徂徕山药用植物资源调查分析

经过4年的调查研究,报道了徂徕山共有野生药用植物127科383属608种。山东道地药材有25种。多年生草本类228种,占药用植物总数的37.5%;全草类、根及地下茎类、果实及种子类最多,分别占药用植物总数的36.68%、24.48%和22.04%。优势科主要有菊科、蔷薇科和豆科等。优势属主要有蓼属和蒿属等。提出保护和开发的具体建议。     

箬寮岘自然保护区药用植物资源及其多样性

经野外调查和资料整理已知箬寮岘自然保护区共有药用植物17科572属991种,分别占保护区植物资源科、属、种数的91．4％、72．9％、56．6％;其中国家级珍稀濒危保护药用植物9种,占国家珍稀濒危保护药用植物的5．36％;全草类和根及根状茎类药用植物较多,分别占38．85％、34．11％;清热类、祛湿类和活血类药用植物较多,分别占41．98％、16．35％、11．00％。温带性属(43．76％)和热带性属(40．10％)所占比例大体相当。优势科主要有豆科、菊科、蔷薇科、唇形科、蓼科。     

广东省从化市野生珍稀濒危植物观赏特性评价及其开发利用

根据有关资料和调查统计,广东省从化市共有野生珍稀濒危植物12科12属12种(占广东省野生珍稀濒危植物总数的16%),其中裸子植物2科2属2种,被子植物10科10属1O种;渐危7种、稀有5种;观花类8种,观果(种)类11种,观叶类4种,观姿类8种。文章在分析这些野生珍稀濒危植物的观赏特性的基础上,还对其保护、开发利用进行了探讨。     

云龙天池国家级自然保护区野生观赏植物资源调查研究

对云龙天池国家级自然保护区168科477属1 118种维管植物进行观赏性调查分析。结果表明,保护区内共有野生观赏植物94科208属342种,其中木本植物191种,草本植物151种。野生观赏植物中优势科包括杜鹃花科、蔷薇科,龙胆科、兰科和毛茛科。观花、观叶、观果和观姿态这几类植物分别占观赏植物总数的59.36%、22.22%、10.53%和7.89%。在园林应用上包括盆景类、花灌木类、花坛花镜和花丛类,分别占观赏植物总数的20.47%、16.96%、14.62%和12.87%。珍稀野生观赏植物5科7属9种,分别占区内野生珍稀濒危植物的55.56%、63.64%和64.29%。文中对保护区在野生植物资源的保护与利用前景方面进行了探讨。     

安徽省潜山县珍稀濒危药用植物资源调查

通过对潜山县药用植物资源调查,发现珍稀濒危药用植物21种,共18科19属,其中珍稀濒危药用植物12种,国家重点保护野生植物12种,国家重点保护野生药材物种10种。对潜山珍稀濒危药用植物的种类、生态分布、资源及药用价值进行了介绍。     

甘肃白龙江林区野生花卉资源及多样性

经过多年的调查研究,甘肃白龙江林区野生花卉共有82科205属380种,其中木本植物301种,占总数的79.21%,草本植物79种,占总数的20.79%;珍稀野生花卉55科122属156种,占全国已公开记载珍稀野生花卉总数的23.39%,其中国家重点保护的珍稀野生花卉18科32属45种;野生花卉的优势科为蔷薇科、忍冬科和杜鹃花科,优势属为忍冬属和杜鹃花属;以落叶阔叶混交林带分布最多,其次为常绿阔叶混交林带;科的分布以泛热带分布、北温带分布为主;属的分布以北温带分布为主,其次为泛热带分布和东亚分布;其观赏特性以观花类、观果类和观叶类居多,分别占总种数的49.2%、28.16%、18.16%;园林用途以花灌木类、盆景类和园景类为主,分别占总种数的22.89%、19.74%、15.26%;并提出了具体的保护和利用建议。     

石湖省级自然保护区药用植物资源及其多样性研究

经过3a的调查研究，首次报道了石湖省级自然保护区共有药用植物89科、244属、355种，分别占保护区植物资源科、属、种数的91．75％，74．62％，60．27％。其中国家级珍稀濒危保护药用植物13种，占国家珍稀濒危保护药用植物的7．74％，吉林省重点保护药用植物47种，国家第一批保护药材8种，东北道地药材13种。全株和根及根茎类的药用植物最多，分别占39．72％，23．10％，12．39％；清热类和祛风湿类最多，分别占32、39％和15．49％。98．03％的种类分布在海拔700～1000m红松针阔混交林中，42.86％的种类属北温带分布区类型，优势科主要有菊科、蔷薇科、毛茛科、百合科等。文中还提出了保护与开发的具体建议。     

长白山区维管植物资源及其多样性

经过7年的调查研究发现,长白山区共有野生维管植物143科、629属、1 800种、190变种、47变型,分别占中国维管植物科、属、种数的47.67%,18.46%,5.80%.其中珍稀濒危植物25种,占植物总数的1.39%;多年生草本1 251种,占植物总数的69.5%;药用类、观赏和饲用类最多,分别占植物总数的51.56%、44.78%和33.67%.87.28%的种类分布在海拔450～1 000 m的红松针阔混交林中.提出保护和开发利用的具体建议.     

丹东地区野生药用植物资源多样性分析

对丹东地区野生药用植物资源进行了调查分析。结果表明,丹东地区野生药用植物共有126科407属794种,分别占中国药用植物科、属、种的34%、18%和7%,其中双子叶植物666种,占本区药用植物84%;多年生草本药用植物487种,占61%;全草/全株类、根(根皮)及根茎类和果实/种子类药用植物分别占51%、43%和14%;优势科主要为菊科、毛茛科、蔷薇科和唇形科;优势属为蓼属、堇菜属和乌头属,调查结果为本地区药用植物资源的合理开发利用提供了依据。     

西藏米林县药用植物资源

于2013-2015年采取样方调查、路线调查以及查阅文献资料等方法,对西藏米林县野生药用植物资源进行调查和多样性特征分析。结果表明,米林县共有药用植物资源77科225属316种,分别占本区维管植物科、属和种总数的84.62%,72.82%,58.30%;多年生草本植物占优势,共有183种,占本区药用植物总种数的57.91%;全草类药用植物最多,共有138种,占总数的43.67%;清热药类占多数,共有119种,占总数的37.66%;民族药用植物62科172属229种,占米林县药用植物总种数的72.47%。调查表明,米林县野生药用植物资源十分丰富,在入药部位、生长型、药效等方面具有较高的多样性。本文提出了建立野生药用植物资源数据库、加大民族药用植物研究、建立药用植物保护区的保护与发展建议。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

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.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

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.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

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.     

Growth of Phlebiopsis gigantea in wood of seven conifer species

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.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

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.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

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.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

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.     

CAD与建筑设计的关系

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。     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

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.     

Modelling of adequate pretwist for obtaining straight timber

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.