国槐叶小蛾幼虫化学防治试验研究

该文研究了3种化学药剂不同施药剂量对国槐叶小蛾幼虫的防治效果。结果表明:试验使用的3种化学药剂中,50%杀螟松乳油以1000倍液处理校正死亡率最高,50%马拉硫磷乳油1500倍液处理校正死亡率最高,40%乙酰甲胺磷乳油以1500倍液处理校正死亡率最高。根据研究结果,生产上推荐50%杀螟松乳油1000倍液、50%马拉硫磷乳油和40%乙酰甲胺磷乳油1500倍液防治国槐叶小蛾幼虫。     

3种药剂防治核桃举肢蛾效果研究

为筛选防治核桃举肢蛾效果较好的杀虫剂,该试验选用毒死蜱、乙酰甲胺磷和杀灭菊酯3种杀虫剂对核桃举肢蛾进行试验。结果表明:试验选用的3种杀虫剂不同剂量处理对核桃举肢蛾均有一定的防治效果,其中40%乙酰甲胺磷乳油以1000倍液处理对核桃举肢蛾表现出了最高的防治效果,为92.11%;48%毒死蜱乳油1000倍液处理对核桃举肢蛾的效果次之,为85.35%;20%杀灭菊酯乳油以1500倍液处理的防治效果最低为76.27%。3种试验药剂中40%乙酰甲胺磷乳油和48%毒死蜱乳油以1000倍液处理对核桃举肢蛾的防治效果较好,适合在生产中推广应用。     

三种药剂防治核桃举肢蛾效果研究

为筛选防治核桃举肢蛾效果较好的杀虫剂,本试验选用毒死蜱、乙酰甲胺磷和杀灭菊酯3种杀虫剂对核桃举肢蛾进行试验。试验结果表明,试验选用的3种杀虫剂不同剂量处理对核桃举肢蛾均有一定的防治效果。其中,40%乙酰甲胺磷乳油以1000倍液处理对核桃举肢蛾表现出了最高的防效,为92.11%;48%毒死蜱乳油以1000倍液处理对核桃举肢蛾的防效次之,为85.35%;20%杀灭菊酯乳油以1500倍液处理的防治效果最低,为76.27%。3种试验药剂中40%乙酰甲胺磷乳油和48%毒死蜱乳油以1000倍液处理对核桃举肢蛾的防效较好,可以在生产中推广应用。     

树干注药对天然胡杨林蔡氏胡杨个木虱的防控效果

为精准有效防控额济纳旗胡杨林区蔡氏胡杨个木虱的发生,通过田间树干注药试验,研究了15%的乙酰甲胺磷注剂和12%的阿维菌素注剂2种药剂对胡杨林区蔡氏胡杨个木虱的防控效果。结果表明：2种注干药剂对蔡氏胡杨个木虱均有一定的防控作用,并且持续时间长。施药后的10、20、30、40 d,通过观察危害的叶片得出15%的乙酰甲胺磷注剂对于蔡氏胡杨个木虱的防治效果均较12%的阿维菌素注剂防治效果好;2种注干药剂在施药30d后防治效果达到最好。同时由于胡杨林区木虱与网蝽混合发生,在胡杨林区防效调查过程中通过观察发现树干注药对胡杨林区的网蝽也具有较好的控制效果。     

桉树林油桐尺蠖防治试验

为有效控制桉树林油桐尺蠖的危害,选择苏云金杆菌、25%灭幼脲和烟雾剂(4.5%高效氯氰菊酯+30%乙酰甲胺磷+柴油)3种药剂对油桐尺蠖进行防治试验。结果表明:3种药剂对桉树林油桐尺蠖均具有较好的防治作用,第1次施药后第5天,对照虫口减退率仅为1.34%,3种药剂防治的校正虫口减退率均达到65.38%以上。烟雾剂防治油桐尺蠖施药后第5天就可达到虫口减退峰值,连续防治2代,虫口密度减退到0.6头/枝,校正虫口减退率达到97.25%。     

噻虫啉、乙酰甲胺磷防治荔蝽若虫试验

为充分了解乙酰甲胺磷、噻虫啉对荔蝽Tessaratoma papillosa若虫的防治效果,以选择最佳使用浓度,作者选用噻虫啉、乙酰甲胺磷对荔蝽若虫进行了防治试验,结果表明：低浓度的噻虫啉、乙酰甲胺磷亦可杀死荔蝽若虫,乙酰甲胺磷500～1500倍、噻虫啉2000～4000倍防治效果较为理想,校正死亡率分别达到88．37％和91．82％以上。     

印楝素制剂防治松毛虫及松小蠹室内试验初报

应用印楝素乳油进行了松毛虫、松小蠹的室内防治效果试验。试验结果表明用 0 3%印楝素乳油 4 0 0倍“触杀 +胃毒”处理松毛虫 ,施药后 2 0天 ,防治效果达到 88 5 % ;用 0 3%印楝素乳油 10 0倍“触杀 +胃毒 +内吸”处理松小蠹 ,施药后 15天 ,防治效果达到 95 6 %。观察发现 ,施用印楝素后 ,使松毛虫 2龄幼虫产生较强的拒食作用 ,并能抑制其生理发育。     

日本鞘瘿蚊的化学防治技术研究

通过6种药剂的室内外药效试验,结果表明(1)40%的乙酰甲胺磷乳油、30%久效磷乳油1 000倍液用于日本鞘瘿蚊卵孵化盛末期常量喷雾,防治区当年新梢虫害指数减退率都在83%以上,对照区则上升了14.5%.(2)树干注药更适合于高价值林分及虫源地的防治;7月份幼虫危害盛期用30%久效磷乳油插管注药效果最佳,用药量为1.2ml/cm胸径,防治后,虫瘿内幼虫校正死亡率在90%以上,比对照提高了82.3%,树干注药不影响木材的材质.(3)3%米乐尔颗粒剂和3%呋喃丹颗粒剂用于根区施药也具良好的效果.     

4种杀虫剂对悬铃木方翅网蝽的杀卵效果初报

室内采用浸渍法测定了30%乙酰甲胺磷乳油、20%高氯·噻嗪酮乳油、240g/L螺螨酯悬浮剂和4.2%高氯·甲维盐乳油等4种杀虫剂对悬铃木方翅网蝽的杀卵效果。结果表明稀释浓度在900×以上的高氯·噻嗪酮和高氯·甲维盐对悬铃木方翅网蝽卵的防治效果均在80%以上,但高氯·噻嗪酮的防治药剂成本是高氯·甲维盐的3倍以上。各浓度处理的螺螨酯和乙酰甲胺磷的对卵的防治效果都很差,卵的孵化率均在70%以上。20%高氯·噻嗪酮乳油和4.2%高氯·甲维盐乳油对悬铃木方翅网蝽卵的孵化有抑制作用,在田间杀卵药剂选择中可参考使用。     

四种杀虫剂田间防治松沫蝉若虫试验

2016年4月在辽宁章古台通过注药和喷雾方式比较4种药剂田间防治松沫蝉Aphrophoridae flavipes若虫效果。结果表明:注射3.5%高效氯氰菊酯乳油对若虫的防治效果最好,施药21 d后校正死亡率88.52%;喷洒3.5%高效氯氰菊酯乳油1 000倍液对若虫的防治效果最好,施药7 d后校正死亡率91.29%。     

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.