佛顶山自然保护区药用种子植物研究

佛顶山自然保护区种子植物157科489属1069种，其中药用种子植物116科376属619种。本文从佛顶山自然保护区的药用种子植物区系特征、药用植物组成、功效、分布规律进行了研究，建设性地提出了科学开发和保护的建议。     

浙江凤阳山自然保护区的藓类植物资源

浙江凤阳山自然保护区自然生态系统保存良好,地质、土壤、气候等很适合藓类植物的生长和分布,通过调查发现,凤阳山有藓类植物32科80属131种。     

广西大王岭风景区野生药用维管植物初探

采取野外考察、标本采集、分类鉴定和资料考证等方法,对大王岭风景区药用维管植物资源进行了初步调查。结果表明:大王岭风景区现有药用维管植物共123科338种(含变种),其中蕨类药用植物24科37种,被子植物99科301种(其中双子叶药用植物有83科251种,单子叶药用植物有16科50种)。其中有何首乌、天冬等9种贵细药用植物,有桫椤等4种珍稀濒危药用植物。整理出大王岭野生药用维管植物名录。并对大王岭风景区药用维管植物资源的保护及开发利用进行了探讨。     

安徽岭南自然保护区的药用观赏蕨类植物资源

介绍了安徽岭南自然保护区药用观赏蕨类植物的种类、生境、药用部位、功效及观赏价值,并提出了开发利用的建议。     

河北省小五台山自然保护区药用山野菜资源及开发利用

该文对小五台山自然保护区野生药用山野菜资源进行了系统研究 ,并结合市场、自身现状和发展方向进行了重点分析 ,提出了开发利用的意义和建议     

大盘山石生藓类植物及其分布与环境因素的典范对应分析

采用样方法调查了浙江中部大盘山国家级自然保护区石生环境33个样点152个样方的藓类植物及其环境因子,并应用典范对应分析探讨了影响该地区石生藓类分布的主要环境因素.结果发现:(1)33个样点共记录有75种石生藓类植物;其中,丛藓科Pottiaceae、青藓科Brachytheciaceae、提灯藓科Mniaceae和灰藓科Hypnaceae为4个大科,含的种数分别为7、6、5和12种.含种数较多的属为灰藓属Hypnum、凤尾藓属Fissidens和青藓屑Brachythecium,分别含有5、4和5种;(2)海拔高度、水分条件和光照强度是影响大盘山地区石生藓类分布的主要环境因素;分析表明,海拔决定藓类植被的类型,进而影响光照、岩表温度和水分条件;石面光洁度对石生藓类分布也有一定的影响,而石面坡度与其分布没有显著的相关性.     

薯蓣植物组织培养研究进展

薯蓣科植物是一类极其重要的经济作物 ,可作食用、药用和工业原料。其中30多种药用薯蓣体内含有薯蓣皂素 ,是合成甾体激素类药物的重要原料。本文对薯蓣植物器官、组织、细胞培养领域的研究进展做了概述     

湖南小溪国家级自然保护区野生药用植物资源研究

对小溪国家级自然保护区的野生药用植物资源进行了初步调查。结果表明，小溪自然保护区有野生药用植物200科685属1420种。在介绍了88个科106种重要的药用植物药用部位和药用功能的基础上，就如何开发利用和保护药用植物资源提出了建议。     

秦皇岛市野生药用盐生植物资源调查

为了解秦皇岛市的野生药用盐生植物资源,通过大量的野外调查和室内鉴定,对其进行了详细的调查分析。结果表明:该市现有野生药用盐生植物108种,隶属38科、80属,其中双子叶植物占优势,有31科、69属、98种,分别占各自植物总数的81.58%、88.46%、90.74%,单子叶植物有7科、9属、10种,分别占各自植物总数的18.42%、11.54%、9.26%;该市野生药用盐生植物的优势科是菊科,其所含种数有16种,占总种数的14.81%;在秦皇岛市的108种野生药用盐生植物中,草本植物共有99种,占总种数的91.7%;灌木及半灌木有9种,占总种数的8.3%。文中还对该市资源丰富、具有开发潜力和濒临灭绝的野生药用盐生植物资源的生物学特性及药用价值作了详细的介绍,并就此类植物资源的开发利用问题进行了探讨。     

内蒙古大兴安岭主要野生药用真菌类植物

文章介绍了几种内蒙古大兴安岭林区野生药用真菌植物,药用真菌是天然药物的佳品,开发利用为人类服务。     

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.     

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。     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Key Habitats in the Norwegian Production Forest: A Case Study

This study investigated the forest history, structural characteristics, the presence of fungal species suggested to indicate ecological continuity in old-growth forest, and the species composition of saproxylic beetles in 30 old forest ''woodland key habitats'' (WKHs), and compared them with production forest in the same age-class in south-eastern Norway. No statistically significant differences in forest characteristics, community of saproxylic beetles or number of red-listed beetles were found between the WKHs and the production forest, probably owing to a combination of profound long-term logging and a lack of will to delineate sufficiently large WKHs in the one area with significantly less forestry impact. The study indicates the advantage of including forest history information in WKH selection where such data exist, and the importance of restoring habitats in heavily exploited forest landscapes.