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温室野蛞蝓的发生规律及综合治理技术的研究 总被引：1，自引：0，他引：1
本文介绍了温室有害软体动物野蛞蝓ＡｇｒｉｏｌｉｍａｘａｇｒｅｓｔｉｓＬ．的习性和危害特点，进行了综合防治试验。结果证明，填实育苗营养袋间的空隙防治效果达８９％；地面撒布呋喃丹３％颗粒剂，施用量８．３ｇ／ｍ＾２防治效果达８０％～９５％，方法可行，利于推广。 相似文献
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板栗大圆筒象ＭａｃｏｃｏｒｙｎｕｓＰｓｉｔｔａｃｉｎｕｓ（Ｒｅｄｔ）以成虫危害板栗叶片、严重时栗叶损失达８０％以上，减产２０％－４０％，该虫在皖南一年发生１代，以幼虫在栗林表土层中越冬。采用５０％甲胺磷乳剂，４０％氧化乐果乳剂２０００倍液喷雾，防治效果分别为９１．０１％和９６．２０％，用３％呋喃丹颗粒剂防治幼虫效果为６３．８６％。 相似文献
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该研究应用白僵菌粉剂与０．４％氰戊菊酯粉剂按４∶１比例混合均匀后，加工成粉炮防治马尾松毛虫ＤｅｎｄｒｏｌｉｍｕｓｐｕｎｃｔａｔｕｓＷａｌｋｅｒ，每ｈｍ２放粉炮３０个，每个炮重１２５ｇ，经室内和林间试验以及大面积推广防治，平均防治效果达９０％以上，较纯菌粉粉炮防治有明显的增效作用，平均防效提高１５．３％，害虫感病流行时间提前７天以上；较采用纯０．４％氰戊菊酯粉粉炮防治效果提高２８．８％，能及时有效地控制高虫口林分松毛虫的严重危害，减少松针损失４０％以上，经济效益和生态效益显著 相似文献
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德昌松毛虫质型多角体病毒防治大柏毛虫应用研究 总被引：1，自引：0，他引：1
应用德昌松毛虫质型多角体病毒Ｄｅｎｄｒｏｌｉｍｕｓ ｐｕｎｃｔａｕｓ ｔｅｃｈａｎｇｅｎｓｉｓ Ｃｙｔｏｐｌａｓｍｉｃ ＰｏｌｙｈｅｄｒｏｓｉｓＶｉｒｕｓ防治四川内地柏木林区大柏毛虫Ｄ．ｈｏｕｉＬａｊｏｎｑｕｉｅｒｅ的试验表明,以７．５×１０＾９ＰＩＢ／６６６．６ｍ＾２以上剂量防治３龄幼虫,其综合防效达８５％以上,且具有显著的扩散流行和持续防治效果 相似文献
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化学农药对卵孢白僵菌Ｂｅａｕｖｅｒｉａｂｒｏｎｇｎｉａｒｔｉ菌丝生长、孢子萌发的影响及对蛴螬毒杀剂量筛选的研究试验表明，６０％３９１１、５０％辛硫磷和对硫磷乳油使用浓度＞５０ｐｐｍ时，白僵菌的菌丝生长和孢子萌发受到明显的抑制。２％林丹颗粒剂使用浓度＜１００００ｐｐｍ对白僵菌无明显影响。３．５％的３９１１颗粒剂同白僵菌在苗床上分层施用，防治淡翅黎丽金龟ＢｌｉｔｏｐｅｒｔｈａｐａｌｉｄｉｐｅｎｎｉｓＲｅｉｔｅｒ幼虫，效果达９８．６％，比单独使用３９１１防治效果提高１８．６％。 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(2):131-138
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. 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