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1.
前不久,重庆市政府召开了全市林业有害生物防治工作会议,下发了《重庆市人民政府关于进一步加强林业有害生物防治工作的意见》,正式吹响了重庆“十一五”林业有害生物防治工作的号角,揭开了重庆市林业有害生物防治工作崭新的一页。如何搞好重庆林业有害生物防治工作?采用哪些办法和措施使重庆林业有害生物防治工作落到实处?今后林业有害生物防治工作有何打算?带着诸多疑问,记者采访了重庆市林业局局长周克勤。记者:重庆市林业有害生物防治工作取得的成绩有目共睹,其主要经验有哪些?周克勤:近年来,重庆市全面完成了国家林业局下达的“四率”… 相似文献
2.
森林资源是自然资源的重要组成部分,林业有害生物是威胁我国森林健康的主要因素之一.因此,做好林业有害生物防治工作至关重要.笔者分析了同朔地区林业有害生物防治工作的现状,针对其中存在的问题,提出了加强有害生物监测预警工作、提高林业有害生物防治技术、强化林木检疫工作等解决对策,旨在为今后开展林业有害生物防治工作提供参考. 相似文献
3.
4.
广东林业有害生物防控现状及对策的思考 总被引:1,自引:0,他引:1
文章回顾了广东省林业有害生物防治工作近30年的历程,总结了防治工作经验,分析了当前林业有害生物防治工作现状和问题,思考了当前和今后一个时期林业有害生物防治工作的策略和措施。 相似文献
5.
3月22日,全区林业有害生物防治工作会议在南宁召开。会议的主要内容是:贯彻落实全国林业有害生物防治工作会议和全区林业局长会议精神,总结近年来全区林业有害生物防治工作,表彰先进,分析全区林业有害生物防治工作形势,统一认识,明确工作思路,研究部署当前和今后一个时期林业有害生物防治工作。 相似文献
6.
林业有害生物防治形势与发生原因及对策 总被引:3,自引:0,他引:3
分析了当前林业有害生物发生与防治形势及原因,并从提高林业有害生物防治意识;加强林业有害生物预测预报工作;加大森防科技含量,改进防治手段;加强林业有害生物检疫,严防危险性有害生物侵入;精心组织,开展林业疫情普查;加大资金投入,保证防治需要等六个方面提出了林业有害生物防治应对措施。 相似文献
7.
林业有害生物防治工作是林业建设的重要组成部分,承担着保护森林资源、维护生态安全、推进生态建设、促进生态文明的重任,是林业发展的重要保障.本文分析了当前林业有害生物防治工作中存在的主要问题和制约林业有害生物防治的因素,并提出了林业有害生物防治对策. 相似文献
8.
立足于雅安市雨城区林业有害生物防治工作现状,文章分析了当前该区重大林业有害生物防治工作存在的主要问题,提出了进一步搞好雨城区重大林业有害生物防治工作的对策与建议。 相似文献
9.
介绍了新疆阿尔泰山福海分局林业有害生物测报点近几年采取的主要林业有害生物无公害防治措施,分析了当前开展林业有害生物防治工作的重要性以及主要制约因素,结合多年林业有害生物防控工作经验,提出了有效的对策。 相似文献
10.
介绍了永州市林业有害生物发生危害情况及防治工作开展现状,分析了该市林业有害生物防治工作面临的形势及存在的问题,就如何应对该市当前严竣的林业有害生物防治形势提出了相应对策。 相似文献
11.
This study investigated the dynamic modulus of elasticity (DMOE) of wood panels of Fraxinus mandshurica, Pinus koraiensis, and Juglans mandshurica using the natural frequency measurement system of fast Fourier transform (FFT). The results were compared with the static
modulus of elasticity (E
S) tested by a mechanical test machine. The results show a significant correlation between E
S, transverse vibration DMOE (E
F), and longitudinal vibration DMOE (E
L). For all of these species, the correlation between E
S, E
F and E
L is more significant than the individual species, which indicated that the FFT method is universal. The correlations between
E
S and sample’s density (ρ) are significant, but the correlation coefficient of E
S and ρ is lower than those between E
F, E
L and E
S. The E
S of wood is more accurately tested by the analysis based on FFT measurement than by the estimation based on density.
__________
Translated from Scientia Silvae Sinicae, 2005, 41(6): 126–131 [译自: 林业科学, 2005, 41(6): 126–131] 相似文献
12.
Bacterial blight is considered one of the most serious diseases affecting the genus Juglans. Artificial inoculations with Xanthomonas campestris pv. Juglandis were performed in the field by spraying seedlings of Juglans cinerea, Juglans hindsii, Juglans mandshurica, Juglans nigra, Juglans regia and Juglans sieboldiana. Juglans nigra, J. cinerea ana J. sieboldiana proved to be the most resistant. The multiplication ability of Xanthomonas campestris pv. corylina, X. c. pv. juglandis, and X. c. pv. campestris was evaluated by injecting 2-year-old seedling leaves of J. mandshurica, J. nigra and J. regia. The bacterial growth was monitored in the infected tissue over 12 days. Xanthomonas c. pv. juglandis exhibited a high growth rate and induced black greasy spots in J. mandshurica and J. regia; X. c. pv. campestris grew in leaf tissues without inducing symptoms, X. c. pv. corylina showed a very low growth rate. None of the tested bacterial strains multiplied in the leaves of J. nigra. This confirms the results obtained in the field tests. Juglans regia was the most susceptible among the walnut species tested. 相似文献
13.
Hitoshi Sakio 《Journal of Forest Research》2005,10(4):341-346
The effects of flooding on growth of seedlings were compared over a 7-month period (April–November) among six different woody species: Aesculus turbinata, Cercidiphyllum japonicum, Fraxinus platypoda, Pterocarya rhoifolia, Pterostyrax hispida, and Quercus mongolica var. grosseserrata. Flooding reduced the shoot length of F. platypoda, P. rhoifolia, C. japonicum, P. hispida, and Q. mongolica var. grosseserrata seedlings but did not affect that of A. turbinata seedlings. Among control seedlings, shoot elongation occurred once in A. turbinata and twice in F. platypoda and Q. mongolica var. grosseserrata; the other species continued to grow from April to August. Among the flooded plants of all species, shoot elongation occurred only once at the beginning of the growing season. On August 25, flooding significantly reduced the number of developed leaves as compared with control plants except for A. turbinata. In the flooded plants except for F. platypoda, leaf fall began on June 30; in controls, by contrast, the number of developed leaves increased until August 25. Flooding reduced the total dry weight increment in all species. The survival ratio of flooded plants after the experiment differed with species. All of the F. platypoda and A. turbinata seedlings survived the flooding treatment, while only 20% of P. hispida and 30% of Q. mongolica var. grosseserrata survived. Flooding seriously affected the growth of riparian pioneer species including P. rhoifolia, C. japonicum, P. hispida, and Q. mongolica var. grosseserrata. The effects of flooding on growth of the seedlings differed with the tree species because of differences in leaf-emergence pattern and physiological flood tolerance. The responses of tree seedlings to flooding reflected species habitats and growth patterns. 相似文献
14.
[目的]分离并量化土壤自养呼吸和异养呼吸,探讨各自贡献率及其随季节变化的动态特征。[方法]采用壕沟法和气体红外分析法,研究黄河小浪底库区山地栓皮栎人工林土壤总呼吸、自养呼吸和异养呼吸速率的季节动态变化、贡献率和环境影响因子。[结果]表明:栓皮栎人工林总土壤呼吸、自养呼吸和异养呼吸均呈夏季速率高、冬季速率低。栓皮栎土壤总呼吸、自养呼吸及异养呼吸速率与5 cm土壤温度均呈极显著指数相关,温度敏感性系数Q_(10)值大小为自养呼吸(3.40)异养呼吸(2.90)土壤总呼吸(2.45);栓皮栎土壤总呼吸、自养呼吸、异养呼吸速率与0 10 cm土壤体积含水量均显著线性相关;土壤总呼吸、自养呼吸速率与0 10 cm土壤电导率显著相关。土壤总呼吸和异养呼吸的温度敏感系数Q_(10)值均在冬季最大,夏秋季最小;而自养呼吸的Q_(10)值则呈相反的变化趋势。栓皮栎人工林自养呼吸和异养呼吸对土壤总呼吸的月贡献率为13.23%37.33%和62.67%86.76%,且自养呼吸的贡献率与土壤温度的季节变化规律相似。土壤总呼吸、异养呼吸与自养呼吸的CO2年通量分别为1 616.41、1 199.39、417.02 g·m~(-2)·a~(-1)。[结论]经过区分与定量化土壤总呼吸及其组分,确定异养呼吸为本研究区栓皮栎人工林土壤总呼吸的主要组分,作用于异养呼吸的生物与非生物因子均能显著影响整个森林生态系统表层CO_2总排放通量的大小,进一步为该研究区森林生态系统碳循环与能量流动的进一步量化研究提供参考。 相似文献
15.
Wu Xingyin Zhang JinghuaForest Pest Control Quarantine Station of Archeng City of Heilongjiang ProvinceXiang Cunti Li Guisheng '''' Shao Zhongwen Liu Xiaoguang Ma LiyaNortheast Forestry UniversityZhang Xianwen Li Zhuo Xie Guicai Dang WenqiangArcheng Forestry Bureau of Heilongjiang Province 《林业研究》1991,2(2):7-16
The poplar bacterial canker caused by Erwinia sp is a serious disease spreading inmost parts of Northeast China,where poplars are cultivalted.The disease seriously infects thosepoplars belonging to section Aigeiros or the intersection hybrids of section Tacamahaca and section Aigeiros and their clones.Five fine poplar cultivars resistant to the bacterial canker have been ob-tained by screening tests.They are Lz_2(Populus simonii×nigra var.italica),A_(15)(P.×sp.)613(P.×sp.),A_(102)and A_(98)(P.simonii×sp.)T following chemicals are obviously effective,such as:50%DT germicide ,40% XF-136 and 10% C.C.M.A.or 12.5% ramphencol and 50,000 ppm/mlvalidamycin,with which the stems or roots can be watered. 相似文献
16.
The technology of liquefying processed-waste bamboo with phenol is investigated by single factor trials and an orthogonal
design. We studied the preparation technology and properties of adhesives from this phenol-liquefied bamboo with formaldehyde
(BPF). The results show that temperature has a significant effect on liquefaction. The effect of the mass ratio of phenol
to bamboo comes second and the catalyst dosage within the range of 2%–4% is the least effective. The optimum conditions of
liquefaction are as follows: a mass ratio of phenol to bamboo 3.5, a catalyst dosage of 4%, liquefying temperature 145°C and
liquefying time 60 min. The liquefaction rate of bamboo reached 99.1%. For the preparation of the adhesive, a mass ratio of
liquefied bamboo products to formaldehyde (37%) is 100 to 164.8–199.5, while the ratio 100 to 108.2 is the best. This adhesive
has a lower curing temperature than that of normal PF resin. At a hot-press temperature of 130 or 140°C, this new adhesive
provides excellent bonding strength of plywood. The most favorable temperature for hot-pressing is 140°C.
__________
Translated from Chemistry and Industry of Forest Products, 2007, 27(6): 65–70 [译自: 林产化学与工业] 相似文献
17.
Yingcheng Hu Fenghu Wang Jiyou Gu Yixing Liu Tetsuya Nakao 《Wood Science and Technology》2005,39(6):439-447
The effects of grain angle, thickness of face veneer, and shelling ratio on dynamic modulus of elasticity (E) of veneer-overlaid particleboard composite (VOP) were examined by using nondestructive test. In this study, the possibility
that E of VOP can be predicted by means of some empirical formula was also discussed. This study has shown that grain angle, thickness
of face veneer, and shelling ratio have substantial effects on E of VOP. The E at 0° of grain angle of face veneer was the largest, decreasing rapidly with increase in the grain angle. The lowest value
of E occurred at 90° of grain angle of face veneer. The relationship between grain angle of face veneer and E of VOP can be expressed in the form of Jenkin’s and Hankinson’s equations. The orthotropic properties of wood and VOP defined
as the ratio E
0/ E
90 were 25.7 for wood and 4.7 for VOP. When the grain direction of face veneer was parallel to the length of the specimens,
the E of VOP increased with increasing shelling ratio. VOP increased E from 125 to 179% over that of the particleboard and veneer thickness from 2.1 upto 3.6 mm. However, when the grain direction
of face veneer was perpendicular to the length of the specimens, the E of VOP decreased with increasing shelling ratio. VOP decreased E from 23 to 41% over that of the particleboard and veneer thickness from 2.1 upto 3.6 mm. The relationship between E of VOP and face veneer thickness can be expressed in the form of a second-order parabolic equation. Rule of Mixture (ROM)
can be used to predict E of VOP from the E of wood element and particleboard element. 相似文献
18.
Summary The wood, composed of alternate earlywood and latewood lamellae, forms a statically indeterminate system with two redundants. The redundant forces are the shearing forces arising at the edge of the boundary between earlywood and latewood in the longitudinal and in the tangential directions of wood. By determining the redundant forces according to the theory of statically indeterminate systems, we know the state of stress and the state of detormation of the wood element and thus can determine its shrinkage and stresses in the longitudinal, tangential and radial directions.
Zusammenfassung Holz ist aus Früh-und Spätholzlamellen aufgebaut und bildet damit ein statisch unbestimmtes System mit zwei statisch unbestimmten Größen. Diese statisch unbestimmten Größen sind die Scherkräfte, die in longitudinaler und tangentialer Richtung an den Kanten der Grenzschicht zwischen Früh-und Spätholz entstehen. Bestimmt man die statisch unbestimmten größen nach der Theorie der statisch unbestimmten Systeme, so kennt man den Spannungs-und Verformungszustand der Gefügeteile des Holzes und ist damit in der Lage, scine Schwindung und Schwindspannungen in longitudinaler, tangentialer und radialer Richtung zu berechnen.相似文献
19.
大花葵花色苷抑菌功能研究 总被引:6,自引:0,他引:6
本项研究通过采用固体培养和液体培养的试验方法,进行大花葵花(Malvasylvestris)色苷对金黄色葡萄球菌、大肠杆菌和黑曲霉的抑菌试验。结果表明:大花葵花色苷对金黄色葡萄球菌有很强的抑制作用,而对大肠杆菌和黑曲霉没有抑制现象发生。在固体培养试验中大花葵花色苷随着浓度的增加,对金黄色葡萄球菌的抑制程度越大,当大花葵花色苷浓度为10g/L时抑菌圈平均直径为6mm,当浓度增加至30g/L时,抑菌圈平均直径为16mm。而且,高浓度的大花葵花色苷溶液对金黄色葡萄球菌有长时间的抑制作用。 相似文献
20.
M. T. Dumas 《Forest Pathology》1992,22(1):11-18
Pseudomonas fluorescens, Pseudomonas spp., Bacillus spp., Enterobacter spp., Serratia spp. and Agrobacterium radiobacter were isolated from root-free soils of the Boreal Mixedwood Forest of Ontario a, nd found to be capable of inhibiting the linear growth of Armillaria ostoyae in vitro. Isolates of P. fluorescens, Bacillus spp. and A. radiobacter were the most effective inhibitors of mycelial growth. To test the ability of the bacteria to suppress rhizomorph formation, A. gallica, which produces rhizomorphs in culture more consistently than does A. ostoyae, was used; only a small fraction of P. fluorescens and Bacillus spp. isolates were capable of preventing in vitro rhizomorph formation by A. gallica. 相似文献