飞机喷洒Bt粉剂防治天然胡杨林春尺蠖技术

应用Y-5B型飞机低量喷洒16 000 IU/mg的Bt可湿性粉剂防治天然胡杨林春尺蠖,用量为1 500 g/hm2和1 200 g/hm2。结果表明两种剂量都具有高效持效的特点,1 200 g/hm2可使虫口减退率达到97%,有效地减轻了春尺蠖对新疆天然胡杨林的危害,防治成本有所下降。     

R44Raven-Ⅱ型直升飞机防治核桃黑斑蚜试验初报

使用罗宾逊R44Raven-Ⅱ型直升飞机静电喷雾1%苦参碱乳油进行了防治核桃黑斑蚜试验,经测定飞行参数的有效喷幅为40m,每架次理论作业面积为53.33hm2,每架次有效作业时间测定401s即6.7min。结果表明:虫口减退率最高为93.25%,防治最终效果为85.87%,达到相关技术要求。通过效益评价,飞机防治核桃黑斑蚜防效好,效率高,比人工防治节约成本270元/hm2,适于在有条件的区域应用。     

应用高空杀虫炮防治森林虫害

2003年,伊春市小兴安岭植物园的535 hm2落叶松人工林实验地大面积发生兴安落叶松鞘蛾(Coleophora dahurica Falk)虫害,据春季调查数据显示,危害较重的林地面积为374 hm2(虫口密度为58头/m枝),危害严重的林地面积为161 hm2(虫口密度为126头/m枝).通过室内药效试验筛选确定无公害药剂森得保可湿性粉剂大白粉1:15进行喷粉防治效果最为理想.防治中使用一些地面常用农药喷洒设备将杀虫剂喷洒到树梢和嫩枝上,但由于树木高大,这些地面常用农药喷洒设备都不能将药剂有效地喷洒到20 m以上高度,难以达到预期的防治效果.     

飞机超低量喷洒Bt、灭幼脲与高效氯氰菊酯混剂防治春尺蠖试验

新疆维吾尔自治区阿克苏地区沙雅县天然胡杨林春尺蠖的危害越来越重,2004年4月在沙雅县应用“Y-5B”飞机超低量喷洒16000国际单位/mgBt 1.5kg/hm2 4.5%高效氯氰菊酯60g/hm2和25%灭幼脲III号3.75kg/hm2 4.5%高效氯氰菊酯60g/hm2防治胡杨林春尺蠖的试验结果表明,两者均具有较好的杀虫效果,虫口减退率分别为95.57%、95.25%。     

飞机喷施森得保可湿性粉剂防治马尾松毛虫试验

采用不同浓度配比Bt 阿维菌素 DPCPV 混合制剂与森得保可湿性粉剂进行飞机喷施防治马尾松毛虫对比试验,施药后1,3,10,30 d 后调查虫口减退率,30 d后各种处理的虫口减退率均在87%以上,无明显差异,但在施药后1～10 d森得保试剂的虫口减退率明显高于常用的Bt 阿维菌素 CPV混合制剂.     

五种药剂及混剂防治大叶黄杨日本龟蜡蚧的效果

日本龟蜡蚧Ceroplastes japonica Green是昆山地区大叶黄杨Euonymus japonicus等植物的主要害虫。选用48%毒死蜱乳油、5%高效氯氰菊酯乳油、10%吡虫啉可湿性粉剂、25%吡蚜酮悬浮剂、2%阿维菌素乳油及混剂进行田间防治日本龟蜡蚧试验。结果表明,吡虫啉可湿性粉剂效果最佳,校正虫口减退率为79.03%,与毒死蜱等体积混合的吡虫啉溶液的校正虫口减退率为72.54%,这2种药剂防治效果显著高于其它药剂处理。     

几种新型生物杀虫剂防治美国白蛾林间药效试验

利用1%苦参碱可溶性液剂、1.2%苦·烟乳油、20%环益微胶囊悬浮剂、森得保可湿性粉剂(0.18%阿维菌素+100亿活芽孢/克苏云金杆菌)、3%苯氧威乳油5种生物制剂农药对美国白蛾Hyphantria cunea(Drury)2~4龄幼虫进行了林间防治试验,以25%灭幼脲Ⅲ号悬浮剂为对照。结果表明,1%苦参碱可溶性液剂1000~1500倍对美国白蛾的防治效果7天均达100%;1.2%苦·烟乳油1000~1500倍防治效果5天均达100%;20%环益微胶囊悬浮剂1000倍液5天后达100%,1500倍7天后达99%以上;森得保可湿性粉剂7天后防治效果达99%以上;3%苯氧威乳油3000~4000倍5天后防治效果达100%。     

沂源县飞机施药防治松阿扁叶蜂技术研究

沂源县运用AS350B3直升机喷洒2%噻虫啉、30%阿维·灭幼脲、1.2%烟碱·苦参碱防治松阿扁叶蜂试验,研究结果表明,三种药物均能取得较好的防治效果。在施药7d后,飞防区样木上松阿扁叶蜂虫口减退率分别为2%噻虫啉96.8%、30%阿维·灭幼脲92.5%、1.2%烟碱·苦参碱95.3%;施药15d后,松阿扁叶蜂虫口减退率分别为为2%噻虫啉97.7%、30%阿维·灭幼脲96.2%、1.2%烟碱·苦参碱96.5%。采用飞机施药灭杀松阿扁叶蜂,用时少,成本低,对环境友好,特别是在地形复杂的山区和发生大面积虫害的区域具有极大的优势。     

美国白蛾飞机防治试验

美国白蛾繁殖能力强、传播快、寄主广、危害严重,而飞机防治具有效率高、效果好、成本低等优点.2012年濮阳市实行大面积、高覆盖的飞机防治第1代美国白蛾,利用飞机喷洒阿维·灭幼脲悬浮剂、烟碱·苦参碱乳油、甲维盐、阿维·杀铃脲等4种不同配方农药试验,表明25％阿维·灭幼脲与1.2％烟碱·苦参碱乳油配比的防治效果最好.飞防效果随施药时间的增长逐步增强,到15d时,虫口减退率可达96.6％;其次为25％阿维·灭幼脲与0.5％甲维盐配比,虫口减退率达到96.0％.     

“空中拖拉机”在复杂山区防治蜀柏毒蛾试验

摘要：本文首次在地形复杂、地势陡峭的四川省梓潼县七曲山国家级森林公园运用AT-504飞机防治蜀柏毒蛾2—3龄幼虫,作业流量2400mL·hm,喷幅80m,平均雾滴密度为15个·cm,雾滴直径140～200μm,喷洒覆盖率达90％以上。结果表明：“空中拖拉机”在复杂山区的喷洒作业质量与在平原地区相比,没有明显差异。喷洒1．2％烟碱·苦参碱乳油和3％苯氧威乳油15天内蜀柏毒蛾虫口减退率达89．5％和88．0％,飞防效果十分显著。“空中拖拉机”不仅适合平原地区农业和林业飞机喷洒作业,而且适合复杂山区林业有害生物的飞防作业,具有效果好,成本低、效率高的优点,可以大面积推广应用。     

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。     

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.