鲁东南滨海园林植物资源和耐盐性调查分析

在野外调查和文献查阅相结合的基础上,通过对鲁东南滨海植物的调查及绿化植物耐盐碱能力的分析研究,编制出鲁东南滨海地区野生植物名录,并根据植物生长状况和立地条件对园林绿化植物的耐盐碱能力进行分类,筛选出适合该区园林绿化的植物。调查结果表明:1)鲁东南滨海地区的绿化植物共61科174种,其中已用于园林绿化的植物37科83种,包括裸子植物3科8种,被子植物34科75种;野生植物31科91种;可大力推广的园林绿化植物47种。2)野生植物中可用于园林绿化的共5种,已用于园林绿化但鲁东南滨海没有引种的植物4种,还有1种濒危物种和2种外来入侵物种。     

秦皇岛滨海地区春季观花植物观赏特征分析

通过查阅文献及实地调研,对秦皇岛滨海地区春季观花植物进行调查与分析,结果表明:秦皇岛滨海地区园林应用的春季观花植物有73种,以观花灌木种类最多;应用频度超过80%的春季观花木本植物共12种,应用频度低于40%的有27种,园林开发应用潜力巨大;花期时序多集中在4月,春季植物景观效果最好;植物花色以红粉色系为主。通过对比秦皇岛滨海地区与北京地区春季观花植物及景观特点,从整体分区、分段配置、主配分明、乡土优先等方面对秦皇岛滨海地区春季观花植物景观营造进行了探讨。     

秦皇岛滨海地区夏季观花植物观赏特征分析

通过实地调研及查阅文献,对秦皇岛滨海地区夏季观花植物资源进行调查与分析。结果表明:秦皇岛滨海地区园林应用的夏季观花植物有62种,以地被植物种类最多;应用频度超过40%的夏季观花木本植物共14种,但乔木应用较少;花期时序多集中在6月,夏季植物景观7月整体效果最佳;植物花色以白色和蓝紫色为主。最后,对秦皇岛滨海地区夏季观花植物景观营造技术进行了讨论。     

秦皇岛滨海地区野生药用盐生植物园林应用研究

以秦皇岛滨海地区野生药用盐生植物资源调查为基础,对其中23种具有较高观赏价值、生态价值的植物观赏特性及园林应用形式进行分析,提出了利用野生药用盐生植物构建多层次稳定的植物景观,探讨了特色景观建设的几种模式,可为滨海特色景观建设和实现景观可持续发展提供参考.     

天津滨海湿地不同植物矿质元素的分布及迁移特征分析

滨海湿地位于海陆交错地带,属于典型的生态脆弱区。探究滨海湿地植物中矿质元素的分布及迁移特征,有助于正确认识和理解滨海湿地生物地球化学循环这一关键过程。本文以天津滨海地区7种常见的湿地植物作为研究对象,研究P、K、Na、Ca、Mg、Al、Fe、Cu、Sr、Zn、Mn、Cr等12种矿质元素在植物不同器官中的分布与迁移特征。结果表明：Ca、Mg、Al、Fe、P在植物叶片和根系中的含量显著高于Sr、Zn、Mn、Cr、Cu、K、Na等矿质元素,且不同植物之间矿质元素含量的差异多与其抗盐和磷吸收的能力有关。所有植物中,大蓟对矿质元素的吸收能力弱,但转移能力强,狗尾草则趋势相反。其它如柽柳、刺儿菜、碱蓬、青蒿、盐地碱蓬等植物对多种矿质元素的吸收和转移能力均较高。相关分析表明12种元素组成的66对元素中,仅有14对元素密切相关,矿质元素之间的这种耦合与拮抗关系与植物自身代谢和不同器官的需求有关。主成分分析结果表明12种矿质元素根据功能可大致划分为三个组合,而碱蓬与盐地碱蓬在盐离子的吸收和转移功能上与其他植物明显不同。     

天津滨海野生观赏盐生植物资源调查与园林应用

在野外调查和文献查阅相结合的基础上,对天津滨海野生盐生植物资源进行了调查与分析,筛选出40多种具有较高观赏价值的盐生植物,并对其园林观赏特性及园林应用形式进行深入分析,为滨海的景观建设奠定有利基础。     

广西北海涠洲岛植物资源调查研究

对涠洲岛上的植物资源进行调查研究,统计结果表明,该岛植物资源丰富,共有131种,隶属于77科121属,其中蕨类植物2科3属4种,裸子植物1科1属1种,被子植物74科117属126种。植物构成体现滨海特色、风水林文化特色等,大多数种类具有较高观赏价值和生态价值,对其生态特性及绿化应用进行分析,为滨海地区的绿化建设提供参考。     

大连长兴岛北滨海路绿化带植物结构特征研究

该文调查大连长兴岛北滨海路绿化带植物的种类和分布现状,采用物种重要性指数、物种重现率、物种多样性指数等分析其整体结构特征,并对长兴岛北滨海路绿化植物的配置和应用进行了讨论,为进一步优化滨海路绿化结构,提升植物景观的层次多样性和美观程度提供参考。     

黄河三角洲滨海盐碱地绿化植物资源普查及选择研究

以我国滨海盐碱地的典型代表之一——黄河三角洲为工作点,通过对该地区绿化植物的普查和统计,根据植物生长状况及其立地条件,对该区绿化植物的耐盐碱能力进行分析研究,编制出黄河三角洲野生植物名录和黄河三角洲园林植物耐盐碱性分类表。并在此基础上,考虑到黄河三角洲的土壤、水文特点及园林绿化的制约因素,结合已经实践证明能在该区良好生长的园林植物,分析研究野生植物及其在园林绿化上的应用,联系经济效益、生态效益、社会效益,提出滨海盐碱地绿化植物资源在不同条件下的最佳选择。     

广东省滨海乡土耐盐植物资源及园林应用研究

通过实地调查和文献查阅,对广东省滨海耐盐的乡土植物资源进行整理和总结。结果表明,广东省共有野生海岸耐盐植物240种,隶属84科,大多处于尚待开发状态;结合耐盐程度、适应性和观赏特点等各项指标评价,优选46种植物推荐应用于滨海景观带或防护林建设。分析广东省滨海绿化现状,提出海滨耐盐植物开发利用的建议,建立耐盐乡土植物专类苗圃,并为海滨绿化配置多层次多树种的群落结构。     

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

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.