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61.
珍稀树种香果树的利用价值及实用繁殖技术   总被引:2,自引:0,他引:2  
香果树是我国特有单种属珍稀阔叶树种,属国家Ⅱ级重点保护野生植物,具有较高的推广价值。结合生产实践经验和目前有关科研进展,综合论述了香果树的开发利用价值以及关键培育技术,为开发利用香果树提供了科学理论基础。  相似文献   
62.
介绍了小叶榄仁的形态特征、生态学特性以及在汕头地区引种的生长表现。引种栽培结果表明:小叶榄仁生长和抗逆性表现良好,适合汕头等沿海地区作为庭园景观树种和行道树种,并总结了小叶榄仁的育苗及管理技术。  相似文献   
63.
文化设计理念在森林与湿地公园规划中的应用   总被引:6,自引:2,他引:6  
提出了文化设计的概念和理念体系,分别从文化的时空差异性、展示技术和表现形式上阐述文化设计的主要内容;提出主题、思想、美与爱以及与之相对应的形式上的真、认知上的善、感知上的美是文化设计的基本内容;并据此构建了文化设计的3个层面(主题、思想、美与爱)的设计符号体系;结合森林与湿地公园设计实践,分别从功利与审美相结合、爱与人文关怀、异质化与特化、符号化、大众潮流与时尚、亲和性与神圣化、共鸣与共震、个性化8个方面分析文化设计理念的应用与设计基本手法。  相似文献   
64.
黄檗药用林栽培技术研究   总被引:2,自引:0,他引:2  
黄檗是珍贵的材、药两用树种,由于不科学的开采和利用,资源受到严重破坏。本文针对黄檗的药用价值论述了药用林的栽培技术,并提出了保护和发展黄檗资源的建议。  相似文献   
65.
生物防火林带技术的科学基础和发展前景   总被引:4,自引:0,他引:4       下载免费PDF全文
生物防火林带技术是将特定常绿阔叶树种呈带状密植到易燃的植物群落中,用以预防和阻隔地表火及树冠火蔓延。研究表明,生物防火林带的防隔火功能不只是来自于植物叶片间可燃性的差异,更多源于常绿阔叶树的树冠结构以及相对密植构成的独特林分。通过抑制带内地表可燃物的生长,实现对地表火的阻隔;在遭受树冠火袭击时,以其树冠较弱的可燃性和分层特性消减火势(强度),降低火蔓延过程中热量输运的效率,使火蔓延自动终止。与传统的防火隔离带(生土带)相比,该项技术在阻挡火焰辐射、飞火以及保持水土和生态维护等方面拥有绝对优势。由于缺乏对其抵抗树冠火规模的量化认识,也没有建立起量化的技术性能指标以及细化的实施规范,生物防火林带技术仍处于经验型阶段。对该项技术的进一步发展与完善,不仅可以确保其在森林防火分隔实践中的应用效果,还可以在森林和城镇结合部等火灾多发地域发挥更大的作用。  相似文献   
66.
The impacts of elevated atmospheric CO2 concentrations (500 μmol·mol−1 and 700 μmol·mol−1) on total soil respiration and the contribution of root respiration ofPinus koraiensis seedlings were investigated from May to October in 2003 at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences, Jilin Province, China. After four growing seasons in top-open chambers exposed to elevated CO2, the total soil respiration and roots respiration ofPinus koraiensis seedlings were measured by a Li-6400-09 soil CO2 flux chamber. Three PVC cylinders in each chamber were inserted about 30 cm into the soil instantaneously to terminate the supply of current photosynthates from the tree canopy to roots for separating the root respiration from total soil respiration. Soil respirations both inside and outside of the cylinders were measured on June 16, August 20 and October 8, respectively. The results indicated that: there was a marked diurnal change in air temperature and soil temperature at depth of 5 cm on June 16, the maximum of soil temperature at depth of 5 cm lagged behind that of air temperature, no differences in temperature between treatments were found (P>0.05). The total soil respiration and soil respiration with roots severed showed strong diurnal and seasonal patterns. There was marked difference in total soil respiration and soil respiration with roots severed between treatments (P<0.01); Mean total soil respiration and contribution of root under different treatments were 3.26, 4.78 and 1.47 μmol·m−2·s−1, 11.5%, 43.1% and 27.9% on June 16, August 20 and October 8, respectively. Foundation item: This study was supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (KZCX1-SW-01) and the National Natural Science Foundation of China (30070158). Biography: LIU Ying (1976-), female, Ph. D. Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China. Responsible editor: Song Funan  相似文献   
67.
白千层组培苗移植技术研究   总被引:1,自引:0,他引:1  
林艺清 《林业调查规划》2010,35(6):116-118,123
运用正交试验设计研究组培瓶苗不同炼苗时间、不同基质和不同遮光率的遮阳网对白千层组培瓶苗移植成活率的影响及作用.结果表明,不同炼苗时间和不同基质配比以及不同遮光率的遮阳网对白千层组培瓶苗移植成活率有较显著影响,炼苗时间为15 d,基质采用泥炭土:红心土(3∶1),遮阳网遮光率为60%的设计组合效果最好,成活率达96.3%.  相似文献   
68.
    

Pine weevils (Hylobius spp.) feeding on stem bark of young conifer seedlings pose a serious threat to forest regeneration-planting programmes in Nordic countries. This study was designed to determine the threshold diameter for planted, untreated containerized seedlings, above which pine weevils cause little or no damage. The effects of sublethal weevil damage on seedling growth were also assessed. In total, 5320 containerized spruce seedlings were planted on scarified and unscarified plots on three sites in southern Sweden. Seedlings in six size classes, which differed with regard to age (1.5-3.5 yrs) and cultivation density (28-446 seedlings m 2) were grown using the Combicell system. None of the seedlings was treated with insecticides, except for those in the smallest class, where both untreated and treated seedlings were used. Inspections were made periodically during the first 3 yrs and after both 5 and 7 yrs. A statistically significant relationship was found between seedling losses due to pine weevil attack and seedling stem-base diameter at the time of planting out, on both scarified and unscarified plots. For seedlings with a stem-base diameter of around 10 mm, mortality due to pine weevil attack on scarified plots was low enough to be considered negligible. This threshold diameter was several millimetres greater for seedlings planted on unscarified plots. An analysis of the relationship between the extent of weevil damage and seedling growth rate showed that among surviving seedlings, those that grew fast tended to show low levels of damage. On unscarified plots, the mortality rate amongst seedlings treated once with a permethrin insecticide was only one-third that of untreated seedlings. On scarified plots, the corresponding difference was somewhat smaller. Repeated insecticide treatment resulted in a pronounced reduction in seedling mortality on the unscarified plots, whereas the effect was weaker on scarified plots.  相似文献   
69.
Dimorphandra jorgei MF Silva (Caesalpinaceae) and Swartzia macrostachya Benth. var. riedelii Cowan (Fabaceae) are tree species from the southern Bahian Atlantic Forest, identified for the restoration of degraded areas. The objective of this research is to study their seed germination and seedling growth to develop simple methods for seedling production in small scale nurseries. Because the species have distinct dormancy and germination characteristics, the seeds were submitted to different treatments. D. jorgei seeds were immersed in hot water, scarified and stored for 12 weeks in the laboratory environment (25°C). S. macrostachya seeds were submitted to different combinations of drying and storage in the laboratory environment or refrigerator (4°C). Seedlings were submitted to two light treatments for 3 months: partial shade (52% of full sun) and full shade (12% of full sun). In D. jorgei, the highest germination occurred for scarified seeds (87%) and for seeds stored for 12 weeks and then scarified (69%). In S. macrostachya the undried control seeds had the highest germination, followed by that of the refrigeration storage treatment, without predrying (99% and 97%, respectively). The average values for the growth parameters were greater in full shade for D. jorgei, while S. macrostachya seedlings showed greater growth rates in partial shade. Two months growth is recommended before D. jorgei seedlings are of the sufficient size and leaf number for field planting. On the other hand, a period of 4 months is recommended for S. macrostachya, due to its relatively slow growth.  相似文献   
70.
松皮小卷蛾幼虫空间分布型及其抽样技术的研究   总被引:1,自引:0,他引:1  
利用聚集度指标法对松皮小卷蛾幼虫的空间分布型进行了研究,结果表明,松皮小卷蛾幼虫为聚集分布’分布的基本成分是个体群,种群扩散为聚集扩散。根据Iwao的统计方法,利用N=1/D^2((α 1)/X β-1)公式,计算了各种虫口密度下的最适抽样数。  相似文献   
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