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1.
记述了采自广西壮族自治区十万大山的4个叶蜂新种:黑跗槌缘叶蜂PristiphoranigrotarsalinaWeisp.nov.、黑股昧潜叶蜂MetallusnigrofemoratusWeisp.nov.、黄斑平背叶蜂AllantusxanthomaculatusWeisp.nov.、南方黑毛三节叶蜂ArgesouthinaWeisp.nov..模式标本保存于中南林学院昆虫模式标本室.  相似文献   

2.
记述采自广西壮族自治区十万大山的4个蕨叶蜂科新种结铗平缝叶蜂Nesoselandria nodalisa Wei sp. nov.和黄肩侧齿叶蜂Neostromboceros xantholimus Wei sp. nov.,隶属于蕨叶蜂亚科(Selandriinae);大窝七节叶蜂 Heptamelus foveatus Wei sp. nov.,隶属于七节叶蜂亚科(Heptamelinae);黑角异齿叶蜂Niasnoca nigroflagella Wei sp. nov.,隶属于长背叶蜂亚科(Strongylogasterinae).模式标本保存于中南林学院昆虫模式标本室.  相似文献   

3.
本文记述了中国松叶蜂昆虫两新种,马尾松吉松叶蜂和油松吉松叶蜂。文中附有形态特征图4幅。  相似文献   

4.
报道了发现于河北省石家庄市灵寿县五岳寨旅游风景区的膜翅目Hymenoptera叶蜂科Tenthredinidae大基叶蜂亚科Belesesinae河北省一新记录种——黑尾大基叶蜂Beleses stigmaticalis(Cameron, 1876),并列出了中国境内大基叶蜂属Beleses Cameron, 1876已知种类名录。标本保存于华东药用植物园科研管理中心昆虫模式标本室。  相似文献   

5.
记述了采自四川的钩瓣叶蜂属3新种:九寨钩瓣叶蜂Macrophya jiuzhaina Chen et Wei, sp. nov.,乐怡钩瓣叶蜂Macrophya leyii Chen et Wei, sp. nov.,细瓣钩瓣叶蜂Macrophya parviserrula Chen et Wei, sp. nov..模式标本保存于中南林学院昆虫模式标本室.  相似文献   

6.
报道了发现于河北省石家庄市灵寿县五岳寨旅游风景区的膜翅目Hymenoptera叶蜂科Tenthredinidae叶蜂亚科Tenthredininae河北省3个新记录种——窄带横斑叶蜂Tenthredo parapompilina Wei&Nie, 1999、断突平斑叶蜂Tenthredo xanthotarsis Cameron,1876和圆斑纤腹叶蜂Tenthredo jozana (Matsumura, 1912)。标本保存于华东药用植物园科研管理中心昆虫模式标本室。  相似文献   

7.
报道了中国蕨叶蜂科蕨叶蜂亚科两新属新种:吴氏狭眶叶蜂Linorbita wuae gen.et sp.nov.和黑跗痕缝叶蜂Parapeptamena nigritarsis gen.et sp.nov.  相似文献   

8.
报道了2022年4—6月在浙江叶蜂区系调查时在百山祖国家公园发现的中国叶蜂科Tenthredinidae叶蜂属Tenthredo突刃槌腹叶蜂种团Tenthredo fortunei group一新记录种——林氏槌腹叶蜂Tenthredo lini Wei&Nie, 2003。该种主要集中在浙江的西南部区域,从中国地理分布状况来看,浙江的丽水一带有可能是该物种分布的最北缘地带。标本保存于华东药用植物园科研管理中心昆虫模式标本室[原丽水市林业科学研究院(原LSAF)]。  相似文献   

9.
整理采自甘肃膜翅目叶蜂科实叶蜂亚科、突瓣叶蜂亚科标本总计181号,经鉴定分为15属31种。其中,实叶蜂亚科6属9种:单室叶蜂属1种、狭脉叶蜂属1种、齿实叶蜂属1种、实叶蜂属1种、简栉叶蜂属2种、拟栉叶蜂属3种;突瓣叶蜂亚科9属22种:中脉叶蜂属2种、消缝叶蜂属1种、槌缘叶蜂属7种、厚爪叶蜂属1种、突瓣叶蜂属6种、蜷叶蜂属1种、枝角叶蜂属1种、瘿叶蜂属2种、吕氏叶蜂属1种。包括2甘肃新记录属:单室叶蜂属、狭脉叶蜂属;建立1新属:齿实叶蜂属;14科学新种:齿实叶蜂、甘肃梨实蜂、甘肃简栉叶蜂、截鞘中脉叶蜂、白唇消缝叶蜂、窄踵槌缘叶蜂、角斑槌缘叶蜂、痕脉槌缘叶蜂、短刺槌缘叶蜂、反刻突瓣叶蜂、白氏突瓣叶蜂、红股突瓣叶蜂、武氏瘿叶蜂、尖鞘瘿叶蜂;8甘肃新记录种和10已知种。  相似文献   

10.
记述中国西部地区叶蜂科突瓣叶蜂亚科两个新属新种:美丽任脉叶蜂Remonervaformosagen.et.sp.nov.,中华吕氏叶蜂Lueasinicagen.etsp.nov.任脉叶蜂属隶属于中脉叶蜂族Mesoneurini,但复眼微小,间距宽于复眼高2.5倍,颚眼距远宽于单眼直径,上颚Nematus型,唇基短,触角长于虫体,端部尖细,后头强烈延长,额脊发达,胸腹侧片脊状隆起,中胸侧板十分粗糙,前翅且2r脉,2Rs显著短于1Rs室,2A+3A直,后翅臀柄长,与cu-a脉垂直,爪内齿微长于并显著宽于外齿,锯腹片简单等,与同族已知各属均显著不同,吕氏叶蜂属界于突瓣叶蜂族Nematini和开臀叶蜂族Pseudodineurini之间,但上颚Nematus型,颚眼距宽于单眼直径,颜面微弱隆出,内眶不强烈陷入,前单眼位于复眼后缘连线上,口器短,下颚须长,前翅无2r脉,2A+3A直,第1肘横脉缺失,后翅R1室仅在端部开放,臀室端部开放或模糊,爪简单,锯胶片具叶状粗刺等,与此二族已知各属均不同,模式标本保存于中南林学院昆虫标本室.  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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