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陆河县林业有害生物发生防治现状与防控对策 总被引:2,自引:0,他引:2
文章针对目前陆河县林业有害生物发生危害的严峻形势与防控现状,指出林业有害生物防治与检疫工作中存在的主要问题,对林业有害生物防控对策进行探讨,并提出林业有害生物防控的建议。 相似文献
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指出了随着社会的发展与进步,林业有害生物防控问题越来越受到重视,林业有害生物防控措施在现实生活中具有重要的意义。探讨了关于林业有害生物防控问题并提出了防控措施。 相似文献
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指出了随着社会的发展与进步,林业有害生物防控问题越来越受到重视,林业有害生物防控措施在现实生活中具有重要的意义。探讨了关于林业有害生物防控问题并提出了防控措施。 相似文献
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新疆林业有害生物防控网络平台设计及实现 总被引:1,自引:0,他引:1
为加强新疆林业有害生物防控体系建设,及时掌握林业有害生物发生动态,分析判断其发展趋势,本系统采用浏览器、网络服务器、有害生物信息数据库、地理信息系统、移动网络技术,以及 HTTP、HTML、Java等技术,建立新疆林业有害生物防控网络平台。平台的核心功能模块包括:林业有害生物信息发布、林业有害生物检索,林业有害生物防控体系管理、林业有害生物监测信息采集系统、林业有害生物防治管理及决策。通过该平台实现了县、乡两级测报点的监测数据采集、传输、统计,信息处理分析、专家咨询、辅助决策等功能。 相似文献
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危险性、检疫性等的林业有害生物对上海市林业的发展有构成重大威胁的趋势。从上海林业有害生物防控工作面临的压力以及监测预警与应急防控体系建设现状出发,对迎世博上海市危险性林业有害生物预警与防控体系的构建,从项目建设的目标、预警防控流程技术路线、建设方案布局内容等方面进行探讨,以期为建立健全完善的上海市林业有害生物预警和防控体系提供有益的借鉴。 相似文献
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通过对青海三江源区林业有害生物发生现状的调查研究以及对治理存在的问题进行探讨分析,总结预测出林业有害生物发展趋势,并就当前林业有害生物发生状况提出防控建议,可有效地促进全省林业有害生物的防控工作,为林业生产提供技术支撑。 相似文献
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D. G. Hunt 《Wood Science and Technology》1989,23(4):323-333
Summary Non-linearity of softwood in axial mechano-sorptive creep during moisture cycling can be characterised as departure from linear behaviour. Linear behaviour is shown by experimental measurement to be a gradual approach to a creep limit with exponentially decreasing increments of compliance, Ji, per moisture cycle, when tested under a constant stress. On the other hand, when the stress is progressively increased by a small increment after each moisture cycle, the compliance increments will progressively increase, having a value of
, where n is the cycle number. By subtracting one compliance increment from the succeeding one, the value of Ji can be obtained. Analysis of experimental results in bending tension and compression showed that the compression test pieces departed from linearity at total strains around 0.14% to 0.15%, the bending test pieces showed slight evidence of non-linearity at about the same strain, whilst the tensile pieces were approximately linear up to 0.18% strain.This project was supported by the U.K. Science and Engineering Research Council and by the European Commission 相似文献
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文章简要地分析了围垦湖沼、上游截流、过度利用及工艺技术落后等人为因素对湿地资源的破坏情况与负面影响,给人们赖以生存的湿地生态环境带来严重的不可逆转的后果,并有针对性地提出了几点建议。 相似文献
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森林病虫害防治是国家减灾工程的重要组成部分,对保护森林资源,改善生态环境,促进国民经济和社会可持续发展具有十分重要的意义。 相似文献
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我国桉树木材性质及其变异规律研究进展 总被引:1,自引:0,他引:1
概述了国内桉树木材解剖性质、物理力学性质、化学性质及其变异规律的研究现状,对桉树木材性质变异的影响因子及其材性遗传相关性研究进行了总结,最后分析其存在的问题,并展望了桉树材性遗传改良的研究前景。 相似文献
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以德国南部小城镇加米施-帕滕基兴(Garmisch-Partenkirchen)市为例,在介绍该市园林绿化概况的基础上,重点介绍其民居庭院绿化与阳台绿化的特色;并对如何更好地发展中国小城镇绿化进行了探讨。
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The composition of the endophytic fungal assemblages in Quercus cerris, Q. pubescens and Q. robur, three oak species most susceptible to decline, was investigated in Fagarè (Padova), Ulignano (Pisa), and Radda in Chianti (Firenze). The endophytic assemblages were studied as a function of health status of the whole tree and of twigs and leaves. The effect of station altitude was tested on Q. cerris. Samples were gathered from healthy and declining trees. In April (bud opening time) 20 twigs and 10 leaves were collected from each tree. Fungi were isolated from twig segments and leaf portions. A total of 23 fungal genera with 27 different species were isolated, in addition to a few sterile mycelia. Eleven species were found to be common to all three oak species, while other species were found only on one oak species, suggesting host specificity. Among the fungal species isolated, some were known to be pathogenic (Apiognomonia quercina, Colpoma quercinum, Diplodia mutila, Phomopsis quercina). The colonization frequency (CF) of pathogenic species varied between 0.9% for A. quercina in Q. cerris and 60.2% for P. quercina in Q. robur. Analysis of variance showed a statistically significant difference among the oak species tested. The CF was higher in declining trees in comparison with healthy trees, and also in twigs vs. leaves. The CF was found to be higher for Q. cerris trees growing at sea level as compared with those situated at an elevation of 350–400 m. In stands where, on account of particular ecological conditions, pathogenic behaviour is displayed simultaneously by more than one endophytic fungal species, trees accentuate their decline. 相似文献
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我国山苍子开发利用的现状与发展对策 总被引:3,自引:0,他引:3
为给我国山苍子产业的发展提供决策依据,详细介绍了山苍子的习性、栽培现状、主要用途,就我国山苍子开发利用中存在的一些问题进行分析,并从加强品种选优、开展集约化经营技术研究、加强山苍子资源的统一管理和利用等方面提出了发展对策。 相似文献
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森林分类区划是为了解决天然林的修养生息和恢复发展而提出的,但禁伐区、限伐区、商品林经营区划分在实施过程中存在一些问题。文章主要针对其存在的问题,提出一些可行性的建议和对策。 相似文献
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