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1.
本文通过开展林下仿野生段木栽培灵芝试验,测定了灵芝连续年产量,比较了不同段木树种、不同林分对灵芝产量的影响,并对林下仿野生栽培和大棚栽培灵芝的品质进行了比较.结果表明:(1)林下段木仿野生栽培灵芝,能连续采收5年(菌段质量7~8 kg),每年可采收2次,其中第2年产量最高,随后逐年降低,前3年产量约占总产量的76%,1...  相似文献   

2.
文章以9种当地阔叶树种为研究对象,挑选同一林分阔叶树种枝丫材,经劈切捆成直径15cm和高20cm的接菌培养木段,接种发菌后,扣塑料棚进行地栽出芝,结果表明9种不同树种的木段均能出芝,但产量表现出较大的差异,不同树种对灵芝子实体和孢子粉产量由高至低的排序为千金榆、蒙古栎、柠劲子槭、最高,色木槭、假色槭、白榆其次,紫椴、白桦、核桃楸最低。试验结果为从事灵芝栽培产业选择适宜的树种木段接菌料提供依据。  相似文献   

3.
1 段木准备1.1 树种 栽培香菇的主要树种为柞树。其次有榆树,色木,白牛槭,水曲柳,胡桃楸及黑桦。1.2 选择菇木的标准 ①直径在8~20cm的原木。枝桠及树头均可;②生长在阳坡的树木比阴坡的树木产量高。1.3 菇木的采伐季节 以树木处于休眠状态时为最佳,一般应掌握在“冬至”后至翌年“立  相似文献   

4.
为筛选出适应吉林省西部盐碱区域栽培的绿化树种,本试验模拟东北地区苏打盐碱土成分对色木槭、白牛槭、拧筋槭三个树种进行盐碱胁迫试验。结果表明:中盐处理中,拧筋槭生长受抑制最小,耐盐碱能力明显好于色木槭和白牛槭;高盐胁迫中,拧筋槭抗性较强,色木槭和白牛槭抗性较弱。槭树科3树种耐盐碱能力排序由强到弱为:拧筋槭、白牛槭、色木槭。  相似文献   

5.
茶条槭、白牛槭、假色槭、拧筋槭等野生秋季红叶树种是牡丹江地区当前很受欢迎的景观树种。由于其发芽率低、发芽困难,致使育苗产量和质量受到很大影响。进行了牡丹江地区主要秋季野生红叶树种槭树的引种栽培研究,通过在学院实训基地对上述树种进行引种栽培试验,解决了其在牡丹江地区栽培的限制因子,降低了苗木生产成本,提高了苗木的质量和抗性,使其可以在本地区大面积推广和应用。  相似文献   

6.
阐述了槭树在园林上的应用价值,概述了槭树在世界和我国的引种栽培,详细地介绍了黑龙江省森林植物园的5种优良的槭树树种 :白牛槭、拧筋槭、色木槭、羽叶槭以及银槭.讨论了糖槭在利用方式上的改变.  相似文献   

7.
由浙江省林业科学研究院主持,丽水市食用菌研究开发中心、浙江大学、景宁县科委、嘉兴天源保健品有限公司等协作承担的浙江省“九·五”重大攻关项目“香菇栽培基质资源开发利用”,经浙江省科技厅批准,于 2002 年 8 月 24 日通过成果鉴定。该项目通过对 29 个树种的多点人工造林和不同树种木屑栽培试验,根据生物产量、萌芽力和香菇产量、质量等多个指标,综合评选出银荆、南酸枣、秃瓣杜英等 11 个适于短轮伐期的优良菇木树种,并深入研究了各树种的繁育技术、造林技术、矮林经营技术、合理轮伐期等配套经营技术。在节木栽培基质上生物…  相似文献   

8.
测定了山杨、大青杨等8个阔叶树种树皮和枯落物绝对含水率和相对含水率,依据含水率做了防火性能的排序,分析和评价了各树种的防火特性。结果表明,各树种枯落物的含水率由高至低的排序为山杨大青杨水曲柳胡桃楸蒙古栎黄波椤色木槭白桦;不同树种树皮含水率由高至低的排序为大青杨山杨胡桃楸水曲柳色木槭黄波椤蒙古栎白桦。  相似文献   

9.
采用18个树种袋料进行栽培香菇对比试验结果表明,不同树种袋料对香菇产量有显著的影响,其中以马褂木、南酸枣、拟赤杨的产量最高,枫香、桤木、胡枝子次之,而传统菇木树种甜槠、锥栗等产量一般,苦槠量差。  相似文献   

10.
近几年,灵芝栽培在我省东部林区迅速发展,给当地经济发展注入了活力,尤其为林场职工的脱贫致富提供了一个极好的机遇。短木段栽培灵芝的技术日臻完善.但不小栽培者对灵芝生产工艺流程中埋段这一环节存在歧意。有的欲采取墙式栽培方法,有的欲采取割口不脱袋埋段,认为不脱袋易保持水分。笔者通过实践证买,只有脱袋覆土栽培是最好的方法。  相似文献   

11.

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.

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 > TithoniaEuphatorium > 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.
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   

15.

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   

16.

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   

17.

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   

18.
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   

19.
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   

20.
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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