欧美杨无性系区域试验的效应分析与稳定性测定

欧美杨无性系区域试验的效应分析与稳定性测定王克胜，卞学瑜，李淑梅，佟永昌，韩一凡关键词欧美杨无性系，区域试验，稳定性，基因型和环境互作基因型和环境互作日益受到遗传育种工作者的重视，选育出的优良品系，要经过区域试验来确定其适应性和适生范围，才能推广。在...     

杨树农田防护林带单木枝面积的变化

枝面积指数同叶面积指数一样,是重要的林分结构特征,但叶面积指数更受重视,而枝面积指数常被忽略(Weiskittel et al.,2006).枝面积对总呼吸、光能辐射及降雨截留等多种生理生态过程具有重要意义(Bosc et al.,2003;Keim,2004);枝面积及其垂直分布对森林生物多样性具有重要意义( Ingram et al.,1993).由于受重视程度不够,目前对枝面积 研究仅限于较少的几个树种(Baldwin et al.,1997;Bosc et al.,2003;Halldin,1985;Ingram et al.,1993;Jennings et al.,1990;Keim,2004;Weiskittel et al.,2006),且研究的深度和广度比较有限.林带的结构影响着防护林的防护效能,而枝面积是重要的林分结构特征,因此,研究农田防护林带的枝面积及其分布对研究林带的防护效能具有重要意义.     

基于mtDNA-COI基因序列的针叶小爪螨种群遗传结构影响因素分析

寄主植物、地理距离、农药胁迫、生境片段化等是影响种群遗传结构和进化的重要因素(Harrison etal.,1996;Hutchinson et al.,1999;Knutsen et al.,2000;罗育发等,2006;褚栋等,2008)。许多有关昆虫与植物间关系的研究发现植食性昆虫具有通过缩小或扩大其寄主范围或转移到新寄主上的进化潜力(Via,1990),这种现象可能使种群间产生完全的     

辽东山区次生林3种大小林窗夏季近地面气温及土壤温度比较

20世纪70年代以来,林窗已成为森林小尺度干扰研究的热点(Whitmore,1989;王进欣等,2002).林窗是森林中具有特殊性质的微结构(Clinton et al.,1993;Gray et al.,1997;梁晓东等,2001;Gagnona et al.,2004),它影响着森林群落的发展方向、物种组成以及种群动态(Spies et al.,1990;安树青等,1997;Zhu et al.,2006),如有些物种只能通过林窗才能进行更新(谢宗强,1999;贺金生等,1999).     

缙云山常绿阔叶林木本植物种子大小变异及成因探讨

在植物的性状中,种子大小处于中心地位(张世挺等,2003),种子大小对物种生物学和生态学特征产生一系列影响(Thompson et al.,1998;Moles et al.,2003;Howe et al.,2001;Xiao et al.,2004;Pearson et al.,2003;Tungate et al.,2002;Christie et al.,2003;Rodríguez-Gironés et al.,2003;Tumbull et al.,1999;Tsuyoshiet al.,2001).种间种子大小变异被认为是种子大小变异的中心问题(Haig,1989;Silvertown,1989),因此,从植物区系组成的角度比较种间的种子大小是种子生态学研究中的一个重要内容(Fenner,2001),它对深入认识一个地区植被的物种多样性维持机制,保护和合理利用乡土植物资源都有重要意义.     

氮素营养对长白落叶松移植苗生长及养分状况的影响

尽管少数研究认为造林效果与苗木体内氮含量无关甚至负相关(Gleason et al.,1990;Boinvin et al.,2004),更多的研究表明初始氮含量与造林效果呈正相关,如蓝桉(Eucalyptus globulus)高、低氮处     

12个欧美杨无性系生长初期基因型与环境的互作效应

【目的】研究12个欧美杨杂交无性系生长初期在不同环境下生长性状的观测值变异,从基因型与环境互作效应的角度入手,筛选可以推广的稳产、丰产的优良基因型;总结试验中适地适品种的规律;评价试验地点的区分力和代表性。为后续欧美杨的育种工作提供相关技术支撑。【方法】试验材料为3年生的12个不同基因型的欧美杨杂交无性系,设计了辽宁黑山、河北滦南、湖北石首和山东诸城、郓城、宁阳6个试验地点,测定树高、胸径,计算变异系数和均值进行初步比较,利用ASReml-R软件建立混合效应模型,利用预测性状值作GGE双标图,分析并总结其中规律用以评价试验地点和筛选优良基因型。【结果】整体上胸径的变异大于树高,黑山和石首的变异较大。均值统计的结果表明,不同基因型的生长性状在同一环境下的表现不同,同一基因型的生长性状在不同环境下的表现也不同;经混合线性模型检验,基因型、环境及基因型与环境的互作对于生长初期的欧美杨树高、胸径存在极显著(P0.01)的效应,由区组带来的效应也极显著。提取性状预测值作GGE双标图,拟合度均在80%以上,结果近乎与实际情况一致。GGE双标图的结果表明,对于树高的表现和胸径的表现,环境间的关系相似但不相同;树高、胸径的表现均存在交叉性互作现象;入选基因型有5号、7号、3号、4号和9号,其中4号、5号和7号为全同胞家系。父本的遗传物质和种源地对杂交无性系的表现有明显可见的影响,荷兰北方型的欧洲黑杨N146是优良的父本材料。【结论】1)生长初期欧美杨杂交无性系树高、胸径在东北地区和华中地区变异较大;欧美杨杂交无性系在生长初期的生长性状受基因型、环境及其交互作用的显著影响。2)由GGE双标图中的信息,综合筛选出丰产性较高稳产性最高的基因型7号、丰产基因型5号、高于平均产量且丰产稳产都较好的基因型4号。3)在黑山地区和诸城地区适合栽植基因型3号和4号;在宁阳地区和石首地区适合栽植5号基因型;滦南地区和郓城地区适合栽植7号基因型。     

连栽杉木林不同生育阶段林下植被生物量

林下植被是森林生态系统的一个重要组成部分,亦是森林生态系统中有机物质的生产者,在森林生态系统的物质循环研究中具有重要作用(Chpin,1983;Chastain et al.,2006),如维持森林生物多样性(褚建民等,2007)、提高人工林的水土保持功能(袁正科等,2002)和保护环境(刘苑秋等,2004;Fabia et al.,2002;Kume et al.,2003;Taylor et al.,2006).对森林林下植被结构和生态功能的研究已有不少报道(Taylor et al.,2006;吴鹏飞等,2008;李春义等,2007;段劼等,2010).     

水曲柳种群性比及空间分布

雌雄异株植物的雌雄植株在营养和繁殖结构的大小、颜色及寿命,资源获得与分配,与群落其他物种相互作用等方面均存在差异(Delph et al.,1996;2002;Pickering,2000;Gehring et al.,1994).种群性比是雌雄异株植物的一个重要结构指标,尽管雌树多于雄树(Opler et al.,1978;Alliende et al.,1989),以及性比不显著偏离1:1(Morellato,2004)的种群结构已经被发现,但大量研究显示雄树通常多于雌树(Pickering,2000;Gauquelin et al.,2002;Pickering et al.,2002).     

桉树无性系生长性状的基因型与环境互作初步研究

针对桉树人工林造林树种单一以及华南地区台风和病虫害对桉树人工林产量影响严重等问题,开发测试并推出新无性系对解决这些问题尤为重要。本研究对15个桉树新无性系在5种立地条件下的生长表现进行了分析,并对生长性状的基因型与环境互作效应做了定性分析。测试无性系的生长表现显示,无性系1409在所有立地中的表现均优良且稳定,无性系1406和1407在多个试验点的表现优良。这3个无性系在不同的立地条件下表现出较为稳定的生长优势,其广泛的适应性表明其具有潜在的推广价值。来自5种立地条件的无性系生长性状的方差分析显示,测试无性系在无性系、立地及无性系与立地互作水平均存在显著的差异(P0.01),主要原因在于这5种立地条件的温湿度、降雨量和土壤类型均存在较大差异。该结果也说明了进行无性系多立地条件测试的重要性,尤其是针对华南地区不同的立地类型。测试无性系胸径和树高的重复力都很高(0.972和0.964),表明其虽然在不同的环境条件下存在生长差异,但其生长表现还是具有很高的稳定性。本研究结果在一定程度上可为桉树无性系的选优、中试甚至推广决策的制定提供一些借鉴。     

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.