全国重点保护野生植物资源现状及保护策略

查清野生植物资源的种群数量及生存状况是植物多样性保护的基础。《中华人民共和国野生植物保护条例》中明确指出，野生植物行政主管部门应当定期组织国家重点保护野生植物和地方重点保护野生植物资源调查，建立资源档案。为此，我国于2012年启动第二次全国重点保护野生植物资源调查。基于此次调查数据，介绍了283种我国重点保护野生植物的种群数量、群落面积、就地保护状况等，并通过与第一次全国重点保护野生植物资源调查数据的对比分析，讨论了近十年野生植物资源变化的原因。从建立野生植物资源监管平台、完善植物多样性保护体系、开展野生植物拯救保护工程建设等方面提出整体提升我国野生植物保护管理水平的对策建议。     

我国野生植物保护的现状和前景

我国野生植物保护事业取得了长足发展，逐步扭转了野生植物资源急剧减少的趋势，保护和抢救了一批珍稀濒危物种；但是，我国的野生种质资源保护处于初级阶段，保护体系尚不完善，缺少整体布局和规划，在保护管理工作中遇到许多问题和困难，野生植物保护现状不容乐观。针对野生植物的资源特点，保护管理工作中存在的弊端，对野生植物保护管理工作实行大胆改革，积极创造条件开发一些消耗资源少且经济价值高的门路，发挥野生植物资源的经济价值，达到可持续利用的目的。     

野生植物资源管理的经济手段研究

目前我国对野生植物资源的保护和管理常采用行政手段，由于其存在高成本、低效率等问题，管理效果常常不尽人意．根据我国野生植物资源管理中存在的问题，提出将经济手段引入野生植物资源管理中，行政手段和经济手段相结合，有利于对野生植物资源的有效管理．文章阐述了野生植物资源管理中的税费手段、价格手段、交易制度和其他经济手段以及经济手段的实践．并提出明晰产权、完善资源税收机制、实行拍卖制度和野生植物资源有偿使用以及建立野生植物保护基金等建议．     

浙江自然保护区国家重点保护野生植物及其保护与利用

浙江自然保护区是浙江省国家重点保护野生植物集中分布的地区，共有国家重点保护野生植物21科30属34种，其中属I级保护7种，Ⅱ级保护27种，论述了自然保护区国家重点保护野生植物的区系特点、类型及地理分布，列举了它们的一些利用价值，最后提出国家重点保护野生植物保护的一系列建议。     

中华人民共和国野生植物保护条例

第一章总则第一条为了保护、发展和合理利用野生植物资源，保护生物多样性，维护生态平衡，制定本条例。第二条在中华人民共和国境内从事野生植物的保护、发展和利用活动，必须遵守本条例。本条例所保护的野生植物，是指原生地天然生长的珍贵植物和原生地天然生长并具有重要经济、科学研究、文化价值的濒危、稀有植物。药用野生植物和城市园林、自然保护区、风景名胜区内的野生植物的保护，同时适用有关法律、行政法规。第三令国家对野生植物资源实行加强保护、积极发展、合理利用的方针。第四条国家保护依法开发利用和经营管理野生植物资源…     

全国野生植物资源摸清了

记者从国家林业局获悉，历时8年的全国重点保护野生植物资源调查近日结束。此次调查全面摸清了分布于全国各地的189种野生植物的数量、分布、生境质量、濒危程度等基本状况，是建国以来首次全国范围内多种类的、以数量化为主要特征的大规模野生植物资源调查工作，为野生植物保护管理工作提供了科学依据。     

中华人民共和国野生植物保护条例

第一章总则第一条为了保护、发展和合理利用野生植物资源，保护生物多样性，维护生态平衡，制定本条例。第二条在中华人民共和国境内从事野生植物的保护、发展和利用活动，必须遵守本条例．本条例所保护的野生植物，是指原生地天然生长的珍贵植物和原生地天然生长并具有重要经济、科学研究、文化价值的繁危、稀有《物。药用野生植物和城市园林、自然保护区、风五名胜区内的巴生植物的保护，同时适用有关法律、行政法规。第三条国家对野生植物资源实行加强保护、积极发展、合理利用的方针。第四条国家保护依法开发利用和经营管理野生植物资球…     

怒江州全国重点保护野生植物资源现状及其保护对策

怒江州野生植物种类繁多，是云南省野生植物保护和管理的重点地区之一。怒江州全国重点保护野生植物资源调查，对列入调查的20种目的物种进行全州范围内的实地蹯查，基本掌握其资源现状和地理分布情况，通过对资源现状和致危因子的分析，对如何有效保护管理野生植物资源提出了相关的建议。     

昭通市野生植物资源的保护与利用研究

在对昭通市国家Ⅰ、Ⅱ级重点保护野生植物资源现状调查的基础上，系统分析造成野生植物物种资源濒危和绝灭的影响因素和存在问题，并研究提出野生植物资源保护与开发利用的对策措施。     

广西极小种群野生植物名录（上）

2012年6月11日，《广西极小种群野生植物拯救保护项目实施方案》在南宁通过评审。据最新统计，目前广西有极小种群野生植物32种，占全国极小种群120种的1／4。极小种群野生植物包括三类：野外种群数量极小、极度濒危、随时有灭绝危险的野生植物，生境要求独特、生态幅狭窄的野生植物，     

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.     

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.     

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.     

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.     

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。