６２天。结果表明：Ｂｔ（２）菌株对马尾松毛虫毒力次于Ｂｔ（３），但致死中时间最短，可供生产上应用于林间防治。     

55％林丹胶悬液对竹蝗的毒力测定

本文测定了５５％林丹胶悬液对３龄黄脊竹蝗（ＣｅｒａｃｒｉｓＫｉａｎｇｓｕＴｓａｉ）的胃毒毒力和触杀毒力，结果表明：林丹的杀虫作用是胃毒，致死中量ＬＤ５０为４．１８７μｇ／ｇ；用５００×１０－６、１５００×１０－６、３０００×１Ｏ－６、４５００×１０－６的药剂点滴竹蝗头、胸部之间的节间膜，竹蝗死亡率为０－５％。     

蜡蚧轮枝菌防治湿地松粉蚧的研究

应用蜡蚧轮枝菌防治湿地松粉蚧的试验结果，用其２．５×１０７／ｍｌ和１．７×１０７／ｍｌ的孢子液室内防治湿地松粉蚧，校正死亡率分别为８６．７％和６５．９％；林地用其每公顷喷孢量为３３×１０１２和１６．５×１０１２个孢子防治湿地松粉蚧，校正死亡率分别为９２．７％和９９．５％。     

造纸车间主要设备及工艺流程简介

方正林业造纸厂是我国林业系统最大的造纸厂，产品品种为挂面牛皮箱板纸，设计规模为３．４万ｔ／年。造纸车间原料为：以制浆车间来的阔叶材半化学浆为底浆，以针叶材化学浆为面浆。１打浆工段１．１主要设备①ＺＮＷ２１型圆网浓缩机面积５ｍ２；转鼓规格１５００ｍｍ×１０６５ｍｍ；生产能力３～３．５ｔ／ｍ２·ｄ；进浆浓度１％～２％，出浆浓度４％。②ＺＮＷ２３型圆网浓缩机面积１５ｍ２；转鼓规格１５００ｍｍ×３３３０ｍｍ；生产能力３～３．５ｔ／ｍ２·ｄ；进浆浓度１％～２％；出浆浓度４％。③４５０双盘磨ＺＤＰ-１１型，…     

昆虫生长调节剂防治黄脊竹蝗的室内药效试验

５种昆虫生长调节剂防治黄脊竹蝗（Ｃｅｒａｃｒｉｓｋｉａｎｇｓｕ）１～２龄跳蝻的室内药效试验结果表明：灭幼脲３号、卡死克和抑太保对跳蝻的致死作用较大;灭幼脲３号增效粉剂有明显的速效作用     

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。     

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.     

Key Habitats in the Norwegian Production Forest: A Case Study

This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes.