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小蠹虫是世界性大害虫，特别是对松树危害极大，猖獗时常可造成林木成片枯死，其生活隐蔽，繁殖迅速，在造成林木枯萎前不易被人们发现。但衰弱森及某些种类的性外激素对其有很强的吸引力，诱集效果显著，可作为重要的监测手段。该虫主要发生在立地条件差，林地卫生条件不好或由其它种种上原因导致树森生长衰弱的林分。因此，其预防措施主要是选用良种壮苗，进行了适树营造混交林；加强监测，及时消灭虫源基地。其防治策略及研究发展 相似文献
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在老秃顶子国家级自然保护区共采到小蠹虫29种,隶属4亚科15属,其中红松根小蠹Hy-lastes plumbeusBlandford、东北四眼小蠹Polygraphus sachalinensisEggers、中穴星坑小蠹Pityo-genes chalcographasLinnaeus、落叶松八齿小蠹IpssubelongatusMotschuleky、六齿小蠹I.acuminatusGyllenhal等为优势种,主要危害衰弱木、濒死木、枯萎木及风倒雪压木等,少数种类如纵坑切梢小蠹Tomicus piniperda Linnaeus、黄须球小蠹Sphaerotrypes coimbatorensisStebblng等危害健康树木。不同海拔高度及不同类型的林分中,小蠹虫的种类存在明显差异。及时清除、集中处理风倒木是控制虫源,减轻危害的重要措施。 相似文献
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秦岭华山松小蠹生态位研究 总被引：31，自引：8，他引：23
通过对秦岭林区海拔１６００～２２００ｍ的中山地带华山松小蠹虫种类和生态位的研究,结果表明：在秦岭林区入侵危害寄主华山松的小蠹虫有１９种,其中能构成竞争和共存的小蠹虫主要有１１种。虽然,这１１种小蠹虫具有各自不同的生态位宽度,且存在不同程度的生态位重叠,但各小蠹虫可依据其对寄主树木营养和空间需求的不同、种群密度的相互制约,以及入侵寄主树木时序的差异达到竞争的平衡和共存。秦岭华山松小蠹生态系统的建立,首先是由华山松大小蠹入侵健康华山松,并通过携带蓝变真菌入侵寄主树木,迅速克服寄主树木抗性系统,使寄主树木树势衰弱;其次松六齿小蠹、暗额星坑小蠹和松十二齿小蠹,作为秦岭华山松的主要次期性小蠹,迅速入侵衰弱的寄主华山松;最后其它次期性小蠹虫入侵寄主树木,利用寄主华山松剩余营养和空间。从而实现秦岭华山松立木小蠹生态系统的动态稳定。 相似文献
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To preserve biodiversity in managed forest landscapes dead and living trees are retained at final cuttings. In the present study we evaluated the effect of these practices for saproxylic (wood-dependent) beetles inhabiting dead aspen trees (Populus tremulae). For saproxylic beetles, tree retention at final cuttings can be expected to be especially valuable for species adapted to sun-exposed dead wood, a substrate that only rarely occurs in well managed forest stands. Therefore, the current evaluation was conducted as a comparison of species richness, species density (number of species per sample), assemblage composition and occurrence of individual species between clear-cuts, where aspen trees were retained, and closed forest stands with aspen trees. The study was conducted in central Sweden and the beetles were sampled by sieving of bark from CWD (coarse woody debris) of aspen. There was no significant difference in rarefied species richness between forest and clear-cut sites. Species composition differed significantly between the two stand types. Generalized linear mixed-effects models predicted the species density to be 34% lower in CWD objects in forest sites than on clear-cuts. This pattern could partly be explained by differences in CWD diameter, decay class and bark types between the two stand types (clear-cut/forest). Stand type was a significant predictor of occurrence in individual CWD objects for 30% of analysed individual beetle species. For all species except one, the variable stand type predicted higher occurrence on clear-cuts than in forest stands. To conclude, our results demonstrate that retention of aspen on clear-cuts contributes to population recruitment of a different assemblage of species than CWD within stands. 相似文献
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我国天牛虫灾的成因、现状与对策 总被引：7，自引：0，他引：7
天牛是我国危害最严重的林木害虫.虫灾的成因涉及天牛习性、环境条件和防治技术3个方面.目前的防治措施有一定的局限,对危害部位高和大面积防治还缺乏简便实用的措施.天牛研究方面有待解决的问题主要有:(1)混交林在天牛治理中的地位与控灾机制;(2)人工林经营模式;(3)天牛成虫的化学生态学;(4)林木对天牛的抗性机制.天牛虫灾的治理应坚持预防为主的方针,通过人工林栽培制度和经营模式变革,合理利用林木抗虫性,营造生态防虫林.进而研究出配套的虫害管理模式和林分经营模式,实现天牛虫灾可持续治理目标. 相似文献
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林木培育目标应根据林分立地条件类型、林分生长类型等级、森林经营集约度和社会材种需求综合确定。通过林木定向培育提早主伐年龄以获得较高目的材种产量。对大径材培育主伐年龄应先与工艺成熟龄比较后确定。良种化林木培育是森林经营水平的重要标志，与Ⅰ类林分相比仍提早主伐年龄，增加材种产量１倍左右。应具体分析目前速生丰产林生长状况，林龄面积分布等，调整林木培育目标和主伐年龄，以保证森林资源的永续利用。 相似文献
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Timo Pukkala 《林业研究》2018,29(2):261-272
Forest management in several boreal countries is strongly focused on conifers because they are more productive,the technical quality of their stems is better,and their wood fibers are longer as compared to broadleaves.Favoring conifers in forest management leads to simple forest structures with low resilience and diversity.Such forests are risky in the face of climate change and fluctuating timber prices.Climate change increases the vitality of many forest pests and pathogens such as Heterobasidion spp.and Ips typographus L.which attack mainly spruce.Wind damages are also increasing because of a shorter period of frozen soil to provide a firm anchorage against storms.Wind-thrown trees serve as starting points for bark beetle outbreaks.Increasing the proportion of broadleaved species might alleviate some of these problems.This study predicts the long-term(150 years) consequences of current conifer-oriented forest management in two forest areas,and compared this management with silvicultural strategies that promote mixed forests and broadleaved species.The results show that,in the absence of damages,conifer-oriented forestry would lead to 5–10% higher timber yields and carbon sequestration.The somewhat lower carbon sequestration of broadleaved forests was counteracted by their higher albedo(reflectance).Mixed and broadleafforests were better providers of recreational amenities.Species diversity was much higher in mixed stand and broadleaf-oriented silviculture at stand and forest levels.The analysis indicates that conifer-oriented forest management produces rather small and uncertain economic benefits at a high cost in resilience and diversity. 相似文献
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Kihachiro Ohba 《Forest Ecology and Management》1983,6(3):245-262
Forestry practice differs from agricultural crops practice owing to the huge size of trees, their longevity and the variety of uncontrollable conditions under which they grow. Even with intensive forest management, the actual effects of investment of labour and materials in the forest seem to be fairly small because of the size of the forest and the long harvest rotation. Since we expect to produce both a higher quantity and a higher quality of timber with intensive forestry, it is very important to have adequate counter-measures to the fatal or destructive factors which affect forest establishment and growth. In Japan, in the field of forest tree breeding, we are making maps as information sources for decision making, in which iso-lines show the degrees of damage due to fatal factors such as pests and diseases. If there is more than one fatal factor overlapping in an area, it might be difficult to grow forests for commercial purposes. We have to decide how to use the forest land in these areas, or how to take counter-measures such as tending, chemical control, genetic improvement or even a change in the tree species. As forestry has a long harvest rotation, it is necessary to have ‘a quality control system’ in management, in which a follow-up assessment of planting materials, tending techniques in combination with site conditions, and fatal factors will be made. In this situation, forest tree improvement (breeding) seems to be of prime importance in intensive forest management in the future. 相似文献
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报道了松墨天牛成虫活动期间,在马尾松-栎类次生混交林、马尾松-湿地松人工林和黄山松天然林3种不同林分中,应用M99-1引诱剂诱捕钻蛀性松甲虫种类、主要钻蛀性松甲虫成虫种群数量及其比率和不同诱捕期松墨天牛雌成虫孕卵量及其比率的情况.研究结果显示,M99-1引诱剂诱获鞘翅目害虫达26种,其中钻蛀性松甲虫达14种,占诱获种类的53.8%.马尾松角胫象、松墨天牛种群数量比率最高,分别达57.3%～69.8%和27.2%～29.3%.3种不同松林林分中,短角幽天牛、褐幽天牛、薄翅锯天牛等其它主要钻蛀性害虫的数量比率也较高.不同诱捕期松墨天牛雌成虫平均孕卵量及其比率,以活动前期(6月下旬前)为最高,分别达16.9粒和41.9%.M99-1引诱剂诱捕是监测松林钻蛀性松甲虫种群动态和降低其虫口密度的重要方法. 相似文献
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报道了松墨天牛成虫活动期间 ,在马尾松 -栎类次生混交林、马尾松 -湿地松人工林和黄山松天然林 3种不同林分中 ,应用 M99-1引诱剂诱捕钻蛀性松甲虫种类、主要钻蛀性松甲虫成虫种群数量及其比率和不同诱捕期松墨天牛雌成虫孕卵量及其比率的情况。研究结果显示 ,M99-1引诱剂诱获鞘翅目害虫达 2 6种 ,其中钻蛀性松甲虫达 14种 ,占诱获种类的 5 3.8%。马尾松角胫象、松墨天牛种群数量比率最高 ,分别达 5 7.3%～ 69.8%和 2 7.2 %～ 2 9.3%。 3种不同松林林分中 ,短角幽天牛、褐幽天牛、薄翅锯天牛等其它主要钻蛀性害虫的数量比率也较高。不同诱捕期松墨天牛雌成虫平均孕卵量及其比率 ,以活动前期 (6月下旬前 )为最高 ,分别达 16.9粒和 4 1.9%。 M99-1引诱剂诱捕是监测松林钻蛀性松甲虫种群动态和降低其虫口密度的重要方法 相似文献