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。     

无患子种质皂苷性状分析评价及优良种质选择

为筛选皂苷性状优良的无患子(Sapindus mukurossi)优良种质,对调查收集的10个无患子种源67个优良单株的皂苷性状展开分析评价,研究结果表明:不同种源的无患子皂苷产出率为14.20%～24.32%,总体平均值为20.12%。皂苷产出率比较高的种源有福建顺昌、云南石林、浙江萧山、福建延平,分别比种源总体平均值增加20.87%、13.72%、11.28%、10.83%,但不同种源间皂苷产出率差异不显著。高皂苷种质材料选择单株选择优于种源选择。67株优良单株皂苷产出率为5.6%～33.2%,总体平均值为20.11%,优良单株之间皂苷产出率差异显著。聚类分析表明,第一类为皂苷产出率优势明显的优良单株(sc04、xs05),皂苷产出率平均值为32.95%,比总体平均值提高63.8%;第二类(27个单株),皂苷产出率平均值为25.83%,比总体平均值提高28.4%;第3类(35个单株),皂苷产出率平均值为16.0%,低于总体平均值;而第4类(2个单株)、第5类(1个单株)皂苷产出率远低于总体平均水平,分别只有9.45%、5.6%。皂苷产出率(Y)与经度(X_1)呈密切正相关,与果肉千粒重(X_8)、果实鲜果重(X_5)呈密切负相关,与果核千粒重(X_7)、果肉比(X_6)、树高(X_3)、胸径(X_4)、纬度(X_2)等5个因子相关性不明显。     

不同种源江南油杉球果种子品质差异

以来自广西、福建15个种源江南油杉种子为材料,分析比较不同种源江南油杉种实在表型性状、萌发特性上的差异,为优良种源的早期选择及进一步的选种育种和种子生产提供参考。结果表明:江南油杉饱满种子千粒重106.86~193.35 g,近50%的种源其种子饱满率低于50%,田间出苗率种源间平均值为41.78%。江南油杉种实生物学性状种源间差异显著,产地效应明显。种子饱满率、田间出苗率、单果重和球果体积变异幅度较大,球果直径和种子形态指标的变异幅度较小。主成分分析结果表明,田间出苗率和果径比是江南油杉种子品质构成的最重要因子,千粒重和饱满率是次重要因子。江南油杉种子生物学性状不同产地间差异显著,这对江南油杉种源的选择与改良具有积极意义。综合4项重要指标对本研究中15个种源江南油杉种子评价得出,广西以恭城和大桂山种源种子较优,福建以福清、闽侯、闽清、永泰、邵武种源种子较优。     

闽楠种源试验初步研究

通过对福建省永安国有林场2005年栽培的21个种源闽楠（Phoebe boumei）试验林进行连续8年的调查分析,结果表明：闽楠种源间树高、地径生长性状存在极显著差异,这些差异主要是由种源本身的遗传特性决定.以9年生闽楠的树高、地径为选择依据,初选出明溪沙溪、福建永安、福建浦城、江西上饶等4个优良种源,其树高平均值为291.84cm,比总体平均值高36.7％,遗传增益为30.00％;地径平均值为4.29cm,比总体平均值高37.5％,遗传增益为31.93％.这些优良种源可用于闽楠珍贵用材林基地造林.     

毛红椿种子性状的种源差异及综合评价

为揭示毛红椿种子性状的地理变异规律,测定了毛红椿6个种源的种子表型、种子品质及其内含物含量等14个指标,研究种子性状的种源差异,并通过主成分法及聚类法对种子性状进行综合评价。除种子长和淀粉含量外,不同种源种子的其他性状差异均达极显著水平(P<0.01),种子性状变异系数的范围为6.09%～26.99%,其中种子表型特征变异系数平均值最小(7.93%)。江西宜丰种源的种子千粒重(7.81 g)显著高于其他种源,发芽率(81.93%)最高。种子千粒重与发芽率、可溶性糖含量及非结构性碳水化合物含量之间呈极显著正相关(P<0.01),说明毛红椿种子的重量与其所含的内含物的含量有关。种子性状的主成分分析结果表明,特征根大于1的主成分有3个,其贡献率分别为43.82%、 32.48%、15.01%,累计贡献率达91.31%。聚类分析将6个种源分为3个类群,第Ⅰ类群是江西宜丰种源,为高千粒重、高可溶性糖和高非结构性碳水化合物类群;第Ⅱ类群是江西龙南种源;第Ⅲ类为江西茅坪、福建南平、浙江富阳和湖北恩施种源。整体来说,毛红椿种子性状在种源间具有较强的遗传改良潜力,种子表型特征比种子品质和内含...     

杉木速生优质种源多性状选择研究

对杉木种源两次全分布区试验的13、16、18、28年生试验林的生长、材性测定资料进行了研究,结果表明:杉木种源间的树高、胸径、材积、木材比重、形数等性状都存在着丰富的遗传变异,其种源的遗传力在中等以上;以速生优质为目标作综合指数选择,从57个参试种源中,评选出福建崇安、建瓯、浦城、贵州锦屏、广西融水、福建武平、南平7个优良种源,其中广西融水、贵州锦屏、福建南平为稳定性好种源,在13年生时其材积遗传增益为417%～823%,在28年生时,其树高、胸径、材积现实增益分别为77%～156%、99%～309%、308%～911%;生长性状与木材比重无显著的表型相关,但两者遗传相关呈负向,随林龄增加达到高度负相关,生长性状的改良有降低木材比重的趋势;广西融水、贵州锦屏等优良种源早期就表现出速生性,而福建崇安、浦城、建瓯等武夷山闽西北山地种源,前期速生性并不十分显著,随林龄增大,其生长速率加快,直径生长尤为突出,具有巨大的生产潜力,更适合在浙江省推广应用。杉木种源研究应延续到半个轮伐期以上。     

樟树不同地理种源生长性状差异研究

通过对引种在厦门地区9个樟树种源的生长性状进行调查,结果表明,不同地理种源的樟树生长差异较大,综合地径和树高生长的情况,总体生长表现比较好的种源是广东揭阳(GD1)、广东和平(GD2)、广东梅州(GD3)、福建南靖(FJ1),地径平均值达3.1~3.4cm,树高平均值为221.7~236.6cm,这些种源适于厦门地区栽培和推广。方差分析结果表明,樟树不同地理种源各生长性状差异显著。选择种源时,应尽量选择同一种源区内的地理气候因子相近的地区作为种源区进行引种,以保证引种后幼树生长状况良好。     

15年生大青杨种源生长性状的遗传变异及优良种源选择

以带岭试验点15年生大青杨种源林的生长性状为材料,通过综合分析,揭示大青杨生长性状的地理变异规律,评选优良种源并进行优良种源区的划分。结果显示:8个种源11个个体15年生胸径的变异幅度为8.60~30.5 cm,平均值是15.97 cm,超过平均值的有5个种源、6个无性系,占参试种源的62.5%,其中加格达奇种源的C7为最优种源中的优良个体,15年生胸径20.10 cm,大于群体平均值26%,年平均生长量达1.34 cm;从大青杨种源间生长性状的方差分析得出:胸径、材积在种源间均达到极显著水平;多重比较结果看出,不同种源生长量存在着很大差异;综合胸径、材积生长指标评选优良种源,加格达奇、延边、苇河3个种源入选,其中加格达奇为最优种源,胸径、材积、指标均排在第一位;依据种源划分原则,划定为两个种源区,即长白山种源区和小兴安岭种源区。依据种源林15年的试验结果,确定长白山种源区最佳种源是延边;小兴安岭种源区最佳种源为加格达奇。     

福建柏地理种源湖南试点幼林期结果初报

研究表明,福建柏17个地理种源和48个家系幼林期树高、胸径、材积生长在山区、半山区、丘陵区均有极显著差异,其树高、胸径、材积遗传力值分别达0.556 1～0.9034、0.630 3～0.914 0、0.670 1～0.914 3,反映该差异主要受遗传因素影响.种源×地点交互作用显著,其3个主要性状生长量山区＞半山区＞丘陵区.根据材积遗传增益大于种源平均值15%以上的选择标准,初步选择出适宜不同生态环境造林地的10个优良种源和14个家系,其材积遗传增益分别为16.09%～88.70%、15.19%～184.80%.     

闽南山地红锥种源对比试验

为选择红锥优良种源,对在闽南山地开展的7个红锥种源试验林进行对比分析、评价与选择,结果表明:参试种源的适应性较强,各种源造林成活率和保存率均较高,且种源间差异小;从生长性状看,苗期和幼树期以葛山漳平、福建华安、广西凭祥和福建安溪的种源较好;7 a林龄幼林期,不同种源的树高、胸径和材积均存在极显著差异,且遗传方差均大于环境方差,遗传力分别达88.79%、86.64%和88.66%。生长性状最优的种源为福建华安、广西凭祥和福建安溪,它们的树高、胸径和材积比群体均值分别提高9.33%~14.12%、9.12%~18.52%和20.51%~50.57%。综合分析结果,初步选择出福建华安种源、广西凭祥种源和福建安溪种源为优良种源,树高、胸径和单株材积遗传增益分别达4.66%~12.54%、7.90%~16.05%和18.19%~44.84%。     

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.