四种蕨类的根茎繁殖技术

蕨Pteridium aquilinum(L.)Kuhn Var.latiusculum(Desv.) Underw.荚果蕨Matteuccia struthiopteris(L.)Todaro.多齿蹄盖蕨Athyrium m ultidentatum(Doell.)Ching 和分株紫萁Osrnunda Cjnnamomea L.Var.asiatica Fernala.是林区常见的4种蕨类山野菜,分布广、面积大、产量高,长期为林区居民食用。据史料记载,我国食用蕨的历史,至少已有两千多年。近年来作为商品,在国内市场正在兴起。一些城市的宾馆、餐厅,作为风味佳肴在宴席上深受宾客的欢迎。随着食物结构的变化,人们对保健和营养日益重视。4种蕨类山野菜作为蔬菜的新品种,在国际国内市场,将有极大潜力。     

四种蕨类繁殖叶及采集期比较

蕨菜、薇菜、荚果蕨、蹄盖蕨是黑龙江省四种主要出口蕨类,由于过度采收,产量逐年下降。现人工栽培基本是挖根茎栽培,采用孢子繁殖栽培极少,挖根茎虽扩大了种群但亦破坏了野生资源。对四种蕨类繁殖叶的特征、孢子成熟期及采集时间进行比较,以利对采用孢子繁殖栽培者参考。     

四种蕨类孢子生命力的研究

蕨菜(蕨)Pteridium apuilium(L.)Kuhn、薇菜(分株紫萁)Osmunda cinnamomea L.、猴腿(东北蹄盖蕨)Athyritum brevifrons Hakai和荚果蕨Matteuccia struthiopteris(L.)Todaro是我国广大林区常见的4种蕨类山野菜,食用历史悠久,现代人类更加大力开发,野生资源的质量越来越瘦,数量逐年减少,促使人们开始关注人工栽培,人工栽培中,繁殖技术分无性和有性两种,有性繁殖即孢子繁殖。孢子繁殖的成功与否,首先取决于孢子的生命力。为此,我们对采集来的孢子在不同贮藏条件下,进行了其生命力的研究。     

青蕨的繁育与栽培技术

青蕨,学名菜蕨(Callipteris esculenta),属于蹄盖蕨科多年生蕨类高等植物,分布于山区,生于山沟,山谷、小溪两旁,林下坡地湿地上.     

融水县主要野生蔬菜资源及开发利用研究

介绍了融水县野生蔬菜的基本情况,分析了融水县野生蔬菜资源开发利用现状、主要食用品种、食用部位及食用方法,并提出了存在问题及对策.     

野生蕨菜的人工驯化栽培技术

蕨菜,又名龙菜、蕨薹,属于凤尾蕨科的多年生草本植物,在管涔林区的山林草地间分布极为广泛。蕨菜因为新鲜可口,风味独特,营养丰富而为人们所喜食。近年来,食用绿色食品极为风行,而蕨菜因其生长在无污染的环境中,是极其优良的绿色食品品种,因而深受国际市场的欢迎。尽管蕨类资源在管涔林区较为丰富,但近年来由于对野生蕨菜的过度采集和人为活动对其生存环境的破坏,其产量逐年下降。因此,为了保护蕨菜资源,发展人工栽培技术显得十分必要。近两年来,我们对蕨菜的人工栽培技术进行了初步的研究试验,并掌握了一定的技术,现介绍如下。1蕨菜的生物…     

江西野生木本食用植物资源及其特点研究

江西野生木本食用植物资源丰富,种类繁多、分布广泛,在全省２０００多种野生木本植物中拥有食用种类近８００种,隶属７８科,１８６属。按其可供食用部分及其主要食用用途可归类成淀粉类、木糖类、果品类、油料类、菜用类、香料类和其他类７大类型。对野生木本食用植物资源的特点和植物的区系特征作了简要分析,并对资源的保护和合理开发利用提出了建议。     

九阜山杀虫抗菌蕨类植物资源调查初报

对福建省尤溪县九阜山省级自然保护区具有杀虫抗菌作用的蕨类植物资源进行调查,结果表明,该区可作为农药使用的野生蕨类植物共有21种,分属12科18属,主要集中在鳞毛蕨科(5种)、紫萁科(2种)、凤尾蕨科(2种)、乌毛蕨科(2种)、金星蕨科(2种),开发利用价值较大的种类有海金沙、紫萁、蕨、狗脊蕨、蜈蚣草、乌毛蕨、阔鳞鳞毛蕨等。介绍了每种杀虫抗菌蕨类植物的生境、主要化学成分、活性部位和作用方式,并提出开发利用建议。     

荚果蕨的人工繁殖

荚果蕨(Matteucaia Struthiopteris.T)又名广东菜、黄爪香,是林区民间食用的蕨类山野菜之一,味清香、脆嫩,别具风味.因其形状和颜色美丽,常被日本人作为主菜的点辍和装饰料,使主菜平增光彩;又因其形态秀丽,青翠可爱,生命力强,常作绿化观赏植物,赋予“草苏铁”之称.     

大亮子河国家森林公园野生观赏植物资源调查

对大亮子河国家森林公园野生观赏植物的种类及应用价值进行调查研究。结果表明,公园内共有野生观赏植物共计67科,157属,218种(含2变种)。其中蕨类8科9属11种,裸子植物2科7属9种,被子植物57科141属198种。按观赏植物的园林用途将其分为园景树、庭荫树、行道树、绿篱植物、垂直绿化植物、盆栽和盆景植物、花坛和化境植物、切花植物、水体绿化植物、草坪及地被植物共10大类。同时对合理开发利用野生观赏植物资源的提出建议。     

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.     

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.