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使用蜜蜂4号飞机喷洒2%噻虫啉微胶囊悬浮剂、0.3%阿维菌素+25%灭幼脲Ⅲ号悬浮剂防治杨树食叶害虫。结果表明:利用2%噻虫啉微胶囊悬浮剂防治第15d后平均虫口减退率达到93.18%。利用0.3%阿维菌素+25%灭幼脲Ⅲ号悬浮剂防治后平均虫口减退率第15d达到87.35%。利用蜜蜂4号小型滑翔飞机防治杨树食叶害虫,具有低空低速安全性能好、机动灵活、使用方便、防治效率高、防治成本低等特点。 相似文献
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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。 相似文献
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噻虫啉防治马尾松毛虫和蜀柏毒蛾的林间试验 总被引：2，自引：0，他引：2
开展了静电喷雾与非静电喷雾48%噻虫啉悬浮剂和2%噻虫啉微胶囊悬浮剂防治马尾松毛虫Dendrolimus punctatus(Walker)和蜀柏毒蛾Parocneria orienta Chao林间试验。试验结果表明:使用相同浓度药液,静电喷雾的防治效果明显优于非静电喷雾的防治效果,药液浓度越低,增效幅度越大;静电喷雾低浓度药液与非静电喷雾高浓度药液能获得同样防治效果,可节省农药30%以上;48%噻虫啉悬浮剂4 000倍液和2%噻虫啉微胶囊悬浮剂2 000倍液可作为静电喷雾防治马尾松毛虫3～4龄幼虫和蜀柏毒蛾4～5龄幼虫的适宜药液浓度。 相似文献
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噻虫啉微胶囊粉剂防治松褐天牛药效试验 总被引：3，自引：0，他引：3
林间喷施不同浓度噻虫啉微胶囊粉剂进行了松褐天牛防治试验。结果表明,噻虫啉微胶囊粉剂对松褐天牛有较强的毒杀效果,且持效期可达35d以上。2%、1%、0.5%噻虫啉微胶囊粉剂在喷施35d后天牛校正死亡率依次为82%、75%和47%。林间喷施0.5%噻虫啉微胶囊粉剂30d内可有效控制松褐天牛种群数量,而1%和2%噻虫啉微胶囊粉剂有效期可持续70d。喷施0.5%、1%和2%噻虫啉粉剂的林区松树死亡率分别为0.15%、0.16%和0.08%,相对防效分别为75%、73.3%和86.7%。因此,建议用1%噻虫啉微胶囊粉剂在林间喷粉防治松褐天牛。 相似文献
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为筛选出防治杨树食叶害虫的高效低毒杀虫剂,降低食叶害虫危害,保障林业的健康可持续发展,试验选取0.5％苦参碱水剂、10％虫螨腈悬浮剂、25％灭幼脲悬浮剂和8％氯氰菊酯悬浮剂4种杀虫剂,在林间条件下,对比分析了4种杀虫剂对杨树食叶害虫的防治效果.结果表明,供试4种杀虫剂对杨树食叶害虫均有一定的防治效果,以0.5％苦参碱水... 相似文献
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6种生物化学农药对刚竹毒蛾幼虫的毒力及防治效果 总被引：4，自引：4，他引：0
为明确3%高渗苯氧威乳油、5%氟虫脲乳油、25%阿维·灭幼脲悬浮剂、20%除虫脲悬浮剂、1.8%阿维菌素乳油和25%灭幼脲三号悬浮剂等农药对刚竹毒蛾幼虫的毒力和林间防治效果,采用点滴法测定出6种药剂的致死中浓度（LC50）等毒力指数,同时开展林间应用防治试验。结果表明：6种生物化学农药对刚竹毒蛾幼虫杀虫活性好,以3%高渗苯氧威乳油的杀虫活性最强,20%除虫脲悬浮剂的杀虫活性较弱;3%高渗苯氧威乳油、5%氟虫脲乳油、25%阿维·灭幼脲悬浮剂、1.8%阿维菌素乳油、25%灭幼脲三号悬浮剂和20%除虫脲悬浮剂LC50分别为1.962、4.573、4.691、4.827、5.051和5.106 mg/L;6种农药的无人机喷雾,药后5 d林间防治效果均达86%以上。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
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. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
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. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
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. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
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. 相似文献
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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。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
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. 相似文献
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Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
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. 相似文献
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A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
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. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):166-178
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. 相似文献