浅谈杏扁良种基地建设的必要性

杏扁是我国特有的树种,具备抗寒、耐旱、耐瘠薄、易管理的特点,经济效益显著,现已逐渐成为河北省北部山区防护林、生态林建设的主要经济林树种之一。然而,目前河北省杏扁生产上存在品种结构不合理、栽培管理技术落后、早春冻害严重等问题,应建立杏扁良种基地,选育良种,研究良法,以推动杏扁业发展。     

甘河林业局国家重点兴安落叶松良种基地建设的必要性及需求分析

文章通过对基地的基本情况、发展目标及建设的必要性和需求情况进行了翔实的论述,为大兴安岭林区良种基地的发展提供参考。     

红花尔基沙地樟子松造林技术

红花尔基沙地樟子松造林技术本栏编辑程月华白景阳红花尔基林业局位于呼伦贝尔草原沙地与大兴安岭山地接壤地带，境内主要为松林沙土、生草沙土、黑钙土、灰色森林上，年均降水量３４４～３７５毫米，年均气温－１．５℃，适宜樟子松林木生长。为了扩大樟子松林面积，增加...     

黑龙江省桦川县落叶松林木良种基地建设

依据桦川县落叶松林木良种发展现状,结合地区性林木种苗的供需状况,较详细地论证了黑龙江省桦川县林木良种基地建设的目的、意义、背景及基地建设的必要性,分析了基地建设条件,确立了建设目标。     

黑龙江省鸡西市林木良种基地建设刍议

依据鸡西市林木良种现状,结合未来地区性林木种苗的需求量,从诸多方面较详细地论证了黑龙江省鸡西市林木良种基地建设的可行性及加快落叶松、红松良种基地建设的必要性和可行性。     

红花尔基沙地樟子松天然林枯立木特征分析

[目的]了解沙地樟子松天然纯林中枯立木的数量及空间结构特征,探究枯立木形成的原因,为樟子松林的保护和经营提供依据。[方法]在沙地樟子松天然纯林中设置2块1 hm~2的大样地,用全站仪对样地中所有胸径大于5 cm的立木进行定位并进行全面调查;对调查样地的基本特征,枯立木的数量特征及径级分布进行了分析,提出了用于表达林分中枯立木微环境的活立木比的概念,并采用林分空间结构参数一元分布和二元分布分析方法,对枯立木与其最近4株相邻木的关系进行分析。[结果]2块不同密度的樟子松天然纯林下更新幼苗和枯立木数量相差较大,密度较小(样地1)的样地更新幼苗和枯立木较少,而密度较大的样地(样地2)中枯立木达到200棵,林下更新幼苗数量达到15 280株·hm~(-2);樟子松天然纯林样地内枯立木主要以小径级木为主,胸径集中在11 cm以下;样地1枯立木径级连续分布,幅度较窄;样地2中的枯立木径级幅度较宽,但在20 22 cm缺刻,有2株大于23 cm的枯立木;2块样地中枯立木的分布格局均为随机分布,样地1中枯立木周围的4株相邻立木大多为活立木,且胸径较枯立木大;样地2中,只有一半的枯立木周围的最近4株立木为活立木,且有三分之一以上的枯立木胸径不是最小的,枯立木有连续分布的现象。2块样地中枯立木的角尺度-大小比数二元分布特征的差异不明显,而角尺度-活立木比二元分布特征和大小比数-活立木比二元分布特征差异明显,样地1中枯立木的最近4株随机分布于其周围的相邻木为活立木且胸径大于枯立木的比例明显高于样地2,而枯立木最近4株随机分布于其周围的相邻木有枯立木的比例明显小于样地2。[结论]樟子松天然纯林枯立木以小径级林木为主,枯立木的数量与林分密度相关,林木竞争是林木死亡的主要原因,密度过大也会产生病虫害,因此,对天然樟子松纯林要进行适度经营,保持合理密度。     

黑龙江省鸡西市林木良种基地建设可行性分析

依据鸡西市林木良种现状,结合未来地区性林木种苗的需求量,从诸多方面较详细地分析了黑龙江省鸡西市林木良种基地建设的可行性及加快林木良种基地落叶松、红松良种建设的必要性和重要性。     

加速林木良种基地建设提高林木良种基地效能

本文分析了影响林木良种基地质量的因素，提出提高良种基地效能的对策并对福建省良种选育和繁殖工作提出建议。     

福建省林木良种基地建设概况

本文介绍了福建省林木良种基地的概况和基地建设的基本措施，并对今后福建省的良种基地建设工作提出六个设想。     

Background pollination in Pinus sylvestris seed orchards

The proportion of background pollen grains in the seed crops of two Pinus sylvestris seed orchards in Central Finland was estimated with the aid of multilocus allozyme markers. The orchards studied were more than 30 years old and in full pollen production. For the bulked seed crops of the seed orchard with southern clones the estimated average of background pollination over four years was 26%. There were statistically significant differences between years. No significant heterogeneity in the degree of background pollination between clones was found. Among single ramets there was significant heterogeneity in the estimated contamination rates, but the variation was not related to position in the orchard. For the seed orchard with northern clones the bulked seed crop was studied only for one year and the level of background pollination was found to be 33 %. These estimates are fairly high, but lower than for many other orchards. Background pollination at this level will cause losses in expected genetic gains. Part of the seeds from northern orchards will not be adapted to the intended area of use.     

Levels of outcrossing and contamination in two Pinus sylvestris L. seed orchards in Northern Sweden

The joint levels of outcrossing and contamination in two young northern Swedish Scots pine (Pinus sylvestris L.) seed orchards were studied with the aid of allozyme markers. High levels of contamination (21–36%) were estimated and were attributed to the observed low within orchard pollen production. Outcrossing rate estimates were high (0.957–0.961), though they departed significantly from complete outcrossing (t= 1.0) in spite of the observed high contamination levels. These results confirmed reported relationships between outcrossing and contamination levels in open‐pollinated seed orchards. It was concluded that a crop management option relying on supplemental mass‐pollination would be effective in reducing both contamination and inbreeding levels.     

樟子松母树林疏伐密度研究

通过对孟家岗林场40年生樟子松母树林不同密度疏伐处理后14个主要性状的统计分析,结果表明,疏伐处理对樟子松母树多个性状造成了显著影响,而且不同性状之间存在极为复杂的相关性;利用聚类分析和主分量分析法将存在显著差异性和相关性的8个性状分成3类,分别代表了生长、树冠和结实性状;通过这3类性状在各主成分上得分值的加权和比较表明,孟家岗林场40年生樟子松母树林疏伐抚育最佳密度是150株·hm-2。     

雁北地区樟子松单木生物量模型研究

采用模型分析法研究了雁北地区樟子松的地径(D0)、胸径(D)、树高(H)、枝下高(h)、冠幅(cr)因子与各器官生物量、总生物量的相关关系。结果表明,樟子松各器官及总生物量最优模型为:总生物量ln Wat=-1.65+0.78 ln(D2H);树干生物量ln Wt=-1.15+0.91ln(D2H);树冠生物量ln Wcr=1.24+0.16D;树枝生物量ln Wb=-1.93+1.83 ln D;树叶生物量ln Wl=-1.36+1.28 ln D.     

人工樟子松幼林改建红松坚果园工艺技术

针对退耕还林后樟子松幼林改建红松坚果园的主要技术问题,进行了详细论述,指出运用好选地、调查设计、林份扶壮、嫁接与管理等工艺技术措施可保证该项技术的成功.     

Female fertility variation in mature Pinus sylvestris clonal seed orchards

Abstract

Female fertility is the basis for the output of seeds from clonal orchards and its variation is of major interest for the economics and biology of seed orchards, especially for the efficiency and diversity of seed orchard crops. Assessments of female fertility variation in 10 mature (>15 years old) seed orchards of Scots pine (Pinus sylvestris L.) were evaluated and compared. Depending on the individual orchard, fertility variation for each clone was assessed in slightly different ways, e.g. number of strobili, cones, seeds or litre of cones per ramet. Assessments in five of the orchards were made over consecutive years. The main result was that the clonal variation in mean female fertility per surviving ramet was lower than expected from the literature; the Kang–Lindgren sibling coefficient (Ψ) within individual years averaged 1.35. The variation between ramets within clones and years was of similar magnitude as that between clones. Clone by year interactions were noticeable, but were slightly lower than the variation between as well as that within clones in individual years. There was considerable variation in the variance components between years. The limited variation in female fertility indicated that it should not be a selection criterion when selecting clones for a seed orchard. Furthermore, it will not result in large differences between clones in seed set or large reductions in gene diversity in productive Scots pine seed orchards.     

榆林沙区樟子松种子园建立及经营技术

本文对榆林沙区樟子松种子园的建立和经营状况在规模确定、选址、设计、建园材料选择、种子园经营管理及遗传品质鉴定等技术方面进行了论述。     

人工樟子松林生物量预估模型的研究

根据标准地、解析木及生物量调查资料,建立了人工樟子松林叶、枝、干及全树生物量预估模型,并对模型参数进行了小样本t检验。结果表明,地上生物量与胸径密切相关,樟子松生物量随着树龄的增长而增加,y=aDb Hc为该地区人工樟子松林叶量、枝量、干量和全树生物量的最优模型。     

Cortical monoterpene variation in natural populations of Pinus sylvestris in Sweden

Cortical oleoresins were obtained from 10 natural populations of Pinus sylvestris L. from different geographical localities. Gas chromatography was used to determine quantities of individual monoterpenes. Considerable variation was found in monoterpene composition among different populations. High proportions of limonene occurred in greater percentages in trees of northern origins, while high sabinene was frequently found in southern trees. Mean proportions of limonene and sabinene in the populations were clinal with latitude. For some monoterpenes, variation coefficients as a measure of variability within populations appeared to be clinal with latitude. 85.4% of the variance in monoterpene composition was found within populations and 14.6 between populations. Discriminant analysis differentiates populations from different geographical localities into different groups. The differences in monoterpene patterns between adjacent populations were statistically nonsignificant. It is recommended that monoterpene composition be used for more general study of genetic variation, geographical distinction between different populations and seed certification purposes.     

呼伦贝尔沙地樟子松基地建设

呼伦贝尔沙地樟子松分布面积较广,有大面积的疏林地,具有天然落种更新能力,发展潜力巨大。在樟子松基地建设中以封育为主,营造樟子松防风固沙林,强化工程建设后期管护,巩固樟子松基地建设成果,确保樟子松资源总量可持续健康发展。