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1.
松材线虫对数种针叶树的致病性   总被引:2,自引:0,他引:2  
过去人们一直认为,日本松材线虫的寄主仅限于松属的树木,但在 1978年高温干旱天气,发现也危害绿化树种雪松、欧洲云杉,这就有必要重新明确线虫的寄主范围.笔者就此问题进行了研究,认为该线虫对松属以外的数种针叶树亦有致病性.本文概要报道了这一研究成果.实验方法(一)供试树种 5—8年生,树高约1米的日本冷杉、库页冷杉、日本落叶松、鱼鳞松、欧洲云杉、日本五针松以及8年生、树高2米的雪松等7种.各种树供试株数:接种20株,对照2—7株.(二)供试材线虫 采用从接种羽化的  相似文献   

2.
芬兰Abo Akademi大学木材和造纸化学实验室的科学家S.WillfOr等最近分析了12种重要的工业制浆软材的逝材和心材中的多糖含量和组成。这12种制浆软材分别来自欧洲云杉(挪威云杉)、白云杉、黑云杉、香脂冷杉、洛杉矶冷杉、西伯利亚冷杉、欧洲落叶松、美洲落叶松、北美短叶松、北美赤松(多脂松)、西方金钟柏(北美崖柏)、花旗松。  相似文献   

3.
通过对章古台沙地樟子松、赤松、油松等3种不同针叶树种天然更新对比试验,结果表明,3种针叶树1年生天然更新强度分别为3 594~5 133、20 300~50 000和8 300~13 900株.hm-2;赤松天然更新的强度好于油松,油松好于樟子松;樟子松天然更新1年生幼苗较难越冬,经覆盖后幼苗越冬成活率达66%;赤松、油松1年生幼苗相对较易越冬,越冬成活率分别为17.20%和20%,经覆盖后幼苗越冬成活率分别为54.94%和51.28%。因此,应采取人工促进措施进行樟子松、赤松、油松天然更新。  相似文献   

4.
针叶树引种育苗与造林技术研究简述   总被引:9,自引:6,他引:9  
中国三北 0 0 9项目办公室从 1990~ 1999年先后引种了 2 0种针叶树进行育苗造林试验。初步选出了班克松、长白松、沙地云杉和欧洲赤松等 4种针叶树可以在科尔沁沙地进行扩大造林 ;选出了青山、高峰等 6种樟子松优良地理种源。同时 ,引进推广了留床截根育苗和硬塑料容器育苗技术。试验认为 ,科尔沁沙地主要应该从北美洲半干旱半湿润地区引种针叶树 ;试验还认为 ,美国兰云杉、小干松、铅笔柏和洛基山园柏应该继续进行引种观察  相似文献   

5.
分别采用LX1-1、KR-134、S309和RF-C05 4种胶黏剂依次胶合欧洲云杉、欧洲赤松、兴安落叶松木材层板,制备成对应的结构用集成材。再依照GB/T26899—2011《结构用集成材》和GB/T 50005—2003《木结构设计规范》国家标准对制得的试样进行检测。实验结果表明,4种胶黏剂的胶合性能存在较大的差异:1)剥离率:4种胶黏剂在胶合欧洲云杉、赤松2种集成材时,浸渍剥离率均满足国标要求,但KR-134和RF-C05在第二次煮沸剥离率均未能满足国标。在胶合落叶松集成材时,LX1-1、KR-134在浸渍时剥离能满足国标要求,煮沸剥离未能满足国标要求,S309和RF-C05 2种剥离率均不满足国标。2)剪切强度和木破率:除S309落叶松集成材的湿剪强度和木破率均未能达到标准要求外,LX1-1、KR-134和RFC05胶合欧洲云杉、欧洲赤松和落叶松结构用集成材试样的湿剪强度均在3.9MPa以上,干剪强度均在5.9MPa以上,且木破率均大于75%,满足国标相关要求。3)LX1-1型异氰酸酯胶黏剂在胶合性能上优于其他3种胶黏剂,且兴安落叶松相比较其他2种木材,更加难以被胶粘。  相似文献   

6.
我区北疆冬季漫长,秋风叶落后,城镇面貌显得单调荒凉,几乎半年见不到绿色。如何迅速引种适应性强观赏性好的常绿针叶树种来绿化美化城市,是急待解决的问题。为了适应城镇绿化发展的需要,近几年来,我们进行了樟子松大苗、小苗移栽引种试验。 樟子松(PinusSylvestrisL.var.mongolicaLitv.)又名海拉尔松、蒙古赤松、西伯利亚赤松、欧洲赤松。是松科、松属的常绿乔木,是我国东北、内蒙古地区的主要森林组成的针叶用材树种。  相似文献   

7.
日本的森林面积为2,520万公顷,占全国面积的68%,其中天然林为1,620万公顷,人工林为700多万公顷,竹林约为20万公顷。全国有400多种珍贵的木本树种,如日本赤松、柳杉、扁柏、远东冷杉、鱼鳞松、日本落叶松、橡树、山毛榉、白蜡、杨树等。天然林中阔叶树种占优势,人工林中则相反,主要为针叶树种——柳杉、扁柏、日本落叶松、日本赤松、日本黑松、鱼鳞松和远东冷杉。  相似文献   

8.
[目的]通过对引种的云杉种和种源试验林的适应性和生长变异研究,选育出最适合当地栽培的优良种和种源。[方法]以甘肃省小陇山沙坝试验基地引种的欧洲云杉、黑云杉、白云杉、蓝云杉、红皮云杉和青海云杉6个树种20个种源为研究对象,分别对6、7、9 a幼林龄的生长性状(树高、地径、新梢和冠幅)进行方差分析和相关性分析,以早期评价云杉种和种源。[结果]6、7、9 a生长期内不同云杉种间和种源间的差异多数达到极显著,表明不同种间和种源间存在较大的遗传变异。利用树高兼地径为主要指标筛选出7个优良种源,分别为欧洲云杉加拿大AB01、AB03种源、白云杉加拿大GL01种源;黑云杉加拿大MA05、MA07、MA08和MA10种源,树高、地径现实增益均超过11%。欧洲云杉、白云杉种源树高与经纬度呈极显著的正相关,与海拔呈极显著的负相关;黑云杉种源树高也与经纬度呈极显著的正相关,但与海拔相关不显著。[结论]在原产地纬度49°16'~58°38'N,经度68°13'~118°24'W区域范围内引进欧洲云杉、白云杉、黑云杉种源,是适宜在甘肃小陇山栽培的云杉树种。  相似文献   

9.
长白松引种调查报告   总被引:2,自引:0,他引:2  
河北省山地树种单纯 ,作为用材和公益林的针叶树尤显贫乏 ,致使人工林组成不合理、林地生产力不高 ,社会生态效益难以充分发挥。要扭转这一局面 ,根本办法是进行乔灌木的树种改良 ,引种驯化则是重要途径之一。为此 ,我们从 2 0世纪 80年代开始 ,相继引进一批针叶树和治沙灌木 ,其中 ,长白松引种已达 1 7年 ,完成了种子繁殖、扦插育苗、荒山造林及开花结实的生长发育周期。1 产地与引种地的自然条件长白松 (美人松、长白赤松 )学名 P.sylvestriformis,产于吉林省长白山北坡海拔80 0~ 1 6 0 0 m山地 ,乔木 ,树高达 30 m,树干通直 ,光滑 ,树…  相似文献   

10.
从建筑应用和工业用材方面来说,松科、杉科、柏科的木材,是我国针叶树材3个重要的科。本文选择了松科的马尾松(Pinusmassoniana)、柔毛冷杉(Abies faxoniana),杉科的杉木(Cunninghamia lanceolata),柏科的柏木(Cupressus funebris),作为3科木材的代表,就其木材的显微构造特征方面进行比较。  相似文献   

11.
Over the last two centuries, logging has caused major, but unquantified, compositional and structural changes in the southern portion of the North American boreal forest. In this study, we used a series of old forest inventory maps coupled with a new dendrochronological approach for analyzing timber floating histories in order to document the long-term transformation (1820–2000) of a southern boreal landscape (117 000 ha) in eastern Quebec, Canada, in response to logging practices. Landscape exploitation became increasingly severe throughout this time period. During the ninetieth century (1820–1900) of limited industrial capacity, selective logging targeted pine and spruce trees and excluded balsam fir, a much abundant species of the forest landscape. Logging intensity increased during the first half of the twentieth century, and targeted all conifer species including balsam fir. After 1975, dramatic changes occurred over the landscape in relation to clear-cutting practices, plantations, and salvage logging, which promoted the proliferation of regenerating areas and extensive plantations of the previously uncommon black spruce. Overall, logging disturbance resulted in an inversion in the forest matrix, from conifer to mixed and deciduous, and from old to regenerating stands, thus creating significant consequences on forest sustainability. If biodiversity conservation and sustainable forestry are to be management goals in such a heavily exploited forested landscape, then restoration strategies should be implemented in order to stop the divergence of the forests from their preindustrial conditions.  相似文献   

12.
Summary This study compared the susceptibility of five UK‐grown conifer species to colonization by sapstain fungi in two trials carried out in consecutive years. The conifers consisted of Sitka spruce (Picea sitchensis), Japanese larch (Larix kaempferi), Norway spruce (Picea abies), Scots pine (Pinus sylvestris) and lodgepole pine (Pinus contorta). Freshly cut 1‐m logs were exposed to the available inoculum of sapstain fungi from April to August in a woodland environment in the south east of England. Logs of each species were removed after 1‐, 2‐ and 4‐month exposure and sampled destructively to assess the amount of sapstain. In the second trial, per cent moisture content and concentrations of nitrogen, carbohydrate and phenolic compounds in the sapwood were also measured at the start and end of the trial. After 2 months, only the sapwood of both pine species had significant levels of sapstain; mean values of 37% and 19% for lodgepole pine (year 1 and year 2 respectively) and 12% and 1% for Scots pine. After 4 months, the levels of sapstain in both pine species exceeded 60% in both years. By contrast, very little sapstain developed in the other conifer species with maximum mean values of 10% for Norway spruce, 3.5% for larch and less than 1% for Sitka spruce. Overall, the moisture content of the logs decreased progressively in all species over the length of the trial. However, pine logs tended to retain higher levels of moisture throughout the trial compared with spruce or larch. The relatively higher moisture content of pine sapwood may be closer to the optimal moisture content that sapstain fungi require for infection and colonization, thereby contributing to the increased susceptibility of pine compared with the other conifer species. The pine logs also suffered from some colonization by bark beetles (Ips sexdentatus), which increased the inoculum potential and the opportunity for colonization by sapstain fungi. In addition, particular phenolic compounds in conifer sapwood may play a role in determining the resistance of some species to sapstain. Notably the most resistant species, Sitka spruce, was the only softwood that still retained detectable levels of phenolics in the sapwood to the end of the trial.  相似文献   

13.
The Siberian moth, Dendrolimus sibiricus, Tschtv. is the most harmful defoliator of coniferous forests in North Asia. The pest has already spread over the Urals and continues moving westwards. Recently, it has been recommended for quarantine in member countries by European and Mediterranean Plant Protection Organization (EPPO). The performances of the pest on coniferous species planted in Europe were assessed on a range of potted trees corresponding to the spectrum of economically important conifers in the EU: European larch Larix decidua, Norway spruce Picea abies, Scots pine Pinus sylvestris, European black pine Pinus nigra, and the North American species: Douglas fir Pseudotsuga menziesii and grand fir Abies grandis. Larvae showed a potential to survive and complete the development on all these host tree species. Favorable hosts were grand fir, European larch, and Douglas fir that allowed higher survival, better larval development, and as a result, yielded heavier pupae and adult moths with higher longevity. Black pine was a poor host but, however, could still support larval and pupal development. Norway spruce and Scots pine had an intermediate behavior. If accidentally introduced to Europe, the Siberian moth may become especially damaging in forest stands predominated by European larch and by the North American firs. Norway spruce and especially the two-needle pines will be less prone to intensive defoliation by this species. The fact that the pest may damage the range of economically important coniferous species should be taken into account in the pest risk assessment for Europe and also for North America where the Siberian moth occurrence is considered likely.  相似文献   

14.
Abstract

Fungal root pathogens are widespread and may cause substantial seedling losses in conifer nurseries. Furthermore, poor seedling survival and growth on reforestation sites results in reduced forest regeneration. Use of microbial inoculants for disease control and plant growth promotion has become an important endeavour. A microbial culture collection of 500 strains was assessed for biological control of fungal root pathogens and/or plant growth promotion of conifer seedlings. Seven of these strains showed significant suppres-sive effects on various soil-bome fungal pathogens. On Douglas fir, two strains, RAL3 and 64-3, reduced disease caused by Fusariumby. 7-42% in repeated growth room assays. The same strains significantly increased healthy stand of white spruce seedlings inoculated with Fusariumand Pythiumin a conifer nursery, and increased the survival of bare-root white spruce seedlings planted on a reforestation site by 19-23%. Both strains also significantly increased new root and total plant dry weights. Strain RAL3 in commercial formulation maintained a viable population of about log 8-9 cfu/ml for over a year when stored at 5°C. Strain survival on seed varied with conifer species. No decreases in bacterial populations were observed on seeds of jack pine or Douglas fir after 37 to 44 days storage at 5°C, but decreases were observed on seeds of white spruce and Scots pine. This study has provided candidate beneficial microbial inocu-lants which offer promise for development of commercial inoculants for the forestry industry.  相似文献   

15.
Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) was first introduced to Europe from North America more than 150 years ago, was then planted on a large scale and is now the economically most important exotic tree species in European forests. This literature review summarizes the current knowledge on the effects of Douglas fir on soil chemistry, plants, arthropods and fungi. Douglas fir shapes its abiotic environment similarly to native tree species such as Norway spruce, silver fir or European beech. In general, many organisms have been shown to be able to live together with Douglas fir and in some cases even benefit from its presence. Although the number of species of the ground vegetation and that of arthropod communities is similar to those of native conifer species, fungal diversity is reduced by Douglas fir. Special microclimatic conditions in the crown of Douglas fir can lead to reduced arthropod densities during winter with possible negative consequences for birds. The ecological impacts of Douglas fir are in general not as severe as those of other exotic tree species, e.g., Pinus spp. in South Africa and Ailanthus altissima, Prunus serotina and Robinia pseudoacacia in Europe. Nonetheless, Douglas fir can negatively impact single groups of organisms or species and is now regenerating itself naturally in Europe. Although Douglas fir has not been the subject of large-scale outbreaks of pests in Europe so far, the further introduction of exotic organisms associated with Douglas fir in its native range could be more problematic than the introduction of Douglas fir itself.  相似文献   

16.
Butt rot in mixed conifer stands. 70 years old Pseudotsuga menziesii trees on sandy soil, grown together with Pinus syhestris, Picea abies, Fagus sylvatica were analysed for butt rot. 73 % resp. 70 % of the Douglas fir, 13% resp. 28% of the Scotch pine and 82% resp. 84% of the Norway spruce showed decay. The most frequent fungi in Pseudotsuga were Heterobasidion annosum, Calocera viscosa, Sparassis crispa, in Pinus Sparassis crispa and in Picea Heterobasidion annosum. In a neighbouring stand with 85 years old Pseudotsuga menziesii - more often thinned than the 70 years old stand - only 23 % of the trees were with decay.  相似文献   

17.
Vertical distribution of leaf area largely governs both tree structure and function. Models of this important tree attribute have been constructed for several commercially important conifers. However, a limited number of studies have compared alternative modeling techniques and inherent species differences. This study used several existing datasets for the five primary conifer species in Maine, namely balsam fir [Abies balsamea (L.) Mill.], northern white-cedar [Thuja occidentalis (L.)], eastern hemlock [Tsuga canadensis (L.) Carr.], eastern white pine [Pinus strobus (L.)], and red spruce [Picea rubens (Sarg.)] to examine species variation in total and vertical distribution of projected leaf area at the individual branch- and tree-levels. In addition, multiple methods for modeling the vertical distribution of leaf area were examined across the species. For a given branch diameter and location within the crown, eastern hemlock branches held the greatest amount of leaf area, followed by balsam fir, northern white-cedar, white pine, and red spruce. At the tree-level, eastern white pine held the greatest amount of leaf area followed by eastern hemlock, balsam fir, red spruce, and northern white-cedar for a given tree size. Across species, the two-parameter, right-truncated Weibull distribution performed the best for predicting vertical distribution of leaf area when compared to the four-parameter beta and Johnson's SB distributions (reduction of root mean square error of 1.7–21.1%). Northern white-cedar had a relative distribution of leaf area distinctly different than other species in this study with a mode shifted towards the upper crown. In contrast to red spruce and white pine, the mode of the relative distribution of leaf area for balsam fir and eastern hemlock occurred lower in the crown. Results of this study suggest that differences in total and vertical distribution of leaf area exist between species, but significant amounts of their variation are largely accounted for by bole and crown size.  相似文献   

18.
三峡地区高山乡土造林树种选择研究   总被引:2,自引:0,他引:2  
自上世纪70年代以来,大老岭林场开展了北亚热带三峡地区高山造林树种生态调查[1]。依据调查结果:1981年选择玉兰、银鹊、鹅掌秋、鄂枫杨、漆树、大叶杨、山桐子、桦榛、白辛、檫木、珙桐、香椿、亮叶桦、水曲柳等阔叶乡土树种和油松、华山松、落叶松、柳杉等针叶乡土树种开展栽培试验研究。通过各树种成活率、保存率及生长量26 a(2004)调查表明:26 a(2004)生现实遗传增益银鹊比11个阔叶树种材积提高26.8%,比其它10个阔叶树种材积提高32.0%;日本柳杉比4个针叶树种材积提高36.5%,比其它3个针叶树种材积提高48.8%。银鹊,日本柳杉最适宜三峡山区生长,营造银鹊、日本柳杉工业用材林,可大力提高新造林分生产力,现实遗传增益15%以上,取得较好的经济、社会和生态效益。  相似文献   

19.
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   

20.
Planting exotic conifers offers indigenous forest insects an opportunity to extend their host range and eventually to become significant pests. Knowing the ecological and evolutionary modalities driving the colonisation of exotic tree species by indigenous insects is thus of primary importance. We compared the bark beetle communities (Coleoptera: Curculionidae, Scolytinae) associated with both native and introduced conifers in France. The aim of our study was to estimate the influence of both host- and insect-related factors on the beetles’ likelihood to shift onto new hosts. We considered the influence of host origin (i.e. native vs. exotic), host tree species identity, tree bark thickness and tree taxonomic proximity, as well as insects’ host specificity. A field inventory using trap trees was carried out in two regions in France (Limousin and Jura) during two consecutive years (2006 and 2007) on three European native conifer species [Norway spruce (Picea abies); Scots pine (Pinus sylvestris) and European Silver-fir (Abies alba)] and five North American [Sitka spruce (Picea sitchensis); Eastern white pine (Pinus strobus); Grand fir (Abies grandis); Douglas fir (Pseudotsuga menziesii) and Western red cedar (Thuja plicata)]. A total of 18 indigenous and 2 exotic bark beetle species were collected. All exotic conifer species were colonised by indigenous bark beetle species and no significant difference was observed of the cumulated species richness of the latter between native and exotic tree species (13 vs. 14, P < 0.05). The ability of indigenous bark beetles to shift onto exotic conifers appeared to strongly depend on host species (significantly structuring bark beetle assemblages), the presence of phylogenetically related native conifer species and that of similar resources, in combination with insect host specificity. Host tree species status (native or exotic) also seemed to be involved, but its effect did not seem as essential as that of the previous factors. These findings are discussed in terms of adaptation, plasticity and practical aspects of forest management.  相似文献   

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