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试谈把厦门建成“椰风海韵”的热带海滨城市的构想 总被引：9，自引：0，他引：9
根据棕榈科植物的生长特点、景观特色和应用价值,结合厦门的自然地理条件以及棕榈植物在厦门的引种驯化、景观配置的实践经验,按照厦门市绿化规划构想,提出并论证了大量应用原产热带海岛的棕榈植物以改造本岛植物景观,把厦门建成“椰风海韵”、特色明显的热带海滨城市的构想。 所谓特色,就是有明显的个性、独特的 相似文献
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棕榈科植物主要病虫害防治 总被引：6，自引：0，他引：6
棕榈科(Palmae)植物约有210属2800种,分布于热带、亚热带地区,主产热带亚洲及美洲,少数产于非洲。我国原产及引种栽培的共约250种,主要分布在云南、海南、广东、广西和福建等省地。 随着棕榈植物的广泛栽植,其病虫害种类及其危害的严重性也逐渐增加,成为棕榈栽培与管理中不可忽视的问题。现对发生严重的几类病虫害提出防治措施。 相似文献
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湖南杜鹃属植物种类及引种适应性初探 总被引：4，自引：0，他引：4
在对湖南杜鹃属植物的野外调查、资料收集、标本鉴定的基础上,对其在湖南省森林植物园的引种栽培适应性进行研究。湖南产杜鹃属植物57种1变种,隶属5亚属8组14亚组,其中映山红亚属数量最,多达21种,占36.21%;湖南省森林植物园引种保存湖南杜鹃属植物38种,其中杜鹃亚属2种、常绿杜鹃亚属11种、马银花亚属8种、羊踯躅亚属1种、映山红亚属16种。引种栽培效果表明:马银花亚属在引种栽培中适应性最强,8种均表现为优良;原生分布海拔低的物种适应性高于相对海拔高的物种。分析探讨湖南杜鹃属植物在长沙地区的适应性,提出杜鹃属植物异地保育和开发建议。 相似文献
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长林系列品种油茶籽含油率和脂肪酸组成分析研究 总被引：1，自引：0，他引：1
对10个引种栽培的长林品种油茶籽含油率和脂肪酸进行了测定.结果表明:采果时间对含油率影响大,不同品种间含油率差异显著.长林3号含油率比原产地高0.80％,长林4,18,23,27号引种后含油率与原产地差异不大,审定的长林3,4,18,23号和27号比对照分别大10.10％,4.65％,6.35％,11.63％和10.51％.油茶籽油脂肪酸主要由油酸、亚油酸、棕榈酸和硬脂酸4种脂肪酸组成.油酸含量在72.40％～84.70％,均值为79.34％;亚油酸含量在4.30％～15.50％,均值为9.47％;棕榈酸含量在6.60％～9.00％,均值为7.75％;硬脂酸含量在1.20％～3.10％,均值为2.03％. 相似文献
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2012—2018年采用典型地块、典型线路详查为主,全面踏查为辅的方式对宁波市杜鹃属植物资源进行调查。结果表明,宁波市共有野生及习见栽培的杜鹃属植物9种1变种1变型,其中野生种6种1变种1变型,习见栽培种4种。从水平分布看,有广域种、区域种、局域种和微域种4种类型;从垂直分布看,只分布于海拔700 m以上的有华顶杜鹃、白花满山红2种,分布于海拔400~700 m的有云锦杜鹃、羊踯躅2种,分布于海拔400 m以下的仅普陀杜鹃1种,而所有海拔均有分布的有映山红、满山红、马银花3种。与天目山、天台山、舟山群岛、浙江南部和大盘山等周邻区系相比,宁波的野生杜鹃物种资源多样性处于中等水平,相互之间既有共性,但也各具特色。建议开展杜鹃属植物资源的引种驯化,进一步丰富当地的景观植物资源,提高杜鹃属植物育种、资源利用和产业化水平。 相似文献
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云南的辣木引种试验初报 总被引：7，自引：0，他引：7
在云南的开远、东川、永仁、思茅、瑞丽5地进行了8个种源,2个品种的辣木引种试验,所引种的辣木其幼树期表现出生长迅速,能正常开花结实的状况;且所引种的10个种源(品种)间生长差异并不显著。辣木定植后,呈现持续生长的状态,无明显缓苗期;年生长态势在年内大部时间生长迅速,到11月初随着温度的下降而生长减缓,粗生长在后期增长明显加快。表明辣木生长受温度影响较为明显,对温度的变化较敏感。引种的辣木植株1年生枝耐修剪,显示其为易于更新的树种。另外,引种的辣木叶中蛋白含量与原产地基本相同,但钙、钾、镁等微量元素的含量低于原产地,而维生素含量则高于原产地。 相似文献
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棕榈科植物在厦门的引种栽培及其应用 总被引：5，自引：0，他引：5
从棕榈的幼树培育和移植后的管理等方面阐述了棕榈引种栽培的主要技术,并对它们在多方面的应用作了初步的总结,为该树种在厦门的引种栽培和科学管理以及园林绿化等方面提供参考。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
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Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and
also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the
amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter
bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K
was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed
significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed
during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly
between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species
provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient
enrichment capacity and slower decomposition rates which would minimize leaching losses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):118-130
The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions. 相似文献
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Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
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《Wood material science & engineering》2013,8(2):76-84
Abstract Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists. 相似文献
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Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
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本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献