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[目的]为明确云南省切梢小蠹种群结构及变化规律,指导切梢小蠹的防控。[方法]在云南蠹害林区调查采样并鉴定切梢小蠹种类,比较20世纪90年代和2010年代石林、安宁、丘北3地切梢小蠹种群结构及变化情况。[结果]共有4种切梢小蠹在云南发生危害,其中,横坑切梢小蠹占发生总量的38.1%,云南切梢小蠹占36.6%,松芽小蠹占19.7%,华山松切梢小蠹占5.6%。小蠹种群结构90年代与目前比较发生了显著变化,主要体现在横坑切梢小蠹和云南切梢小蠹,云南切梢小蠹所占种群数量由20世纪90年代的92.1%减少到目前的42.7%,而横坑切梢小蠹由20世纪90年代的7.9%,迅速增长到目前的57.3%。[结论]在云南,经过20年种群演替,之前云南切梢小蠹一支独大危害松林的局面,已转变为云南切梢小蠹和横坑切梢小蠹角力共同危害松林,预示当地松林尤其是云南松林正处于亚健康或不健康的状况,结果为云南省切梢小蠹的监测和防控提供了新的科学数据支持。 相似文献
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【目的】明确聚集信息素对横坑切梢小蠹诱捕量与不同危害程度的云南松林有虫梢率之间的关系,为横坑切梢小蠹种群监测与防治提供技术支持。【方法】采用随机抽样法,调查云南省祥云县普淜镇和下庄镇2个样地云南松林内切梢小蠹的危害情况,并在由梢部危害转至干部危害期利用聚集信息素诱捕横坑切梢小蠹成虫,分析横坑切梢小蠹在梢转干时期的种群变化规律及有虫梢率与诱捕量之间的关系。【结果】普淜和下庄2个样地横坑切梢小蠹和云南切梢小蠹是优势种。普淜样地中横坑切梢小蠹占49. 75%,雌雄比为1. 06∶1;云南切梢小蠹占50. 25%,雌雄比为1. 32∶1。下庄样地中横坑切梢小蠹占54%,雌雄比为1. 45∶1;云南切梢小蠹占46%,雌雄比为1. 88∶1。2样地中横坑切梢小蠹蛀梢期树冠有虫梢率从上到下依次降低,普淜样地有虫梢率约为下庄样地的10倍。2样地横坑切梢小蠹的诱捕量在整个梢转干期呈现相同的规律,成虫扬飞均始于11月中旬,终见于翌年5月下旬,扬飞高峰期是3月初至4月下旬。诱捕器中天敌种群数量与横坑切梢小蠹数量有明显的跟随现象。诱捕器中横坑切梢小蠹雌雄性比在1∶1. 09～1. 71之间,雄性个体数量明显多于雌性。横坑切梢小蠹林间有虫梢率(y)与诱捕量(x)之间呈线性正相关,其中在高虫口密度普淜样地拟合函数关系式为y=0. 002 4x+0. 060 1(R^2=0. 67),低虫口密度下庄样地拟合函数关系式为y=0. 003 2x-0. 004 3(R^2=0. 71)。【结论】了解高、低虫口密度下横坑切梢小蠹在云南松树冠中的分布规律,利用聚集信息素诱捕可作为监测横坑切梢小蠹种群变化的有效方法,且诱捕量与林间有虫梢率呈线性正相关,诱捕量可反应横坑切梢小蠹在蛀梢期的有虫梢率。 相似文献
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1997～1999年，在不同试验点的云南松蠹害林分中设置饵木堆、整株饵木和活立木引诱松小蠹试验。研究结果表明，几种方法对松小蠹均有一定的引诱效果。设置的衰弱木饵木堆诱虫效果明显高于健康木饵木堆；在饵木堆上加置MBXS，（-）APX或（-）APX+YS复合剂，诱虫量比不加置这些聚集信息化合物的饵木堆增加4倍以上。试验所用窗式诱捕器以寄主天然化学气味物质为诱饵，对转干期成虫具有较高而稳定的诱捕量，且设置检查方便、价格低廉，适用于梢转干期林间松小蠹诱捕和种群动态监测；活立木上加置（-）APX+YS复合剂，对各时期松小蠹成虫均有一定引诱作用，可用于梢部小蠹种群动态监测。 相似文献
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云南松饵木、活立木林间引诱松小蠹的试验 总被引：5，自引：1，他引：4
1997－1999年，在不同试验点的云南松蠹害林分中设置饵木堆、整株饵木和活立木引诱松下蠹试验。研究结果表明，几种方法对松小蠹均有一定的引诱效果。设置的衰弱木饵木堆诱虫效果明显高于健康木饵木堆；在饵木堆上加置MBXS，（－）APX或（－）APX＋YS复合剂，诱虫量不加置这些聚集信息化合物的饵木堆增中4倍以上。试验所用窗式诱捕器以寄主天然化学气味物质为诱饵，对转干期成虫具有较高而稳定的诱捕量，且设置检查方便、价格低廉，适用于梢转干期林间松下蠹诱捕和种群动态监测；活立木上加置（－）APX＋YS复合剂，对各时期松小蠹成虫均有一定引诱作用，可用于梢部小蠹种群动态监测。 相似文献
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试验表明,聚集信息素诱捕器是一种先进的诱杀松纵坑切稍小蠹与无公害监测的测报防治工具,松纵坑切稍小蠹危害轻度以下松林内诱捕量大,在虫情监测、测报防治方面发挥着重要作用。 相似文献
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以云南省曲靖市沾益、陆良县遭受纵坑切梢小蠹危害的云南松林为样区,应用NOAA/AVHRR、LandsatTM、CBERS-1 CCD和EOS/MODIS 4种卫星遥感数据,对其受纵坑切梢小蠹的重度危害区和健康林分进行了光谱信息的分析。据此,初步提出了两种监测模型,差变率(DR)模型和灾害指数(DI)模型,可用于区分典型的云南松健康林分和遭受纵坑切梢小蠹重度危害的林分。表明若DR值较大,云南松林的健康状况较好;反之DI值越大,林分受到纵坑切梢小蠹危害的程度越重。 相似文献
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松小蠹综合控制技术研究 总被引：4，自引：6，他引：4
为达到持续控制纵坑切梢小蠹(简称松小蠹)危害的目的，进行了松小蠹与云南松林分之间的关系、抚育间伐控制蠹害效果、蠹害木清理技术、聚集信息化合物引诱剂筛选及林问引诱技术、生物防治、化学防治等系列松小蠹综合控制技术研究。通过研究，初步探明了云南松林分与松小蠹危害之间的关系及受害林分内害虫的演变情况；证实了松小蠹生活史中姐妹代的存在，摸清了姐妹代各虫态出现的时期、种群数量，为松小蠹的防治提供了科学依据；筛选出4种效果较好的引诱剂配方及两种可供推广的诱捕器，研究了引诱剂林间引诱、测报方法及应用粉拟青霉菌杀虫剂防治扬飞期成虫技术，提出了一套完整的松小蠹综合控制措施。 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