不同杀虫剂防治国槐尺蠖药效试验

通过试验研究了使用50%灭幼脲Ⅲ号胶悬剂和25%溴氰菊酯乳油对国槐尺蠖的防治效果,结果表明:50%灭幼脲Ⅲ号胶悬剂1 500倍和25%溴氰菊酯乳油2 000倍液防治效果最好;国槐尺蠖在北京昌平地区每年发生4代,5月中旬为防治第1代幼虫的最佳时期,6月中旬为防治第2代幼虫最佳时期,第3代后世代交替,可根据虫情在2~3龄幼虫期喷药。     

仿生制剂防治桃小食心虫试验初报

本文利用25%灭幼脲Ⅲ号悬浮剂、25%灭幼脲Ⅳ号悬浮剂、1.8%阿维菌素乳油对桃小食心虫进行了防治试验。分别采用灭幼脲Ⅲ号和灭幼脲Ⅳ号200倍液、300倍液、400倍液、500倍液、600倍液5个处理,喷清水对照;阿维菌素1 500倍液、2 000倍液、2 500倍液、3 000倍液、3 500倍液5个处理,喷清水对照。每个处理5株树,3次重复,根据性诱剂监测,在蛾峰第3 d(6月末至7月初)喷施。结果表明：灭幼脲Ⅲ号500倍液、灭幼脲Ⅳ号500倍液、阿维菌素2 000倍液防治桃小食心虫,致使大量卵不能孵化,林间防治虫果率均降至2.20%以下;考虑经济、效果等因素,林间使用阿维菌素2 000倍液防治桃小食心虫,虫果率较对照平均下降79.16%。     

华北落叶松鞘蛾防治技术的研究

笔者研究了黑光灯、苦参素杀虫剂、药剂(1.8%阿维菌素乳油、1.2%烟参碱、25%灭幼脲)喷雾、0.9%阿维菌素喷烟4种华北落叶松鞘蛾的防治技术。结果认为,黑光灯诱捕对落叶松鞘蛾有一定的防治效果,但作用较为局限。1%苦参素植物杀虫剂对华北落叶松鞘蛾幼虫具有较好的防治效果,1∶1 000的效果最佳。1.8%阿维菌素乳油、1.2%烟参碱和25%灭幼脲喷雾均对华北落叶松鞘蛾具有较好的防治效果,1.8%的阿维菌素乳油效果最明显。0.9%阿维菌素地面喷烟对防治华北落叶松鞘蛾成虫效果较好,选择1.0∶25的配比较经济。     

杨小舟蛾药剂防治试验初报

杨小舟蛾为河南省杨树主要害虫。应用25％灭幼脲Ⅲ号、Bt制剂、3％高效苯氧威Ec、0．9％阿维菌素乳油、10％氯氰菊酯乳油5种药剂，对杨小舟蛾进行了防治试验，其中25％灭幼脲Ⅲ号2500倍液、Bt制剂2000倍液两种药高效、低毒、环保、持效期长，是防治杨树食叶害虫的最佳药剂，建议在防治中推广应用。     

4种药剂对海榄雌瘤斑螟的防治效果差异分析

室内测定了3% 高效氯氰菊酯微囊悬浮剂、1.2% 烟碱· 苦参碱乳油、25% 灭幼脲可湿性粉剂 和 2% 阿维· 苏云菌可湿性粉剂4 种药剂对海榄雌瘤斑螟（Ptyomaxia sp.）1~2 龄幼虫的防治效果。结果 表明,在5 000 倍 ~100 000 倍稀释药剂测定范围内,不同药剂处理之间海榄雌瘤斑螟幼虫死亡百分率均 值差异极显著,防治效果为高效氯氰菊酯＞烟碱 · 苦参碱＞灭幼脲＞阿维 · 苏云菌。喷药防治后第 10 天, 高效氯氰菊酯 5 000 倍液、10 000 倍液、50 000 倍液以及灭幼脲 5 000 倍液的海榄雌瘤斑螟幼虫死亡百分 率为 91.67%~93.33%,烟碱 · 苦参碱 5 000 倍液为 87.50%。3 月下旬至 4 月上旬,高效氯氰菊酯、灭幼脲 和烟碱 · 苦参碱在红树林中防控海榄雌瘤斑螟危害具有应用前景。     

应用1.8%阿维菌素防治美国白蛾试验研究

防治美国白蛾3龄幼虫,用1.8%阿维菌素乳油4000倍、5000倍、6000倍液处理后第3天后防治效果分别达到90%、80%、75%以上,处理后第5天防治效果分别达到100%。与25%灭幼脲Ⅲ号胶悬剂40×10-6液处理相比,第3天、第5天防治效果差异显著,击倒速度明显快于灭幼脲Ⅲ号。     

辽阳市弓长岭地区木撩尺蛾的危害与防治

该文对辽阳弓长岭地区木撩尺蛾的危害进行调查与防治方法试验。结果显示:受灾的林地越冬虫蛹基数较大,死亡率很低,是造成木撩尺蛾暴发的根本原因。物理防治以采取人工挖蛹、灯光诱杀效果较好。药剂防治应用25%灭幼脲Ⅲ号600倍液防治效果可达96.3%,80%敌百虫800倍液的防治效果可达99%,21%通杀乳油1 000倍液的防治效果可达98%,1.2%烟参碱乳油1 000倍液的防治效果可达70%,这几种药剂皆可用于木撩尺蛾的防治。     

四种药剂防治云杉阿扁叶蜂试验研究

云杉阿扁叶蜂（Ａｃａｎｔｈｏｌｙｄａ ｐｉｃｅａｃｏｌａ）是分布于祁连山林区危害青海云杉的主要害虫，蔓延迅速，危害严重。用药品进行防治试验，表明野外用２５％灭幼脲Ⅲ号胶悬剂４０００倍、２．５％功夫乳油１００００倍、８０％敌敌畏乳油８００倍、２．５％敌杀死乳油３０００倍稀释液常量喷雾，２５％灭幼脲Ⅲ号胶悬剂１００倍、２５％灭幼脲Ⅲ号胶悬剂加２．５％功夫乳油（１００＋２０００倍）稀释液超低容量喷雾杀虫     

灭幼脲Ⅲ号防治松毛虫试验

采用1 500～2 000倍液灭幼脲Ⅲ号对松毛虫进行防治试验,结果表明:采用灭幼脲Ⅲ号防治松毛虫,地面杀虫效果可达90%,对松毛虫的幼虫、蛹、成虫、卵有连续的灭杀作用,成效显著,而且灭幼脲Ⅲ号胶悬剂易形成胶膜而不易被水冲刷,残效期较长,成本低,经济有效。     

云杉腮扁叶蜂药剂防治试验

本文应用化学药剂对云杉腮扁叶蜂进行了防治试验.结果表明:利用1.2％烟碱·苦参碱乳油300倍液防治云杉腮扁叶蜂成虫,防治效果为28.57％;利用25％灭幼脲Ⅲ号悬浮剂1000倍液的防治效果为62.24％;利用4.5％高效氯氰菊酯微乳剂1000倍液防治效果达82.65％;利用弥雾机按高效氯氰菊酯、柴油、水的体积比为1:2...     

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.