石榴籽油脂肪酸组成分析

用气相色谱分析石榴籽油的脂肪酸组成,共检出6种脂肪酸。其中以石榴酸(十八碳共轭三烯酸)为主,占83%,另有棕榈酸、油酸、亚油酸及少量硬脂酸和亚麻酸。与桐油脂肪酸组成进行比较,推断石榴籽油可作为油漆、涂料等工业的油源加以开发利用。     

沙棘油鉴别方法初探

通过分析沙棘油与常见植物油在理化指标及生化成分上的区别，继而讨论了利于脂肪酸组成进行鉴定的方法，分别探讨了沙棘果汁油与沙棘种子油的鉴别，提出了对混有月桂酸类油脂，棕榈酸类油脂、油酸及亚油酸类油脂的鉴定方法。     

沙棘油掺伪的鉴别

通过对比分析沙棘籽油、沙棘果肉油、一般植物油、动物脂的脂肪酸组成,V—E、甾醇含量组成及其变化,可对沙棘油掺伪进行鉴别。     

栝楼籽油的理化性质及其脂肪酸组成分析

采用索式提取器萃取栝楼籽油,经甲酯化处理后,用气质联用仪（GC-MS）对栝楼籽仁油的脂肪酸组成进行分析和鉴定,面积归一法计算各种成分的质量分数,并对其理化性质进行分析研究。结果表明：从栝楼籽仁油中捡出19种脂肪酸：10种饱和脂肪酸,以棕榈酸、硬脂酸为主,占脂肪酸总量8．019％;9种不饱扣脂肪酸,以油酸、亚油酸和栝楼酸为主,占总量的91．603％。理化测定结果表明：栝楼籽的出仁率为55．8％,种仁含油率为51．4％,折光指数为1．4831,皂化价为190．2mg KOH／g,碘价为120．9gI2／100g,酸价为1．62mgKOH／g,过氧化值为0．85meq／kg,可见栝楼籽油是一种值得开发利用的营养保健油源。     

四种天然食用植物油脂的脂肪酸成分分析

运用气相色谱技术对油茶籽油、牡丹籽油、橄榄油和核桃油的脂肪酸组成进行了分析。结果表明:4种油脂脂肪酸组成相似,主要由油酸、亚油酸、亚麻酸和棕榈酸组成,但不同脂肪酸的含量相差较大。油茶籽油脂肪酸中油酸含量最高为82.43%,核桃油脂肪酸中亚油酸的含量最高为62.91%,牡丹籽油脂肪酸中亚麻酸的含量最高为41.78%,油茶籽油、牡丹籽油、橄榄油和核桃油的不饱和脂肪酸含量分别达到90.04%、93.08%、85.43%和92.11%,4种油脂均具有很高的营养和保健价值。     

基于气相色谱法的福建油茶籽油真伪鉴别

采用气相色谱法对大豆油、玉米油、菜籽油、葵花籽油、棕榈油以及福建14个地方的油茶籽油的脂肪酸组成和含量进行测定,并研究在油茶籽油中掺入不同比例大豆油、玉米油、菜籽油、葵花籽油、棕榈油后掺伪油样中的脂肪酸组成和含量的变化。结果表明,棕榈酸、油酸、亚油酸、亚麻酸可作为鉴别油茶籽油的特征脂肪酸,通过分析掺伪油样中特征脂肪酸含量的变化趋势,可以定性定量地鉴别油茶籽油的掺伪情况。该研究结果可为福建地区油茶籽油真伪的鉴定提供参考。     

云南高原山地油茶籽油脂肪酸组成及品质分析

为了解云南高原山地油茶籽油品质及其脂肪酸组成和含量,以云南高原山地主产区初选的37株油茶优树为研究对象,检测分析37株油茶优树的油茶籽油.结果表明:云南高原山地油茶籽油平均含油率为46.87％,油脂主要由油酸、亚油酸、棕榈酸、硬脂酸、亚麻酸等脂肪酸组成,其中不饱和脂肪酸含量占90％左右,油酸含量72.52％ ～84.7...     

沙棘果汁油沙棘果渣油和沙棘种子油的区别

综合分析沙棘果汁油、沙棘果渣油和沙棘种子油在理化指标和生化成分上的差异发现,沙棘果汁油与沙棘果渣油的生化成分基本相同。在理化指标（除碘价外）方面三者差异不大,沙棘种子油的碘价明显偏高。在生化成分方面,抄棘果渣油和沙棘果汁油的类胡萝卜素含量远高于沙棘种子油,三者V—E的含量近似,在脂肪酸组成方面,沙棘果汁油和沙棘果渣油主要是榈酸、棕榈油酸和油酸,沙棘种子油主要是棕榈酸、油酸、亚油酸和亚麻酸。不皂化物方面,果汁油中含有豆甾醇类和谷甾醇类化合物,种子油中不含谷甾醇,仅含一种豆甾醇。     

不同提取方式下塔拉籽油提取率及其相关性质的研究

采用不同提取方式对塔拉籽油提取率、理化指标、脂肪酸构成进行测定的结果表明:在索氏、超声、超临界3种提取方式中,超临界在塔拉籽油的提取率和脱酸方面表现最好,相关理化指标的表现也较好;塔拉籽油脂含有棕榈酸、棕榈油酸、硬脂酸、油酸、亚油酸、花生酸、亚麻酸、二十二碳酸等8种脂肪酸,不同提取方式对脂肪酸构成及含量无明显影响,超临界为塔拉籽油最优提取方式。     

主产区浙江红花油茶籽仁含油率及脂肪酸组成变异分析

【目的】探讨浙江红花油茶油用性状的变异规律,为浙江红花油茶品质育种和引种栽培提供基础数据与科学依据。【方法】选取了江西、浙江、福建省浙江红花油茶主产区内的6个优势林分,采用索氏提取法提取干籽仁油,利用气相色谱法对不同产地浙江红花油茶油脂的脂肪酸组分和含量进行测定和分析,并采用相关性分析法、多重比较法及巢氏方差分析法对浙江红花油茶各项油用性状指标进行分析。【结果】6个产地的浙江红花油茶其籽仁含油率的总均值为58.46%,其中,籽仁含油率大于60%的样株数占供试样株总数的52%。各个产地的平均籽仁含油率从大到小依次为福建武夷山、福建霞浦、浙江开化、江西德兴、江西乐平和江西婺源。统计所有供试样株的数据可知,浙江红花油茶的油脂以油酸为主,且其变异系数最小(2.64),而油酸大于81%的样株数占供试样株总数的50%以上。在其脂肪酸组成中,油酸与亚油酸组分含量间呈极显著负相关。籽仁含油率在不同产地间及相同产地内的差异均不显著,而各脂肪酸组分在不同产地间均呈极显著差异。对油脂性状指标与不同产地地理生态因子间的相关性分析结果表明,籽仁含油率受不同地理生态因子的影响差异未达到显著水平,而年均温与年均湿度对浙江红花油茶籽仁油中脂肪酸组成的影响均较大。【结论】在种子发育进程中,相对较高的温度和相对较低的湿度可能有利于种子中油酸的积累。此外,除了总脂肪酸含量与产地海拔呈一定的负相关,不同产地的海拔差异与浙江红花油茶各项油脂性状指标间总体上均无显著相关性,表明从高海拔区域向低海拔区域引种浙江红花油茶对其油脂品质无明显影响。     

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.