长鞘卷叶甲化学防治试验

选用7种化学杀虫剂对长鞘卷叶甲成虫进行室内毒力测定,筛选出50%甲好清乳油、40%乐果乳油和90%杀虫单可溶性粉剂等3种杀虫剂的毒力较好,并应用于林间对成虫的防治试验。试验结果表明,分别使用甲好清和乐果的800~1300倍液以及杀虫单的800倍液进行喷雾防治效果较好,用乐果和杀虫单的100倍液进行根灌防治效果较好,用甲好清和乐果的10倍液进行注干防治效果较好,可适当应用于林间防治。     

几种生物农药对茶梢蛾的毒力测定及林间防治试验

为了筛选出最适合防治茶梢蛾的农药,选用6种生物农药和1种化学农药对茶梢蛾幼虫的毒杀力进行了室内测定,并用筛选出的20%乐果乳油、2%阿维.苏可湿性粉剂和3%阿维.氟铃脲乳油这3种毒力较强的农药进行了林间幼虫防治试验。结果表明:使用阿维.苏、阿维.氟铃脲和乐果的2 000倍液进行喷雾防治的效果较为理想,可达到74%～84%的杀虫效果;而用阿维.苏、阿维.氟铃脲和乐果以注干施药法进行防治的杀虫效果并不明显。     

5种植物源杀虫剂对淡竹毒蛾幼虫的毒力及林间防治效果

为筛选出有效控制淡竹毒蛾幼虫的药剂,以制定无公害防治淡竹毒蛾决策,2017年在福建省沙县选用5种植物源杀虫剂,对危害方竹林的淡竹毒蛾幼虫进行室内毒力测定和开展林间防治试验。室内毒力测定结果表明：1%苦皮藤素可溶液、4%鱼藤酮乳油、0.5%藜芦碱可溶性液、1.2%烟碱·苦参碱可溶液、1.5%苦参碱可溶液对淡竹毒蛾幼虫的LC₅₀分别为0.973、1.062、1.216、0.482、0.836 mg/L,以1.2%烟碱·苦参碱可溶液剂对淡竹毒蛾幼虫毒性最强,5种不同植物源杀虫剂对淡竹毒蛾幼虫均有杀虫作用。林间防治效果表明：药后3 d,5种植物源杀虫剂的防治效果均为90%以上,以苦参碱类药剂防治效果最好,2种苦参碱类药剂的林间最佳使用浓度均为1 500倍液;1%苦皮藤素可溶液和0.5%藜芦碱可溶性液林间最佳使用浓度为1 000倍液;4%鱼藤酮乳油林间防治最佳使用浓度为1 200倍液。测试的5种不同植物源杀虫剂均对淡竹毒蛾幼虫有良好的杀虫作用,是无公害防治淡竹毒蛾幼虫的有效药剂。     

黄野螟防治药剂筛选试验

利用浸渍法在室内测定了10种和4种农药分别毒杀黄野螟高龄和低龄幼虫的药效试验,结果表明:对高龄幼虫,1.8%阿维菌素乳油500万倍液,0.5%甲维盐微乳剂500万倍液,森得保可湿性粉剂800倍液,2.5%多杀菌素悬浮剂5 000倍液,90%敌百虫晶体20 000倍液,15%茚虫威悬浮剂3 000倍液和4.5%高效氯氰菊酯乳油1000倍液的致死率均达100%;对低龄幼虫,4.5%高效氯氰菊酯乳油4 000倍液和森得保可湿性粉剂1 000倍液的致死率分别为100%和97.7%。在林间,阿维菌素或甲维盐500万倍液、森得保1 000倍液的杀虫效果均达100%。     

几种药剂对银杏大蚕蛾的毒力测定和防效对比试验

对几种药剂防治银杏大蚕蛾Dictyoploca japonica Butler 2龄幼虫进行了室内毒力测定、林间小区防治试验.室内毒力测定结果表明1.2％烟碱·苦参碱乳油对银杏大蚕蛾2龄幼虫毒力最强,其次为1.8％阿维菌素乳油,最弱的为4.5％高效氯氰菊酯.林间小区防效试验的3种药剂对银杏大蚕蛾2龄幼虫均有很好的防治效果,1.2％烟碱·苦参碱112.5 g/hm2,20％杀铃脲56 g/hm2,25％灭幼脲150 g/hm2为最佳剂量,防效为90.7％ ～92.1％.1.2％烟碱·苦参碱乳油杀虫速率高峰期在第1天;2种仿生物制剂击倒速率较慢,高峰期出现在第10天.1.2％烟碱·苦参碱防治费用最低.     

打孔注药法防治香樟齿喙象幼虫防效试验

香樟齿喙象Pagiophloeus tsushimanus是上海地区危害香樟Cinnamomum camphora的主要害虫之一,该虫主要以幼虫钻蛀香樟主干为害,而传统喷雾防治方法对幼虫防治效果不佳,本文选用打孔注药法针对香樟齿喙象幼虫开展防治,选择10%甲维吡虫啉可溶液剂、1.8%阿维菌素乳油和4.5%高效氯氰菊酯乳油3种农药,每种农药分别配比为原液、5倍、10倍3个浓度梯度,对受害香樟树进行注干防治,针对各处理组连续统计8周防效,通过试验了解不同农药不同浓度对香樟齿喙象的防治效果。试验结果显示防治后8周,10%甲维吡虫啉可溶液剂原液防治效果最好,为77.27%;防效最差为4.5%高效氯氰菊酯乳油10倍液,为46%。     

黄刺蛾的防治技术研究

为了有效控制黄刺蛾(Cnidocampa flavescens Walker)的为害,用10%杀虫葳、40%氧化乐果、4.5%高效氯氰菊酯、25%灭幼脲和1.8%阿维菌素等5种药剂的不同浓度对黄刺蛾进行室内毒力测定和圃间防治试验,并对结果作方差分析。室内外试验结果表明:所选用的5种药剂和浓度对防治效果均有显著影响;林间防治以10%杀虫葳4000倍液喷雾效果最佳,杀虫效果达90%以上。     

缀叶丛螟危害南酸枣的发生规律及防治措施

对缀叶丛螟的形态特征、生活史、生活习性进行观察,并采取室内及林间防治这2种试验方法研究防治措施。结果表明：室内试验选用10％天王星1000倍、90％杀虫单1000倍、20％杀灭菊酯1000倍液效果较好;林间防治应在第1代、第2代幼虫盛发期选用20％杀灭菊酯2000倍、10％天王星2000倍、90％杀虫单1000倍,对3～4龄幼虫进行防治,效果达91％以上,可在大面积爆发时防治应用．     

5种植物源农药防治松丽毒蛾的效果分析

为研究植物源农药及浓度对松丽毒蛾的林间防治效果,于2019年在福建省沙县官庄国有林场的马尾松林分设立试验区,选用0. 6%印楝素乳油等5种植物源农药开展林间喷雾防治松丽毒蛾幼虫试验。结果表明:药后4 d,5种药剂对松丽毒蛾幼虫表现出较好的杀虫效果,0. 6%印楝素乳油、4%鱼藤酮乳油、1%苦参·藜芦碱可溶液、1. 3%苦参碱可溶液和1. 2%烟碱·苦参碱乳油对幼虫的平均死亡率依次为91. 1%、91. 3%、91. 7%、92. 0%和92. 6%,其最适浓度分别为0. 6%印楝素乳油和4%鱼藤酮乳油1000倍液,1%苦参·藜芦碱可溶液1100倍液,1. 2%烟碱·苦参碱乳油和1. 3%苦参碱可溶液1300倍液,在生产防治上可推广应用。     

6种植物源农药防治波纹杂毛虫林间药效分析

为明确6种植物源农药防治波纹杂毛虫的最佳林间配比度和用药量,掌握低空施药技术,在福建省沙县马尾松林建立试验区,开展林间喷雾和喷烟防治试验。结果表明:6种农药的林间喷雾,药后4 d,防治效果均超过90%;最佳林间配比度为:1.3%苦参碱可溶液剂和1.2%烟碱·苦参碱乳油均为1300倍液;1%苦参·藜芦碱可溶液、4%鱼藤酮乳油和0.6%印楝素乳油均为1000倍液,0.5%藜芦碱可溶液为800倍液。2种农药喷烟后3 d,防治效果均超过90%,1.3%苦参碱可溶液和1.2%烟碱·苦参碱乳油与烟雾剂最佳配比度均为1∶9。参试的6种植物源农药可广泛应用于防治波纹杂毛虫幼虫。     

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.