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对元谋干热河谷引种的8种外来树种进行了抗旱性分析，发现水分利用效率从高到低的顺序依次是：窿缘桉、赤桉、柠檬桉、绢毛相思、肯氏相思、厚荚相思、大叶相思、马占相思。水分利用效率越高，对干热环境的适应性越强。8种外来树种适应干热河谷生境的旱性结构的特点是主根深、侧根多、栅栏组织和贮水组织发达、构成等面叶或近等面叶。桉树类树种的蒸腾速率较高，但能生存的主要机理根系分布深，主动供水能力强，补充了地上部分的水分消耗；而相思类则以发达的根系和较高的叶片保水能力来适应干热环境。 相似文献
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林武星 《中南林业科技大学学报(自然科学版)》2005,25(1):42-45
对闽南沿海沙地10种引种造林树种的速生性、丰产性和适应性进行了调查,并采用多目标决策方法进行了闽南沿海沙地引种树种评价研究.结果表明:在10种引种树种中,厚荚相思速生丰产性和适应性得分最高,综合评价值最大,纹荚相思综合评价值居第2,柠檬桉综合得分值最低;厚荚相思、纹荚相思和巨尾桉为闽南沿海沙地1级最适宜造林树种,刚果12号桉、大叶相思和马占相思为2级次适宜造林树种,毛娟相思、肯氏相思、卵果松和柠檬桉为第3级造林树种. 相似文献
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金沙江干热河谷地区的主要造林树种中,以马占相思、山毛豆、真珠相思、大叶相思、台湾相思、绢毛相思、坡柳在旱季游离脯氨酸累积较多;赤桉、泰国赤桉、柠檬桉、尾叶桉、大叶桉、新银合欢、苏门答腊金合欢、滇刺枣无明显差异。无论从种属间或种源地,还是不同生态类型,都看不出游离脯氨酸的累积与抗旱性之间有明显的相关关系。作者认为,用游离脯氨酸作为植物抗旱性指标有一定局部性,但用它作为某些树种在干旱胁迫时植物体发生变化的一个比较敏感的参数或指标则比较适合 相似文献
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对厚荚相思(Acacia crassicarpa)、马占相思(A.mangium)、肯氏相思(A.cuninghamia)进行引种造林试验.结果表明,在粤西造林后1~4 a,厚荚相思树高生长最快,肯氏相思次之,马占相思最慢,分别为5.57、4.92、4.08 m;但马占相思造林后第4年至第5年生长明显加快,造林后5 a,马占相思树高、胸径生长最快、生物量最大,分别为7.01 m、7.69 cm、32.1 kg,厚荚相思次之,分别为6.80 m、5.77 cm、16.72 kg,肯氏相思最差,分别为5.32 m、4.21 cm、13.48 kg.马占相思和厚荚相思适宜在肇庆市及粤西南地区推广. 相似文献
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闽南山地引种三种相思树生长效果及适应性评价 总被引：2，自引：0，他引：2
对闽南山地引种的 3种热带相思树的生长效果及适应性分析结果表明 :马占相思生长迅速 ,干形通直 ,9 5年生平均树高、胸径、单株材积及地上部单株生物量分别达 13 7m、19 7cm、0 2 0 6m3 和 10 7 6 0kg ,但其耐干瘠能力稍差且抗寒、抗风能力弱 ;厚荚相思生长也较为迅速且耐瘠簿、耐寒 ,但抗风能力差 ;肯氏相思生长状况远不如马占相思和厚荚相思好 ,但其耐寒且抗风能力较强。马占相思和厚荚相思可做为闽南丘陵山地短周期工业原料林树种 ,肯氏相思宜作为薪炭林和水土保持林树种。 相似文献
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沿海沙地木麻黄更新迹地6种相思树的水源涵养功能比较 总被引：1，自引：0，他引：1
对木麻黄更新迹地上引种的8年生6种相思树种林分涵养水源能力进行了比较,并以平潭2号木麻黄为对照,结果表明:与木麻黄相比,肯氏相思、厚荚相思和纹荚相思有更强的水源涵养能力,在6种相思中,地上部分持水量以厚荚相思为最高,达42.88 t.hm-2,大小排序为厚荚相思>肯氏相思>纹荚相思>卷荚相思>大叶直干相思>马占相思;根系土壤层的持水能力以肯氏相思的土壤蓄水量最大,达1 795.02 t.hm-2;林分总持水量以肯氏相思最高,达1 824.04 t.hm-2,其次为厚荚相思和纹荚相思,分别达1 770.75 t.hm-2和1 759.60 t.hm-2。从涵养水源的能力角度来评判,肯氏相思、厚荚相思和纹荚相思作为沿海木麻黄防护林更新树种,有一定前景。 相似文献
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对福建省长乐市大鹤国有林场的4年生大叶相思、肯氏相思、纹荚相思、厚荚相思、卷荚相思的各构件生物量分配率进行研究,结果表明:厚荚相思的总生物量最大,而卷荚相思的总生物量低于其他相思树种。5个相思树种各构件生物量分配率:肯氏相思、纹荚相思和卷荚相思的根部分配率较高,其中纹荚相思的根系生物量分配率最高,达46.69%,其次为肯氏相思,达44.59%;而大叶相思和厚荚相思的枝叶鲜重和生物量分配率较高,其中厚荚相思枝叶生物量最高,达76.71%,大叶相思达75.05%。从构件生物量的角度来看,肯氏相思和纹荚相思更适宜作为滨海沙地造林树种。 相似文献
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Thermogravimetric and differential thermal analyses techniques have been applied to investigate the thermal degradation characteristics
and chemical kinetics of Japanese cedar, cypress, fir, and spruce. The decomposition of the components could be modeled by
an Arrhenius kinetic expression. The kinetic parameters were extracted from the thermogravimetric data using least-squares
techniques. The heating rates used for the analyses were 10°, 5°, and 0.33°C/min; and the activation energy and reaction order
of the above woods were 7.54, 8.39, 2.87, and 7.88 kJ/mol and 0.71, 0.64, 0.44, and 0.63, respectively. Finally, carbonization
was done to produce charcoal from these woods under various operating conditions, and the charcoal was characterized in respect
to yield, heating value, electrical conductivity, and X-ray diffraction. The quality of the charcoal from fir was the best
among the four types of wood. The charcoal produced is inferior to binchotan (white charcoal) in respect to electrical conductivity
and crystalline structure.
Received: February 13, 2002 / Accepted: July 12, 2002
Acknowledgment The authors express their gratitude to Professor Yoshida of Applied Chemistry in Tokyo Metropolitan University for performing
the TG/DTA in his laboratory and for his valuable suggestions about the analyses. 相似文献
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Sasa Sofyan Munawar Kenji Umemura Fumio Tanaka Shuichi Kawai 《Journal of Wood Science》2008,54(1):28-35
This study focused on the effects of treatments of alkali, mild steam, and chitosan on the surface morphology, fiber texture,
and tensile properties of pineapple, ramie, and sansevieria fiber bundles. The fibers were treated with NaOH (2%), mild steam
(0.1 MPa), and chitosan solutions (4% and 8%). The properties of these treated fibers were characterized and compared with
the untreated fibers. Field emission scanning electron microscopy (FE-SEM) was used to observe the surface morphology of those
fibers. X-Ray diffraction (XRD) spectroscopy was used to observe the fiber textures. Tensile properties of the treated and
untreated fibers were also recorded. SEM micrographs showed that the surfaces of the NaOH-treated fibers were more damaged
than those of the steam-treated fibers. The 4% chitosan solution covered the fiber surface more uniformly than the 8% chitosan
solution. The steam-treated fibers had higher values of degree of crystallinity, crystallite orientation factor, and crystallite
size than the NaOHtreated fibers. Ramie fiber showed greater mechanical properties than the other fibers. The values of tensile
strength, Young’s modulus, and toughness of the steamtreated fibers, which were similar to those of the 4% chitosan-coated
fibers, were higher than those for the other treatments. 相似文献
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Behavioral responses,rate of mortality,and oviposition of western cherry fruit fly exposed to malathion,zeta-cypermethrin,and spinetoram 总被引：1，自引：1，他引：0
Western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), is a pest of sweet and tart cherry, Prunus avium L. (L.) and P. cerasus L., respectively, in western North America. This fly is commonly controlled with spinosad bait sprays. Spotted wing drosophila,
Drosophila suzukii Matsumura, is potentially a new pest of cherries in this region that could be a threat to orchards at the same time as R. indifferens. Drosophila suzukii apparently is not controlled using spinosad bait sprays, but may potentially be controlled using malathion, zeta-cypermethrin,
and spinetoram. However, how well these last three materials protect fruit against reproductively mature R. indifferens is not known. In laboratory observations, R. indifferens spent the least amount of time on cherries treated with zeta-cypermethrin, possibly because of its toxicity and irritant
effects. In laboratory experiments, zeta-cypermethrin killed flies more quickly than malathion and spinetoram, causing up
to 100% mortality 2 h after exposure. Zeta-cypermethrin prevented all oviposition when flies walked on dried residues for
20–25 min or were directly sprayed, and then exposed to cherries with dried residues, simulating exposure of mature female
flies in a treated orchard. Malathion and spinetoram reduced oviposition compared with controls, but did not prevent it, when
flies contacted residues or were directly sprayed at a high volume. Results suggest zeta-cypermethrin is the most effective
of the three materials at protecting cherries against mature R. indifferens and could be used in an integrated control program for it and D. suzukii. 相似文献
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We address the question of how credible knowledge that will contribute to more effective forest policy and management can
be produced. We argue that some forest-related knowledge-producing practices of professional scientists and of local people
are similar, and given the differences in the knowledge they produce, we explore how they might be used productively together
to create better understandings of forests with resulting better forestry practice and policy. Using a case study of participatory
forest ecology research, we demonstrate that when professional (conventional) scientists do research in collaboration with
local experts (civil scientists), the resulting knowledge can be more accurate and more policy relevant than they could produce
doing research on their own or only with other conventional scientists. 相似文献
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本文就核桃采收时间、脱皮方法及坚果分级标准进行了初步研究总结,为实现核桃优果优价、提质增效提供了切实可行的理论依据。 相似文献
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Lewis Clifford E. Burton Glenn W. Monson Warren G. McCormick W. C. 《Agroforestry Systems》1983,1(4):277-297
Agroforestry Systems - Native forages of southern United States are frequently low in nutrients and poorly digestible, while improved pastures are the opposite. Since this area produces rapid... 相似文献
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Seedling emergence, growth, and allocation of Oriental bittersweet: effects of seed input, seed bank, and forest floor litter 总被引：3，自引：0，他引：3
Joshua W. Ellsworth Robin A. Harrington James H. Fownes 《Forest Ecology and Management》2004,190(2-3):255-264
The establishment of invasive plant populations is controlled by seed input, survival in the soil seed bank, and effects of soil surface disturbance on emergence, growth, and survival. We studied the invasive vine Celastrus orbiculatus Thunb. (Oriental bittersweet) to determine if seedlings in forest understory germinate from the seed bank or from seed rain. We also conducted a greenhouse experiment to investigate the role of leaf litter mass and physical texture on seedling survival, growth, and allocation. In the understory of an invaded mixed hardwood forest, we measured seed input, seedling emergence with seed rain, and seedling emergence without seed rain. Mean seed rain was 168 seeds m−2: mean seedling emergence was 107 m−2, and there was a strong correlation between seed rain and seedling emergence. The ratio of seedlings to seed input (0.61) was close to the seed viability (0.66) leaving very few seeds to enter the seed bank. Seed bank germination under field conditions was low (1 seedling m−2). Soil cores were incubated in a greenhouse to determine seed bank viability, and germination from these soil cores did not occur. To determine how litter affects seedling establishment and growth, we measured seedling emergence and biomass allocation in a greenhouse experiment. Seeds were placed below intact and fragmented deciduous leaf litter in amounts ranging from zero to the equivalent of 16 Mg ha−1. Seedling emergence was not affected by fragmented litter, but decreased to <20% as intact litter increased to 16 Mg ha−1. Increasing litter resulted in greater allocation to hypocotyl and less to cotyledon and radicle, and this effect was greater in intact litter. C. orbiculatus seedlings achieve emergence through forest floor litter through plasticity in allocation to hypocotyl growth. The low survival of C. orbiculatus in the seed bank suggests that eradication of seedling advance regeneration and adult plants prior to seed rain may be an effective control strategy. However, the intact forest floor litter of an undisturbed forest will not prevent seedling establishment. 相似文献
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林地土壤pH值，磷，钾，有机质和水含量具有可变和可控性 总被引：1，自引：0，他引：1
对取自山西省北部不同地点、不同层次的土样的pH值、磷、钾、有机质、水含量的变化进行了研究。结果表明：林地土壤理化性质具有可变性的可控性。 相似文献