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1.
云南松天然林分遗传增益研究 总被引：3，自引：0，他引：3
调查了永仁县白马河林场云南松优良林分子代测定试验林树高和地径，估算优良林分的遗传力和遗传增益。结果表明：天然云南松优良林分子代林树高生长量的遗传力为87．9％，与对照相比遗传增益为5．7％；地径生长量的遗传力为52．6％，遗传增益为8．6％。 相似文献
2.
以中国沙棘(♀)和外域沙棘(♂)为亲本,开展远缘杂交试验,在杂种子代生长性状遗传变异分析的基础上,按完全随机区组设计营建子代测定林,综合分析子代遗传力、遗传增益和杂种优势等遗传参量的遗传效应。结果表明:沙棘杂交子代的遗传力和杂种优势较强,遗传增益较高,树高和地径2个生长性状较中国沙棘分别提高50.29%、26.28%,棘刺数量减少276.47%;果实纵径、横径及单果质量3个果实性状的遗传力分别为0.98、0.98、0.99,遗传增益分别为4.82%、4.93%、2.93%,超亲优势分别为65.59%、51.38%和135.64%,遗传效应显著。 相似文献
3.
马尾松自由授粉家系产脂力遗传变异及选择 总被引：1，自引：0，他引：1
在福建省大田桃源国有林场,分析了马尾松高产脂初级种子园自由授粉子代18 a林龄时产脂力和生长性状的遗传变异规律和遗传相关性。结果表明:产脂力家系遗传力和单株遗传力分别为0.5891和0.6078;树高、胸径和单株立木材积家系遗传力介于0.2999~0.3817间,单株遗传力介于0.2033~0.2865间;产脂力与树高、胸径和单株立木材积呈高度正向遗传相关,遗传相关系数分别为0.761、0.884和0.930。对产脂力进行选择时,树高、胸径和单株立木材积的间接选择响应分别达到0.945、1.209和1.303,在获得产脂力较高遗传增益的同时,可间接获得较大生长性状遗传增益。在遗传变异及遗传相关分析基础上,筛选出高产脂家系8个、单株10株,入选的家系平均产脂力、单株立木材积、胸径和树高遗传增益分别为12.32%、4.19%、2.06%和1.07%。入选的单株平均产脂力、单株立木材积、胸径和树高遗传增益分别为58.05%、18.02%、8.38%和3.14%。 相似文献
4.
为找到适合冀北山地生长环境的优良杂种落叶松,以河北省木兰围场国有林场管理局龙头山国家重点落叶松良种基地的杂种落叶松子代测定林为对象,通过野外调查的方法,对胸径、树高和材积的变异程度、生长量进行比较研究,对遗传力和遗传增益进行估算,结果表明:各家系胸径、树高、材积生长量差异显著,其中,材积、胸径的变异幅度较大,树高变异幅度较小,三者变异系数分别为0.42、0.26和0.15;参试家系胸径遗传力为0.83,树高遗传力为0.81,材积遗传力为0.78,通过家系选择可能获得较大的改良效果,初步筛选出5、9、18、11和17等5个家系为优良家系;选出的这5个家系,进行有性繁殖后代,胸径可获得69.51%的遗传增益,树高可获得66.53%的遗传增益,材积可获得67.59%的遗传增益。 相似文献
5.
通过林分调查,对11 a林龄41个家系闽楠优树子代测定林的树高、胸径、冠幅生长和通直度、分枝度指数进行测定,结果表明:不同家系树高5. 55～8. 90 m,胸径6. 92～11. 91 cm,单株材积0. 014 671～0. 050 397 m~3,差异均达到极显著水平,树高遗传力0. 872 5,胸径遗传力0. 791 7,单株材积遗传力0. 855 7;通直度指数3. 04～4. 86,差异达到0. 1显著水平;冠幅2. 15～2. 81 m、分枝度指数3. 14～3. 90,差异均未达到显著水平。以单株材积生长为依据,选出8个速生优良家系,其树高8. 22～8. 90 m,遗传增益7. 62%～15. 46%;胸径10. 86～11. 91 cm,遗传增益11. 62%～20. 40%;单株材积0. 041 936～0. 050 397 m~3,遗传增益32. 20%～55. 97%,相比6 a林龄选出的9个优良家系重复入选3个,8 a林龄选出的8个优良家系重复入选6个;选出30个速生优良单株,其树高8. 3～11. 0 m,遗传增益4. 22%～19. 62%;胸径12. 0～16. 3 cm,遗传增益19. 28%～52. 06%;单株材积0. 059 388～0. 111 401 m~3,遗传增益53. 40%～150. 05%;相比6 a林龄选出的30个优良单株重复入选14个。 相似文献
6.
经对5年生杉木无性系试验林中36个无性系的树高、胸径、材积3个性状进行分析,结果表明:各性状无性系间差异极显著,且有较高的重复力和中等变异系数;生长性状间有较密切的遗传相关关系,以生长性状为基础,初选出6个较速生的无性系,其平均材积对照比较,现实增益为92.08％,遗传增益为71.34％。 相似文献
7.
研究了15年生水曲柳自由授粉家系的子代测定林,用方差分析对树高和胸径进行了家系差异的显著性检验,估算了遗传力和遗传增益.结果表明,水曲柳优树子代之间的遗传品质有显著差异,优树树高的家系遗传力和单株遗传力分别为0.489、0.644,优树胸径的家系遗传力和单株遗传力分别为0.437、0.538.在育种工作中,可根据实际需要,采用不同的选择强度,利用不同的优良家系. 相似文献
8.
不同林龄枫香子代性状变异与家系选择 总被引：5，自引：0，他引：5
对布设在安徽祁门县的首批84个枫香子代测定林，分析比较了9年生与3年生两个不同林龄胸径、树高性状的遗传力和遗传增益等参数，并开展了优良家系选择。结果表明不同时期入选的家系名称、数量及名次出现较大差异，大部分家系胸径、树高性状的家系遗传力、单株遗传力及遗传增益等参数估值，表现为随林龄增大而降低。研究结果为枫香良种选育的适宜林龄提供了参考依据。 相似文献
9.
火炬松半同胞子代配合选择的遗传增益估算 总被引：12，自引：1，他引：12
以半同胞子代为材料,开展火炬松生长性状的评价并进行配合选择,在估算3种遗传力的基础上,估算配合选择的遗传增益.子代测定林分别建于广东英德(24°15'N,113°45'E)和浙江富阳(30°15'N,119°58'E)2个地点,包含24个共同家系,均来自广东英德火炬松种子园.子代林为随机区组设计,6次重复,英德试点为6株行式小区,富阳试点为8株行式小区.以SAS(R)/STAT统计软件的VARCOMP过程用限制性最大似然法估算的方差成分进行遗传力的估算.结果表明:6年生树高单株遗传力、家系内遗传力和家系遗传力分别为0.161、0.129和0.579,胸径遗传力分别为0.075、0.059和0.384,单株材积遗传力分别为0.104、0.082和0.471.用3个公式估算配合选择的遗传增益.在数据严重不平衡的情况下,3个公式估算的结果非常接近,显示了简便的估算公式,即利用家系遗传力和家系内遗传力以及相应的选择差进行估算的公式,具有实用性和可靠性. 相似文献
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11.
浅论植物种质、种质资源、品系和品种的概念及使用 总被引：7，自引：2，他引：5
种质、种质资源、品系和品种等是农学、林学中常用的基本术语,但是长期以来,很多科技文章反映出对这些术语概念模糊,混淆,理解不尽一致。本文以文献为基础,概述了这四个术语的定义:种质指亲代能够传递给子代的遗传物质;种质资源指一切能够繁殖的具有一定种质的生物体;品系指在育种工作中使用的遗传性状稳定一致且来自于共同祖先的一个群体;品种是在生产上推广利用的为某一或某些专门目的而选择的,具有一致、稳定和明显区别的性状,而且经采用适当的方式繁殖后,这些性状仍能保持下来的一些植物的集合体。文章还对这四个术语的异同点和相互关系进行分析,并对术语的使用提出建议。 相似文献
12.
Sustainable development and sustainable forestry: analogies,differences, and the role of flexibility 总被引：2，自引：1，他引：1
Various approaches have been developed to achieve sustainability in forestry, under changing social needs and, consequently,
changing definitions of sustainability. This has led to the confusing situation in which various groups have different understandings
of the meaning of ‘sustainability’. Likewise, the concepts utilized to achieve sustainability, often with a poorly defined
objective, are sometimes not clear and/or inconsistent as a systematic overview regarding definitions and concepts is lacking.
Based on a literature review, this paper discusses related terms such as sustainability, sustained yield management, sustainable
forestry, sustainable forest management and sustainable development: their history, concepts and relationships, from a European
perspective. Finally, flexibility is proposed as a solution to overcome the identified shortcomings at all scales, while focussing
on the enterprise level. The origin of the sustainability concept in forestry was first driven by forest experts, while participatory
elements have been considered since the more recent idea of sustainable development. Since then, much effort has been made
to achieve intragenerational fairness by creating an improved participatory process. Concurrently, the original idea of sustainable
forestry as long-term and future-oriented management, considering future generations’ needs fell behind. An increasing standing
timber volume in Europe and the discussion on climate change brought new interest in how to cope with risks in the context
of pervasive future uncertainties within the scope of promoting sustainable development. Although the consideration of risk
has been concentrated on as a topic in forest science in recent years, studies have mainly focused on the enhancement of forest
resistance against disturbances. However, precaution and risk avoidance alone are probably insufficient to achieve an improved
sustainable development that focuses on intergenerational fairness, as these more defensive approaches may disregard important
management opportunities involved with an uncertain future. A perhaps more promising approach, the idea of future options
and the ability to respond to changing social and biophysical circumstances (i.e. flexibility) as criteria for sustainable
development have only shown a shadowy existence up to now. To further develop the consistency of sustainability concepts,
a shift of sustainability approaches from continuity towards flexibility options is proposed. 相似文献
13.
Oscar García 《European Journal of Forest Research》2011,130(4):671-675
Issues in the development and formulation of forest site-index models are examined, linking the forestry terminology and methods
to standard mathematical concepts. Variability complicates interpretation. Three sources of variation are distinguished: between
sites, within sites, and observation error, with the article focusing mainly on the second one. Two site-index definitions
arising from different views about the variability are contrasted. Modelling based on algebraic difference equations (ADE’s)
is analyzed in detail, relating it to concepts of state space flows used in modern dynamical systems theory. It is shown that,
given a stand current state, ADE’s predict growth rates that are independent of site quality. 相似文献
14.
对“森林资源规划设计调查主要技术规定”和“国家森林资源连续清查技术规定”中名称相同,而内容不同的“有林地、疏林地和灌木林地划分,优势树种,采伐迹地、火烧迹地,森林类别、林种,起源,坡度”和名称不同而内容相同的“自然保护区林、自然保护林,未成林造林地、未成林地,辅助生产林地、林业辅助生产用地”限定词含义等标准中的差异和矛盾等进行了论述和分析,并提出了解决办法。 相似文献
15.
从广义、狭义两个层次,对绿地、园林的概念进行了探讨;并分析了广义绿地、狭义绿地,广义园林、狭义园林间的相互关系。 相似文献
16.
Bryan C. Foster Deane Wang William S. Keeton Mark S. Ashton 《Journal of Sustainable Forestry》2013,32(1):79-108
Certification and principles, criteria and indicators (PCI) describe desired ends for sustainable forest management (SFM) but do not address potential means to achieve those ends. As a result, forest owners and managers participating in certification and employing PCI as tools to achieving SFM may be doing so inefficiently: achieving results by trial-and-error rather than by targeted management practices; dispersing resources away from priority objectives; and passively monitoring outcomes rather than actively establishing quantitative goals. In this literature review, we propose six concepts to guide SFM implementation. These concepts include: Best Management Practices (BMPs)/Reduced Impact Logging (RIL), biodiversity conservation, forest protection, multi-scale planning, participatory forestry, and sustained forest production. We place these concepts within an iterative decision-making framework of planning, implementation, and assessment, and provide brief definitions of and practices delimited by each concept. A case study describing SFM in the neo-tropics illustrates a potential application of our six concepts. Overall our paper offers an approach that will help forest owners and managers implement the ambiguous SFM concept. 相似文献
17.
LIU Li Danish Centre for Forest Landscape PlanningRolighedsvej DK- Frederiksberg C Denmark 《中国林业科技(英文版)》2005,4(1):85-98
1 INTRODUCTIONUrban greening and urban forestry are the often-usedterms today concerning planning trees and vegetationin a city to benefit the city environment and the citylife. Urban greening is defined as the planning andmanagement of all urban vegetation to create or addvalues to the local community in an urban area(Konijnendijk, et al, 2002). Urban forestry is definedas the art, science and technology of managing treesand forest resources in and around urban communityecosystems for th… 相似文献
18.
Helga Pülzl Irina Prokofieva Staffan Berg Ewald Rametsteiner Filip Aggestam Bernhard Wolfslehner 《European Journal of Forest Research》2012,131(1):35-46
In this article, the development and operationalisation of forestry-wood chain indicators within the frame of sustainability
impact assessment are discussed. The analytical framework follows a distinction between indicator definition and selection
in a first phase, and a second operational phase of indicator application in terms of interconnecting material flows, calculation
of chain performance and utilisation within evaluation components. A clear boundary drawing effort in terms of the development
of indicator definitions, related subclasses, and measurement units as well as the creation of conversion factors between
indicator values and individual chain stages supports this. Economic, social and environmental indicators have to respond
to data collection needs on individual process levels (that correspond to sub-divisions of the forestry-wood chain). For the
usage of indicators within evaluation tools, a functional hierarchy has to be provided that supports clear preference elicitation
as well as information on related externalities. In total, this paper aims at demonstrating an enhanced spectrum in the use
of sustainability indicators, and the challenges that arise from a developing and applying multi-functional indicators in
sustainability impact assessment. 相似文献
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20.
生态系统价值评估理论方法的最新进展及对我国流行概念的辨正 总被引：10，自引：1，他引：9
文中指出了我国生态系统价值评估的前期研究中存在的一些错误,如把资产和生产价值混为一谈。指出酿成这些混乱的是一个流行甚广的联合国“千年生态系统评估框架（摘要）”的错误中泽本,以及我国初期研究和案例中的盲目性,刚公布的一项国家标准则有可能继续放大这个错误。文章给出了正确的概念、分类和估价方法以及最新研究进展,并指出了今后的方向。 相似文献