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1.
含笑、木莲引种育苗试验 总被引：4，自引：0，他引：4
对木兰科深山含笑、乐昌含笑、金叶含笑、峨眉含笑,桂南木莲、红花木莲、乳源木莲等树种引种育苗试验结果表明,采取"浸种消毒,温室砂床催芽,芽苗移植,容器育苗,上方遮荫保湿,适时防治幼苗病害,喷施磷钾肥液增强苗木抗寒力"等技术措施,可使当年生苗木生长健壮,安全越夏越冬。其苗木生长:含笑属树种>木莲属树种;峨眉含笑>乐昌含笑>深山含笑>金叶含笑;乳源木莲>红花木莲>桂南木莲;同一种含笑,湖南种源>江西种源。苗木寒害(-5～-6℃):木莲属树种<含笑属树种;金叶含笑<深山含笑<乐昌含笑<峨眉含笑;桂南木莲<红花木莲<乳源木莲;同一种含笑,江西种源>湖南种源。 相似文献
2.
含笑、木莲属树种生态复合拟生栽培试验 总被引：5，自引：2，他引：3
在江苏省苏南低山丘陵南京、无锡地区引种木兰科常绿阔叶树(含笑、木莲),根据其引进树种的生物学特性、生态习性,针对幼龄期怕高温日灼,需荫蔽、温湿条件的特性,采用景观绿化树种金丝垂柳、无患子、黄山栾树、马褂木等进行了生态复合混交配置拟生栽培。因伴生树种的侧方遮荫作用,显著改善了下层含笑、木莲苗木生长空间的小气候条件,形成了幼龄适生的生态环境,保障了苗木免遭高温日灼危害,促进了苗木速生。研究结果为异地引种木兰科常绿阔叶树,培育含笑、木莲绿化苗木提供了适宜的栽培模式。 相似文献
3.
10个木兰科树种北移引种试验初报 总被引：3，自引：0，他引：3
对10种木兰科树种进行北移引种试验,比较不同树种在我国北亚热带和暖温带过渡地区河南省西南部的适应性及引种潜力。采用1～2 a生容器苗和地栽苗移栽,按常规水肥管理,并观测苗期在极端气候条件下的旱害和冻害等适应性状指标。结果表明,除观光木外,其余都能适应河南西南部的气候条件,生长基本正常,部分树种已开花结果。在-3℃～-4℃气温下,观光木受冻率达100%,冻害指数为V级,苗木地上部分冻死。1年生红花木莲,由于苗较小,受冻率为5%～30%,冻害指数I～II级,部分叶片受害。在持续秋旱60天的极端干旱气候条件下,采用每天人工早晚浇水一次,引种成活的9种木兰科植物均具有较强的抗旱适应性,受害率不到1%,仅有极少数植株发生枯梢受害。 相似文献
4.
在北亚热带苏南丘陵地区无锡惠山森林公园坡地引种浙江杭州种源深山含笑、乐昌含笑试验表明,深山含笑、乐昌含笑能适应无锡气候和惠山森林公园山坡立地条件,正常生长发育。在与苹果幼树(4 m×6 m)行间混交条件下,5年生深山含笑平均树高达4.02 m,胸径6.15 cm,45%植株开花结实;乐昌含笑平均树高达4.15 m,胸径7.6 cm,已达绿化大苗标准。引种深山含笑、乐昌含笑除在-7℃下1~2年生苗有较轻度叶冻害外,3~5年生苗木未见明显冻害。 相似文献
5.
含笑种源引进及测定评价 总被引：4，自引：0，他引：4
在北亚热带宁镇丘陵地区和太湖孤山丘陵地区引种原产中亚热带丘陵山区5种含笑种源试验结果表明,幼龄期生长量乐昌含笑>金叶含笑>深山含笑>醉香含笑>阔瓣含笑;长沙种源苗期抗寒性深山含笑>乐昌含笑>醉香含笑;高温日灼抗性乐昌含笑>金叶含笑>阔瓣含笑>醉香含笑>深山含笑;对持续60d秋旱的抗性深山含笑>乐昌含笑>醉香含笑。除醉香含笑历年在-5℃条件下会产生明显冻害外,幼龄期供试其他各种含笑均能适应引种的气候及圃地立地条件,正常生长发育。在供试种源中,浙江杭州种源深山含笑和乐昌含笑生长较好,适应性强,是值得扩繁应用的优良种源。而醉香含笑适应性较差,不宜在宁镇丘陵地区引种。安徽黄山种源深山含笑长势较差,抗寒性、抗旱性较差,亦不宜继续引种。 相似文献
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9.
深山含笑引种苗期试验初报 总被引：18，自引：7，他引：11
育苗试验表明,原分布在中亚热带的深山含笑基本能适应北亚热带南京地区的气候,正常生长发育。其种子发芽出土、形成幼苗需要较高积温,在塑料薄膜棚内,约需４０ ｄ。苗期生长呈单峰“∧”字形,４～６ 月生长缓慢,生长量占全年１４－４ ％ ;７ ～９ 月速生,生长量占全年８１－６ ％ ;８ 月生长量呈现峰值,占全年３９－９ ％ ;１０ ～１１ 月生长趋于停滞。１ ａ 生苗高１１－５ ～２９－０ ｃｍ ,平均高２３－４ ｃｍ ;２ ａ生苗高６５ ～１０６ ｃｍ ,平均高９４－０ ｃｍ 。苗木不耐寒,在－ ４ ℃自然低温时,１ ａ 生苗寒害率达３０％ ,需采取防寒措施。叶面喷施硼、锌、锰、镁等微量元素和磷钾肥液,能显著促进生长,减轻寒害。苗木高生长与气温、日照、蒸发量关系密切,适当减少日照,降低蒸发,增温保湿是保障引种的关键。 相似文献
10.
五种木兰科树种栽培对比试验研究 总被引：1，自引：0，他引：1
以树种的单位面积保存株数、平均树高、平均胸径、平均冠幅和单位面积蓄积量作为监测因子,对福建省建瓯市小松镇上仰村引种的12年生巴东木莲、马褂木、红花木莲、金叶含笑、阔瓣含笑5种木兰科树种生长情况进行调查分析,结果表明:树高生长量由高到低排列顺序为马褂木>金叶含笑>巴东木莲>阔瓣含笑>红花木莲;胸径生长量由高到低排列顺序为马褂木>金叶含笑>红花木莲>巴东木莲>阔瓣含笑;单位面积蓄积量由高到低排列顺序为马褂木>金叶含笑>巴东木莲>阔瓣含笑>红花木莲。说明马褂木和金叶含笑较适合当地生长,其余树种应进一步开展引种栽培试验。 相似文献
11.
《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
12.
《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
13.
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
14.
《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
15.
《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
16.
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
17.
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
18.
《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
19.
《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
20.
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