合江方竹和刺方竹13种不同种源方竹笋营养成分研究

利用不同方法测定了浙江省内合江方竹和刺方竹13种不同种源方竹笋的水分、粗脂肪、灰分、粗纤维、维生素C、蛋白质、铁、锰、铜、锌、还原糖、氨基酸等营养成分,结果表明,方竹笋含有丰富的蛋白质,13种不同种源方竹笋干的蛋白质平均含量为28.11%,鲜笋的蛋白质平均含量为2.48%;氨基酸种类齐全丰富,含有17种氨基酸,干笋氨基酸总量的平均值为10.7445g/100g,鲜笋氨基酸总量的平均值为0.9501g/100g,鲜笋中鲜味氨基酸(天门冬氨酸和谷氨酸)总量的平均值为219mg/100g,明显高于普通的食用笋;13种不同种源方竹笋中,"丽水种源"合江方竹、"杭州种源"合江方竹等7个种源的干笋营养成分含量值更高,而"莲都种源2"刺方竹、"莲都种源1"刺方竹、"景宁种源"刺方竹等6个种源的鲜笋营养成分含量值更高。     

刚竹属8种笋用竹种鲜竹笋营养成分分析

采用最新的国际标准方法测定了刚竹属8种笋用竹种鲜竹笋蛋白质、粗纤维、还原糖、灰分等主要营养成分和氨基酸含量。结果表明,8种笋用竹种竹笋还原糖含量普遍为1.20～1.50 g·100 g~(-1),蛋白质含量为2.65～3.62 g·100 g~(-1)。以白哺鸡竹笋和红哺鸡竹还原糖含量较高,还原糖含量在1.40 g·100 g~(-1)以上;毛竹和花哺鸡竹为2种高蛋白竹种,蛋白质含量分别为3.62 g·100 g~(-1)和3.61 g·100 g~(-1)。红哺鸡竹口感较优,且粗纤维、灰分含量不高,是食用佳品。8种笋用竹种竹笋中氨基酸种类齐全,除了色氨酸外,16种常见的氨基酸均被检出,氨基酸总量(T)均高于大白菜、蒜苗、韭菜、芫荽、空心菜等常见蔬菜。白哺鸡竹竹笋和黄秆乌哺鸡竹竹笋的人体必需氨基酸(E)含量较高,E/T分别为37.704、36.029,超过了一般的蔬菜。甜竹、毛竹和高节竹竹笋中儿童必需氨基酸含量(CE)均在0.191 g·100 g~(-1)以上。     

采收期对3种笋用竹竹笋营养及氨基酸含量的影响

为探明不同采笋期对竹笋品质及营养成分的影响,对红哺鸡竹(Phylostachys iridescens)、白哺鸡竹(Ph.dulcis)和黄秆乌哺鸡竹(Ph.vivax'aureocaulis')3种笋用竹不同采笋期竹笋蛋白质、粗纤维、还原糖、灰分含量和氨基酸质量分数进行了测定.结果表明,3种笋用竹竹笋蛋白质干基含量均在310 g/kg以上,红哺鸡竹还原糖干基含量为107.0—188.1 g/kg,而白哺鸡竹和黄秆乌哺鸡竹还原糖含量分别为66.1—117.2,72.1—121.0 g/kg.3种笋用竹竹笋中粗纤维含量为43.0—84.2 g/kg,脂肪为26.0—36.0 g/kg.采收期异同不仅影响竹笋的粗纤维和灰分含量,也会影响到竹笋中蛋白质、脂肪、还原糖,但不同竹种的含量变化有所不同.红哺鸡竹竹笋中脂肪、蛋白质含量随采集时间的推后含量递减,但还原糖含量递增,而白哺鸡竹和黄秆乌哺鸡竹竹笋中脂肪、蛋白质含量随采集时间的变化不明显.3种笋用竹竹笋氨基酸总量(T)变化在13.06—35.4 g/kg,E/T值均在33.0以上.红哺鸡竹竹笋的T值随采收期的延后含量增加,而白哺鸡竹和黄秆乌哺鸡竹竹笋的T值则呈现出随采收期的延后含量递减,儿童必需氨基酸总量(CE)呈现类似的变化.竹笋营养成分和氨基酸的时令变化对于指导竹笋采集和竹林经营具有一定指导意义.     

高节竹与毛竹鞭笋品质和适口性比较

高节竹是优良的笋材兼用竹种, 竹鞭延伸生长能力强, 具有较高的鞭笋生产潜力。为评价高节竹鞭笋品质和适口性, 以毛竹鞭笋为对照, 比较两者外观形态和营养物质、呈味物质含量的差异。结果表明:与毛竹鞭笋相比, 高节竹鞭笋略长, 个体质量、基径和蛋白质、纤维素、木质素、单宁、草酸、总酸含量明显较低, 而可食率、糖酸比和脂肪、可溶性糖含量明显较高。高节竹、毛竹鞭笋除鲜味氨基酸含量差异不明显外, 高节竹鞭笋的氨基酸总量及其它氨基酸组分的含量显著低于毛竹鞭笋, 但鲜味氨基酸、甜味氨基酸和芳香类氨基酸组分比例显著高于毛竹鞭笋, 苦味氨基酸组分比例明显低于毛竹鞭笋。研究表明, 高节竹鞭笋较为粗大、可食率高、粗糙度低、适口性好, 质量总体优于毛竹鞭笋。     

不同地区银杏花粉氨基酸含量的差异性

以氨基酸总量为测量指标,对我国不同地区银杏花粉的氨基酸总量进行分析测定,结果表明:不同地区百年左右的银杏古树花粉的氨基酸总量差异较大,平均为23.431 69 g(以100 g花粉为单位,其余同);银杏花粉中含有人体所必需的8种氨基酸,每100 g花粉中8种必需氨基酸的平均含量为5.925 484 g,并且必需氨基酸在氨基酸总量中所占的比例较高;在这20个单株中,银杏花粉的氨基酸总量含量最高的是泰兴02为26.444 22 g,此外,重庆01、郯城01、通江02、嵩县02、西峡02、长兴04、奉化01、桂林09、天目01的氨基酸总量超过24 g.     

少穗竹和四季竹竹笋的营养成分分析

对福建省华安竹种园2种少穗竹属笋用竹少穗竹和四季竹竹笋的基本营养成分进行测定分析。结果表明：四季竹竹笋的含水量、灰分、脂肪含量高于少穗竹,但蛋白质含量低于少穗竹;而少穗竹竹笋氨基酸、必需及半必需氨基酸、呈味氨基酸总含量高于四季竹。     

毛竹笋氨基酸含量的比较

在毛竹冬笋和春笋两个不同生长时期,对笋体各部位氨基酸含量进行测定分析。发现不同时期笋体中组成蛋白质的氨基酸种类齐全含量高;必需氨基酸占氨基酸总量的２７．５％￣３０．５％,竹笋作为蔬菜,比较发现其必需氨基酸含量与马铃薯相当,比茄子,胡萝卜等高。     

厚竹出退笋规律及退笋过程中营养成分的变化

【目的】调查厚竹出退笋规律,探讨厚竹退笋过程中营养品质的变化特点,为合理利用退笋、提高厚竹林的综合效益提供理论依据。【方法】观察厚竹竹笋的高生长过程,统计出笋量和退笋量,测量竹笋高度,总结厚竹出退笋规律;并采用常规化学成分分析方法测定退笋不同阶段营养成分的含量,原子吸收分光光度法测定矿质元素含量,全自动氨基酸分析仪测定氨基酸含量,分析退笋过程中营养成分的变化规律。【结果】1) 2015年、2017年和2018年厚竹出笋量分别为1 171、818和575株,出笋规律呈正态分布曲线,且从出笋初期至末期退笋率升高。退笋高度主要集中在50 cm以内,其中30 cm高度以下的退笋占比分别高达69. 81%、83. 60%、86. 09%,且在相同时间内,退笋高生长量低于正常笋。2)与正常笋相比,厚竹退笋的粗蛋白、可溶性糖和淀粉的含量均下降,而灰分、酸性洗涤纤维则高于正常笋,脂肪含量与健壮笋无显著差异(P0. 05);厚竹不同矿质元素含量由高到低依次为:PMgCa Zn Mn Fe Cu,其中P含量表现为正常笋高于退笋,其余均是退笋显著高于正常笋(P0. 05),且随退败程度加深呈增加趋势;厚竹退笋与正常笋都含有17种氨基酸,退笋氨基酸总含量显著低于正常笋,且随退败程度加深呈下降趋势,退笋中期和后期氨基酸总量无显著差异。但退笋中主要鲜味类氨基酸含量比例增加。【结论】厚竹每年大量出笋,大小年差异没有毛竹明显,更适于培育优质竹林,具有较高的经济价值。厚竹退笋率整体较高,退笋高度集中分布在50 cm以内。厚竹退笋主要集中在高生长初期。厚竹退笋仍富含蛋白质、氨基酸、矿质元素等物质,具较高的食用价值,及时开发利用退笋可提高竹林生产效益。     

锡金龙竹竹笋的营养成分分析与评价

对锡金龙竹鲜笋的矿物质、微量元素、蛋白质、粗纤维、总糖和氨基酸的含量进行了分析测定,并与版纳甜龙竹、勃氏甜龙竹、马来甜龙竹和麻竹竹笋以及6种常用蔬菜的相应含量进行了比较.结果表明:锡金龙竹鲜笋的蛋白质、脂肪、粗纤维、总糖及二氧化硫含量分别为227.7 g/kg,24.6 g/kg,82.7 g/kg,209.3 g/kg和2.65 g/kg,其蛋白质、粗脂肪含量与4种甜龙竹竹笋相当,蛋白质明显高于常用蔬菜,而粗脂肪含量略低于常用蔬菜.其每kg竹笋干物质中矿质元素和微量元素的含量为:P 9.33 g,Ca 42.33 g,K 367.67 g,Mg14.33 g,Fe 5.0 g,Zn 4.6 g,Cu 1.0 g,Mn 3.8 g, 略低或接近于4种甜龙竹竹笋,但明显高于所有参试的常用蔬菜.其锌铜比值为4.60,锌铁比值为0.92,说明锡金龙竹鲜笋所含的铜、铁、锌的比值是比较合理的.其蛋白质中含有17种氨基酸,包括9种人体必需氨基酸,总氨基酸(TAA)、人体必需氨基酸(EAA)和人体非必需氨基酸(NEAA)的含量分别为182.17 g/kg,54.39 g/kg,78.67 g/kg,都高于所有参试的常用蔬菜,其氨基酸总量略高于4种甜龙竹的竹笋.其所含的人体必需氨基酸占总氨基酸(EAA/TAA)的29.86 %,人体必需氨基酸与非必需氨基酸的比值(EAA/NEAA)为69.14,符合FAO推荐的理想蛋白模式,其第一限制性氨基酸为含硫氨基酸,即蛋氨酸和胱氨酸,第二限制性氨基酸为异亮氨酸.认为,锡金龙竹鲜笋中富含矿质元素、微量元素和氨基酸,其粗蛋白质与粗纤维含量明显高于粗脂肪含量,属高蛋白、高纤维、低脂型且营养丰富、具有很高开发潜力的野生食用竹笋.     

5种牡竹属笋用竹竹笋营养成分之比较

对福建省华安县竹种园5种牡竹属笋用竹云南甜龙竹、版纳甜龙竹、勃氏甜龙竹、马来甜龙竹和梁山慈竹竹笋营养进行成分比较。结果表明:5种笋用竹鲜竹笋含水量均接近或超过90%,口感较好;灰分含量勃氏甜龙竹竹笋的最高,达0.893%,版纳甜龙竹最低(0.340%);蛋白质含量最高的是马来甜龙竹(1.717%),最低的是版纳甜龙竹(1.260%);勃氏甜龙竹(0.281%)和云南甜龙竹(0.292%)脂肪含量较低,马来甜龙竹(1.134%)和梁山慈竹(1.083%)脂肪含量较高;勃氏甜龙竹(0.655%)和云南甜龙竹(0.666%)粗纤维含量较低,而梁山慈竹、版纳甜龙竹和马来甜龙竹含量相近,达较高水平,分别达0.953%、0.894%和0.879%。5种竹笋均含有17种氨基酸,氨基酸总含量最高的是勃氏甜龙竹(227.64 mg·g~(-1)),最低的是马来甜龙竹(120.43 mg·g~(-1));必需半必需氨基酸总含量最高的是勃氏甜龙竹(84.26%),最低的是马来甜龙竹(50.67%);呈味氨基酸总量最高的是勃氏甜龙竹,达212.79 mg·g~(-1),其次依次为梁山慈竹(164.71 mg·g~(-1))、版纳甜龙竹(156.35 mg·g~(-1))、云南甜龙竹(141.44 mg·g~(-1))和马来甜龙竹(115.83 mg·g~(-1))。     

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.