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大会报告摘要 Global change, climate risks and biodiversity


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www.CNCDiversitas.org

2006
全球变化与生物多样性保护

第七届全国生物多样性保护与持续利用研讨会



论文摘要集


        1. 吉林长春

全球变化与生物多样性保护

第七届全国生物多样性保护与持续利用研讨会

论文摘要集


主办单位:

国际生物多样性计划中国委员会

中国科学院生物多样性委员会

国家环境保护总局自然生态保护司

国家林业局野生动植物保护司

国家教育部科学技术司

国家海洋局海洋环境保护司

中国野生植物保护协会

中国人与生物圈国家委员会

世界自然基金会北京办事处



协办单位:

东北师范大学


大会报告摘要

Global change, climate risks and biodiversity.

Colin Prentice,

(Department of Earth Sciences, Bristol University, Bristol, UK
Email: Colin.Prentice@bristol.ac.uk)

Global environmental changes - climate, atmospheric composition, and land use - all pose threats to biodiversity. Using a "risk analysis" approach developed by my team, I will present probabilistic scenarios (based on the complete set of climate model simulations performed by different groups for the IPCC fourth assessment report) showing the risks of major biome shifts during this century under different scenarios of global warming. Not surprisingly, the risks increase sharply with the degree of warming.

A perhaps more surprising result is that even under "committed" climate change - that is, the amount of climate change that would still occur even if CO2 emissions were to stop immediately - biome shifts are widespread. Since major biome shifts inevitably have consequences for which species of plants and animals are suited to a particular place, this finding has major implications for conservation policy. Adaptation to climate change thus calls for a change in policy from attempted "in situ" conservation to a more dynamic approach. The type of analysis I will present has the potential to assist decision makers in formulating conservation policy under a reasonable range of uncertainty about future changes in climate, as well as providing a graphic way to visualize the extent of the additional risks posed to biodiversity by different degrees of climate change.

大熊猫秦岭亚种的发现及保护对策
万秋红、吴华、方盛国

(浙江大学生命科学学院,浙江杭州 310058)


我国的国宝大熊猫,野外种群数量约1600只,仅分布于毗邻的四川、甘肃和陕西三省的秦岭、岷山、邛崃、凉山、大相岭和小相岭等6个彼此隔离的山系。

面对6个彼此隔离的山系,在国家资金有限的情况下,哪一山系应该优先予以保护,才能最大限度地保护物种的遗传多样性,使主管部门所制定的保护策略与保护计划更加行之有效?而在栖息地的修复工程中,哪些山系之间可以建立绿色廊道,才能既实现大熊猫各山系之间的基因交流,防止近亲繁殖,又能够尽量避免过度的远亲繁殖造成种群的遗传衰退?在人工易地保护中,哪些山系小种群由于不合理的遗传结构而难以通过自身的繁育使种群复壮,亟待通过人类的帮助,使其种源能够得到有效的保护呢?上述诸多的问题,在很长的时间内一直困扰着相关领域的学者和管理者。

不言而喻,解答上述诸多问题的关键,是要弄清楚6个山系的大熊猫之间是否产生了分化;如果已产生分化,分化的程度如何?……

上世纪90年代国外著名学者Avise 等人(1990)和O’Brien等人(1991)分别对Mayr早期所建立的脊椎动物分类学原理进行修改和补充后,提出了确定亚种的三个基本条件:1.具有独立的生态位(空间分布格局);2.具有独立的种群进化历史;3.形态差异与分子差异相一致。基于此,我们对照确立亚种的3个基本条件,开展了大熊猫6个山系之间是否产生了分化这一问题的研究。

首先,3次全国大熊猫栖息地和数量普查的结果表明:秦岭、岷山、邛崃、凉山、大相岭和小相岭6个山系彼此隔离,即6个种群具有独立的生态位,它满足确定亚种的第一个条件。

其次,通过对具有免疫功能的MHC基因DRB位点第二外显子的变异性研究,发现在获得的7个等位基因(DRB1-7)中,秦岭大熊猫具有DRB1、DRB4、DRB5、DRB6和DRB7 5个等位基因,而其它种群的大熊猫则具有DRB1、DRB2、DRB3和DRB4 4个等位基因。其中,DRB5、DRB6和DRB7为秦岭大熊猫所特有,而DRB2和DRB3为其它种群的大熊猫所特有。在DRB位点等位基因的进化上,秦岭大熊猫所特有的DRB6和DRB7 两个等位基因,与猫科动物相同的基因起源于共同的祖先,表明秦岭大熊猫相当古老,比其它种群的大熊猫更为原始。这一结果,表明在6个山系中,秦岭大熊猫满足了被确定为亚种的第二个条件。

第三,通过对6个山系DNA指纹图谱的检测,并分别利用Paup和Phylip软件进行聚类分析,发现秦岭的大熊猫在分子水平上,已达到了亚种之间的分化差异水平,即在晚更新世冰川末期,大熊猫便分割为两个群组,经过约10000-12000年的进化历程,发育为当今的具有亚种水平差异的两个独立群体——秦岭大熊猫和四川大熊猫(含甘肃)。在此基础上,通过对6个山系头骨形态的差异分析,发现秦岭大熊猫与其它山系大熊猫之间的差异,同样达到了亚种分化的差异水平。进一步地,通过胸部和腹部毛色的比较研究,发现秦岭大熊猫与其它山系的大熊猫之间也具有明显的色泽差异。因此,秦岭大熊猫与其它山系的大熊猫之间在形态和分子两方面的差异,是相一致的,满足了确定亚种的第三个条件。

综上结果,我们将秦岭山系的大熊猫,正式命名为秦岭亚种:Journal of Mammalogy, 2005, 86(2):397-402.

为有效地保护大熊猫秦岭亚种,我们从保护遗传学角度,提出了相关的保护对策。
利用野外控制实验研究温带草地生物多样性对全球变化的响应

Biodiversity Responses to Global Change in the Temperate Steppe in Northern China: Ecosystem Manipulative Experiments
万师强

(中国科学院植物研究所,北京 100093)


作为全球变化生态学研究的重要手段之一,野外自然条件下的生态系统控制实验不仅能够比较真实地模拟陆地植物和生态系统对全球变化的响应与适应,而且能够为生态系统模型提供参数估计和模型验证。2005年,中国科学院植物研究所在内蒙古多伦县开展了一项包括模拟放牧、施肥、降水和增温处理的多因子实验,目的在于揭示全球变化对我国北方温带草原生物多样性和生态系统功能的潜在影响。在国家自然科学基金委的资助下,另外两项研究温带草原对全球变化响应的野外实验也于2006年启动;第一项实验的主要目的是探讨由于全球变暖背景下白天和夜间增温幅度的不同对陆地植物和生态系统的特异性影响。第二项实验是在温带草原从东到西的降水梯度上,分别对草甸草原、典型草原和荒漠化草原进行增温和施氮处理,以检验温带草原生物多样性对全球变化的响应是否随资源(水分和氮素)的可利用性而变化。

全球气候变化与植物迁地保护

Climate change and ex situ plant conservation
黄宏文

(中国科学院武汉植物园,中国武汉,磨山 430074)


当今世界正经历着人类历史以来最快速的环境变化,人类关注的焦点是全球气候变化将直接影响地球上的植物及其与之忧戚相关的所有生命形式。基于植物多样性维系的生态系统健康是保证人类生存的根本。

地球上现存约40万种高等维管植物的1/3左右因过渡砍伐等掠夺性的生产方式、城市化进程、环境污染、土地使用变化、外来物种入侵及气候变化等因素影响而濒临灭绝。同时,随着预期本世纪末全球气温逐步上升6˚C,植物灭绝速率将进一步加快,现存植物总数的一半(20万种)将受到威胁(THE GRAN CANARIA DECLARATION ON CLIMATE CHANGE AND PLANT CONSERVATION,2006)。本世纪初全球植物园界针对当今植物多样性急剧消失的严峻形式,于2001年起草了《大加那列岛宣言》并成为世纪之初全球植物多样性保护的纲领性文件和行动的指南。2002年国际植物园保护联盟(BGCI)进一步制定了《植物保护全球战略》得到“生物多样性公约”缔约国大会一致赞同,被认为是生物多样性公约生效以来第一个具有明确时间实施框架的行动计划。《植物保护全球战略》明确提出了至2010年的16个预期目标(Global Strategy for Plant Conservation,2002)。

随着全球气候变化成为国际植物学界关注的热点,全球植物园界经过近两年的酝酿,于2006年4月植物园专家再度汇集在西班牙的大加那列岛以“全球变化与植物园”为主题就植物园的作用、植物资源的价值和灭绝危机管理三个方面进行了全面讨论。据现有研究表明,未来100年在全球气候变化的影响下欧洲大陆的植物在2080年将有 >50%物种受协,同时,高山生态系统中的约60%物种将灭绝(Thuiler et al, 2005; PNAS)。同样,非洲大陆形式同样严峻,研究表明:至2100年因气候变化现有50%物种将失去适宜的生境地(Jon Lovett, et al, 2006)。会议起草了“大加那列岛宣言2-气候变化与植物保护”(The Gran Canaria Declaration on Climate Change and Plant Conservation),制定了全球植物园应对气候变化的迁地保护策略框架。“宣言”充分强调了迁地保护作为植物多样性未来安全的极端重要性。•充分认识和确立“迁地保护”作为保证野生植物安全的核心作用和地位,

即:作为未来植物多样性安全的主要策略保证;作为野外恢复和重返自然计划的基本资源保障;作为人类生计适应气候变化或气候代变迁的基本支撑;加强迁地保育方法的研究,改进迁地保育物种在居群水平的最大遗传多样性的涵盖度,以适应气候变化条件下人类利用植物的未来需求等。“宣言”

确立了应对气候变化的优先研究方向,如:1.加强植物多样性—气候变化模型研究,结合微生境,弄清在全球气候变迁下的潜在的受协物种和潜在的入侵物种;2.生物资源模拟研究,增强对气候变化对生物资源影响的认识;3.部署野外监测计划,评价和长期监测气候变化对植物多样性的影响;4.研究明确将来可能成为保护植物多样性最大化的避乱地(具有多异生境环境的特殊山区)并将这些地区作为就地保护的重要地区优先考虑;5.以植物分布格局及生物学特征资料为基础,评估制定生物多样性迁移廊道的计划等。 同时,“宣言”还确定了在气候变化形式下,目前迁地保护的优先植物类群:无路可迁徙植物类群(mountain tops, low-lying islands, high latitudes and the edges of continents);狭域分布类群

;散布能力弱及长寿植物类群;对极端条件敏感植物;•特殊生境植物;共生或共进化重要类群;对气候变化的生理应答弱的植物类群;初级生产力和生态系统功能的关键类群和人类直接价值和潜在价值类群



生物多样性控制病虫害原理与方法

The principle and method of biodiversity for crop disease and pest management
朱有勇

(云南农业大学,云南昆明 650034)


1)简要介绍利用生物多样性控制病虫害理论和技术成为国际研究热点的背景及发展趋势。

2)介绍该理论技术主要科学原理及其方法特点,主要介绍遗传多样性和物种多样性控制病害的重要作用因素。

3)介绍理论技术的应用前景及其影响。


生物多样性研究进展

Challenges and Opportnities in Biodiversity Science

马克平


(中国科学院植物研究所, 北京 100093)

由于经济的快速发展,生物多样性正面临巨大的威胁。对于生物多样性科学而言,充满了机会与挑战。生物多样性缔约国大会向188个缔约方和全世界关心环境与发展的人们提出了2010年生物多样性保护目标,简称“2010 target”,即基本遏制生物多样性锐减的态势。围绕这样的目标科学界开展了大量的卓有成效的研究与保护工作。为了让大家对于国际上生物多样性研究的热点问题有一个基本的了解,我将有关的进展进行简要介绍,特别是去年11月在墨西哥召开的Diversitas 第一次开放科学会议上了解到的情况。概括起来大概有下列几个方面:全球变化对生物多样性的影响;生物多样性热点地区与受威胁现状评价/保护生物地理学;生态系统服务价值定量评估;生物多样性的生态系统功能;生物多样性信息学;Tree of Life/谱系生物信息学;谱系生物地理学;生物的快速鉴定(远程/分子)/Barcode of life;生物多样性调查与监测。



专题1 生物安全与遗传资源

菝葜复合种(Smilax china complex)物种分化的遗传基础研究



Studies of Speciation and differentiation on Smilax china complex
孔航辉 王艾丽 傅承新

(浙江大学生命科学学院,植物系统进化与生物多样性实验室 杭州 310059)

菝葜(S. china L.)为菝葜属在亚洲的广布种,是菝葜属China组的一个代表类群。根据以前的形态、核型性状及分布研究,我们提出了菝葜复合种的概念,认为广布种菝葜(染色体具有从2X~6X的不同倍性的连续变化)和小果菝葜、三脉菝葜、红果菝葜和硫球菝葜等近缘种一起,构成一个以我国亚热带地区分布为主、延伸到日本岛屿、中国台湾和支那半岛的菝葜复合种 (S. china complex)。研究发现广布种菝葜种内形态变异较多,且与近缘种种间界限模糊,分布上存在重叠现象,关系复杂;本研究从等位酶分析方法,利用nrDNA ITS、cpDNA matK和trnT-L等序列数据对菝葜复合种的起源和分化进行了初步的研究。

等位酶分析认为,同组的黑果菝葜不属于菝葜复合种内,确认了菝葜在神农架的唯一一个2倍体居群,揭示了该2X群体与二倍体的小果菝葜和三脉菝葜之间的亲密关系,认为它们很可能是菝葜四倍体、六倍体的亲本之一,或者至少存在多次基因渗透。酶谱揭示广布种菝葜的二个四倍体居群——广西和贵州居群是异源多倍体的,推测其亲本是菝葜的二倍体居群和三脉菝葜。等位酶分析支持菝葜复合种内的多倍体是多起源的,即多倍体形成经历了多次不同基因型亲本的基因渗入,产生了一个多变的多倍体基因型。

对广布种菝葜 (S. china )的12个居群及6个近缘种:红果菝葜, 长托菝葜, 粗糙菝葜, 小果菝葜, 三脉菝葜和S. biflora的DNA 序列(ITS, matK和trnT-L)分析研究结果表明:ITS1长度变异在202-233bp,ITS2长度变异为235-247bp,ITS1的信息位点(45)多于ITS2(23)。matK中保守位点为1201个,99个位点有差异,132个性状为信息位点。trnT-L的长度变异为895-1010bp,986个为保守位点,信息位点为28个。各个分子标记都支持菝葜复合种为单系类群。在联合数据分析中,菝葜复合种分成2个分枝。第一个分枝包括粗糙菝葜, 红果菝葜和菝葜的金佛山居群并得到100% BS支持,第二分枝包括菝葜复合种的其它类群。第二分枝中菝葜的桂林居群自成一亚枝。系统发育分析支持菝葜多倍体居群的多次起源,桂林居群和金佛山居群可能是异源多倍体;认为菝葜的二倍体居群,小果菝葜和三脉菝葜是该复合种的祖先种;北美的单一伞形花序木本种与亚洲菝葜组(含菝葜复合种)是姐妹群关系。
我国濒危畜禽遗传资源保护的现状与对策

Status and Strategy of Endangered Domestic Animal Genetic Resources Preservation in Our Country

刘丑生


(全国畜牧兽医总站畜禽牧草种质资源保存利用中心,北京 100094)
本文分析了我国畜禽遗传资源濒危的现状、家畜遗传资源濒临灭绝的特点,总结了我国在畜禽遗传资源保护方面的法制建设、资源保护体系建设和在畜禽遗传资源保护科学研究方面的成果,提出了我国濒危畜禽遗传资源保护和利用的对策。
植物园迁地保护中的遗传风险评价-以濒危植物秤锤树为例

Potential risk of hybridization in ex situ collection of the endangered plants in botanical garden- a case study for Sinojackia xylocarpa

姚小洪


(中科院武汉植物园,武汉,430074)
  迁地环境下近缘种间的自然杂交会破坏迁地保护濒危种的遗传完整性,同时,迁地条件下距离相临近的同属种间的自由授粉也可能使用于恢复和回归引种的种子和幼苗造成遗传污染。秤锤树和狭果秤锤树是中国特有濒危种,在自然条件下它们的分布区不相互重叠,由于同时都被迁地保护在武汉植物园中,因此可能存在潜在的杂交风险。本研究从2003到2005年连续三年进行了人工授粉和传粉生物学初步研究来探讨两种植物是否能够进行杂交。实验结果表明在武汉植物园中,两个物种的花期重叠时间为14—20天、在整个开花季节具有相同的传粉昆虫且种间不存在花隔离机制,因此,可能存在种间花粉的传播、遗传渐渗、栽培种的遗传完整性的丢失的现象。人工授粉结果证明这两个种间杂交能够结实且产生种子。由此可见,种间不存在传粉后障碍,空间隔离是种间杂交的重要的障碍。因此,对于花期相近、具有相同的传粉昆虫的同属种而言,空间隔离是使自然杂交最小化所应该考虑的因素。鉴于此,濒危植物在进行回归引种的种源选择时必需防范这种潜在的杂交风险。
烤烟种质资源的遗传多样性分析

Genetic Diversity of Flue-cured Tobacco (Nicotiana tabacum L)

许美玲


(中国烟草育种研究南方中心 云南省烟草科学研究所,玉溪,653100)
为加快优质、多抗烤烟新品种选育的步伐和提供具有不同农艺性状的烤烟种质资源供育种者选择利用,对700多个烤烟种质资源的植物学性状、主要农艺性状统计,并与主要栽培品种进行比较和分析,结果表明:烤烟种质资源的遗传多样性较为丰富,主要表现在株型、叶形、茎叶角度、叶耳、叶尖、株高、叶数、腰叶的长和宽等多方面的差异和多样性。各性状指标的多样性分布有一定的规律性。多样性的烟草种质资源可供育种者选择适合于不同育种目标需要的亲本材料。本研究可为培育优质抗病的烤烟新品种提供一定的理论参考依据和有重要价值的烤烟种质资源材料。

喜旱莲子草生态型对生物防控的不同反应与其遗传多样性不相关性



Genetic diversity of alligator weed ecotypes is not the reason for different responses to biological control
李静 叶万辉

(中国科学院华南植物园,广州 510650)


莲草直胸跳甲能够有效地控制水生型喜旱莲子草,但对陆生型的控制能力却很小。为了了解这一差异的可能的遗传背景,我们用简单插入序列重复(ISSR)分子标记检测了不同生态型的喜旱莲子草的遗传多样性。结果显示,一方面同一生境下生长的种群不具有种群内和种群间的遗传差异,另一方面,不同生境下生长的种群即陆生种群和水生种群间也没有遗传差异。因此,我们认为遗传变异不是导致我国不同生态型喜旱莲子草对莲草直胸跳甲不同反应结果的基本原因。结合以往的研究和观察,莲草直胸跳甲在不同生态型喜旱莲子草上的不同的化蛹能力可能和喜旱莲子草茎秆直径的表型可塑性相关,而与遗传因子之间没有联系。
红河大翼橙的遗传多样性分析

Genetic Diversity of Citrus hongheensis
杨杨

(中国科学院昆明植物研究所生物多样性与生物地理重点实验室,昆明 650204)


在100个随机引物中选取了13个可扩增出稳定且特异性高的引物,对云南特有柑橘种类——红河大翼橙6个居群的120个个体进行了ISSR扩增,实验结果表明,红河大翼橙居群之间表现出较高水平的遗传分化,为柑橘遗传资源利用和保护方面提供了分子水平上的依据。
环渤海区域林蛙的多样性

Diversity of wood frogs in the region around Bohai
李丕鹏 陆宇燕

(沈阳师范大学化学与生命科学学院,沈阳110034)


我们对环渤海区域8个地区的林蛙物种多样性进行了调查,共采集到林蛙6种,并对它们进行了核型等实验研究和形态学观察,发现桓仁林蛙和昆嵛林蛙的核型在黑龙江林蛙种组比较特殊,前者是2n=24,后者是2n=6。通过对中国林蛙、镇海林蛙和峨眉林蛙模式标本以及环渤海区域的标本进行测量和比较,可以看出,由南向北中国林蛙体型逐渐增大;山东徂徕山的长肢林蛙种组物种具有镇海林蛙和峨眉林蛙的中间过渡性状,可能为一个隐存种。黑龙江林蛙种组的4个物种呈间断地分布于我国环渤海区域、东北和新疆,其中黑龙江林蛙和桓仁林蛙与东北林蛙呈重叠分布。而分布于山东的中国林蛙、昆嵛林蛙和徂徕山的林蛙则呈现出彼此隔离的分布格局。东北林蛙和中国林蛙在分布上可能相互重叠,值得进一步深入研究。
生物入侵对自然保护区的危害

The Damage of Invasive Species in Nature Reserves
赵 衡

(西南林学院保护生物学学院,昆明 650224)


外来生物入侵已成为全球生物多样性减少的第二大原因,对人类健康、经济发展和社会文化等方面都产生了较大的影响。前人的研究结果认为自然保护区生态系统和物种受到人为保护,是生物多样性较完整的区域,外来种不易在这些环境中形成危害,但是,近年来关于外来种危害自然保护区的报道越来越多,人们应该对外来种的认识提升一个高度。本文从外来种的入侵途径出发,介绍了外来入侵物种对自然保护区的危害现状,特别是紫茎泽兰、薇甘菊、互花米草等外来恶性杂草,以及外来有害昆虫等对自然保护区已经产生了巨大的危害。外来种对自然保护区的危害直接体现在排挤土著种,竞争生存资源,破坏原有生态系统,以及在经济、文化等方面产生负面影响。最后,综合以往的研究经验提出了预防和保护建议。
Genetic diversity and population structure in Vallisneria spinulosa (Hydrocharitaceae), a dominant submerged macrophyte in lakes of the middle-lower reaches of the Yangtze River
陈磊

(中国科学院武汉植物园,武汉 430074)


Vallisneria spinulosa is a dominant submerged macrophyte in lakes of the middle-lower reaches of the Yangtze River. Allozyme variation, clonal diversity and population genetic structure were investigated for a total of 396 individuals sampled from 10 extant populations. V. spinulosa maintained high levels of genetic variation both at the species and at the population level. Although aquatic macrophytes commonly exhibit low genetic variation within populations, the obligately outcrossing mating system of V. spinulosa, pervasive gene flow resulting from seed dispersal, and regular sexual recruitment likely account for the high levels of diversity maintained within populations. A significant excess of heterozygotes was observed across all populations, suggesting that selection for heterozygotes may have occurred in this species. All V. spinulosa populations contained high clonal diversity with a mean proportion of distinguishable genotypes of 0.57 and a mean Simpson’s diversity index of 0.95, indicating that populations were founded sexually or that successful seedling recruitment occurred after initial colonization. Partitioning of genetic diversity revealed a surprisedly low population differentiation (GST = 0.059) as compared to other hydrophilous angiosperms. No evidence of isolation-by-distance was found, suggesting that gene flow was not restricted geographically. The UPGMA cluster analysis revealed that several widely separated populations grouped together, suggesting the long-distance gene flow among populations. The high vagility of V. spinulosa and extensive hydrologic connectivity among populations facilitate long-distance seed dispersal. Historically, frequent water-mediated long-distance seed dispersal among populations probably has resulted in pattern of population genetic structure in V. spinulosa observed in lakes of the middle-lower reaches of the Yangtze River.
东亚黄精叶钩吻属(Croomia)遗传多样性与亲缘地理学研究

Genetic diversity and phylogeography of Croomia
李恩香 邱英雄 傅承新*

(浙江大学,植物系统进化与生物多样性实验室、国家濒危动植物种质基因保护中心 杭州 310059 )



黄精叶钩吻属是单子叶纲百部科(Stemonaceae)植物,共有3种,即C. japonica Miq., C. heterosepala (Bak.) Oku. and C. pauciflora (Nut.) Tor.。本属植物为东亚-北美间断分布,且花为4基数,这些特征引起了植物学家及植物地理学家的广泛兴趣。通过ISSR标记对来自10个C. japonica居群,6个C. heterosepala居群和1个C. pauciflora(美国)居群共303个个体的研究,发现种内居群间遗传变异大于居群内的变异,特别是C. japonica居群间出现很大的分化,甚至有的居群间遗传距离大于种间的遗传距离。C. japonica居群的多样性指数与繁育系统(花粉与胚珠的比例)密切相关。通过cpDNA (trnL-F和atpB-rbcL) 单倍型的研究,发现单倍型的分布与地理间有密切的关系,推测Coomia在东亚大陆与东海---日本岛屿分离前曾广泛分布, 而最近的冰期使它们退缩在我国的天目山---黄山一带,以及日本的九州、四国、静冈县和大阪与、歌山县地区,成为可能的冰期避难所。根据ISSR和cpDNA的结果,可以认为C. pauciflora是较原始的种,而C. heterosepala可能是C. japonica的一个后裔种。由于主要的遗传变异出现在居群间,建议在进行保护时要尽可能保护多的居群。
Patterns of Genetic Variation in Swertia przewalskii, an endangered endemic species of the Qinghai-Tibet Plateau
Shilong Chen (陈世龙), Defang Zhang (张得芳), Shengyun Chen (陈生云), Dejun Zhang (张得钧), and Qingbo Gao (高庆波)
Swertia przewalskii Pissjauk. (Gentianaceae), is a critically endangered and endemic plant of the Qinghai-Tibet plateau in China. It is distributed only in the area of the Qilian mountains in the northeastern Qinghai-Tibet plateau. S. przewalskii grows on marsh, rocky crevices, and scrublands at altitudes between 2970 m and 4200 m. According to our expedition during the twentieth century, the populations of S. przewalskii were found in all gorges of the Qilian mountains before 1980. At present, only three populations exist. Many populations of this species have become extinct in the last two decades. The threats to the species are related to grazing and local farming activities as well as overcollection. In addition, S. przewalskii has been used by Tibetans as a traditional herbal remedy to treat hepatitis and cholelith, because this species contains some active constituents such as mangiferin, swertiamarin, swertisin, oleanolic acid, and three xanthones. RAPD and ISSR analyses were carried out to assess the extent of genetic variation in the remaining three populations. A total of 63 individuals were analyzed, and PPB was 94 % (156 bands) for RAPD and 96 % (222 bands) for ISSR. A pairwise distance measure calculated from the RAPD and ISSR data was used as input for analysis of molecular variance (AMOVA). AMOVA indicated that a high proportion of the total genetic variation (52 % for RAPD and 56 % for ISSR) was found among populations; pairwise ΦST comparisons showed that the three populations examined were significantly different (P < 0.001). The significant genetic differentiation was found based on different measures (AMOVA and Hickory B) in S. przewalskii (0.52 on RAPD and 0.56 on ISSR-0.4317 on RAPD and 0.3895 on ISSR). The differentiation of the populations corresponded to low average gene flow (0.33 based on RAPD and 0.39 based on ISSR). Our results indicate that genetic diversity is independent of population size. We conclude that although sexual reproduction and gene flow between populations of S. przewalskii are very limited, they have preserved high levels of genetic diversity. The main factors responsible for the high level of difference among populations are the isolation and recent fragmentation under human disturbance. Considering that most remnant populations are getting smaller as a result of human disturbance, however, it is quite possible that the process of habitat fragmentation will lead to a loss of genetic diversity by dramatically increasing mating opportunities between relatives within small populations. The observed strong genetic differentiation among populations of S. przewalskii indicates management for the conservation of genetic variability in S. przewalskii should aim to preserve all three populations. Because there are not any management actions that are already in practice, clearly conservation action is urgently required to safeguard remaining populations of S. przewalskii. Given the genetic differentiation among populations recorded here, any in situ conservation strategy should aim to include populations from the range of S. przewalskii, if the full breadth of genetic variation within the species is to be conserved. Moreover, the participation of local people is necessary for an effective in situ conservation programme, involving protection from browsing by yak or sheep and development of sustainable harvesting approaches. For a species under such a severe degree of threat, ex situ approaches may also be appropriate as part of an overall conservation strategy. As the present study has recorded a high degree of genetic differentiation between wild populations, there is clearly a need for further sampling from as many plants as possible. The development of the ex situ population in cultivation in the gorges of Qilian mountains could be of value to an overall conservation strategy for S. przewalskii. Such a strategy could potentially include restoration of populations which have been degraded, through reintroduction of plant material. However, any reintroduction must be undertaken at sites which are themselves protected, such protection is lacking at present.
Chloroplast phylogeography of Dipentodon sinicus (Dipentodontaceae) in southwest China and north Vietnam
QING-JUN YUAN * ZHI-YONG ZHANG SONG GE and HUA PENG*

(* Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, the Chinese Academy of Sciences, 650204, Kunming, Yunnan, China

Laboratory of Systematic and Evolutionary Botany, Institute of Botany, the Chinese Academy of Sciences, 100093, Beijing, China

Agricultural College, Jiangxi Agricultural University, 330045, Nanchang, Jiangxi, China

Graduate University of the Chinese Academy of Sciences, 100049, Beijing, China)
The evolutionary history of plants in southeast Tibetan Plateau (i.e. Hengduan Mountains) might be one of the most complex around the world because of the extremely complex topography and climate in this area. We conducted a phylogeographic study using chloroplast sequences on a monotypic genus Dipentodon with an attempt to test how historical events such as tectonic movements, orogenesis and Quaternary climate oscillation shaped the plant population structure in this area. The results showed that D. sinicus had high genetic diversity (hT=0.902) and high genetic differentiation (NST=0.987 and GST=0.948). The high genetic diversity may be attributed to its long evolutionary history, highly diverse habitats and outcrossing life form. The seed dispersal via elasticity, complex terrains in the distribution range of D. sinicus and the influence of human activities could account for the high genetic structure in this species. Nested clade analysis supported that allopatric fragmentation induced by orogenesis could explain the highly differentiated structure, especially in southeast Tibetan Plateau. However, the haplotype network did not reflect the geographical distribution of this species, as geographically approximate Dian-Qian-Gui clade and Yungui Plateau clade were the most strongly differentiated. We hypothesized that tectonic movement of northwest Yunnan might be the main reason for this phylogeographic pattern. In addition to plate movement and orogenesis, Quaternary climate oscillation also played an important in shaping the phylogeographic pattern of D. sinicus. The results of this study will provide additional insights into the evolution and conservation of biodiversity on Tibetan Plateau and adjacent areas.
Ecological risks caused by introduced insects –The case of European bumblebee and exotic stag beetles-
Koichi Goka & Masahiro Yoneda

(National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053, Japan.)


We have introduced a lot of exotic species, and some of them have come to be invasive alien species. Invasive alien species would cause many ecological impacts on the native species. Don’t you think “Increase of the exotic species in Japan will produce rather good results because biodiversity will increase”? The answer should be NO. The locality of genetic constitution and fauna created through long time evolutionary process support the global biodiversity. However, the artificial transportation of many species between incredible far places for an incredible short time will cause homogeneity of gene and fauna everywhere, which will result in breakdown of global biodiversity.

We here report the case of introduction of the European bumblebee Bombus terrestris which is used as pollinator of agricultural crops, and the case of exotic stag beetles sold as pet in Japan. The market size of these introduced insects has came up to be over 1 billion dollar now in Japan. Here we will show our data of the study for ecological risks of these alien species through competition, genetic introgression and bringing alien parasites. And also, we would like to discuss about economic and social aspects driving the invasive alien species problem.



Present situations of bumblebee pollination in tomato greenhouse in Japan.
Masahiro Yoneda & Koich Goka

(National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-0053, Japan.)


Commercial colonies of the European bumblebee, Bombus terrestris, have been imported for the pollinating agent to vegetable crops in green houses in Japan since 1991. The bee is apparently an effective pollinator for tomato in the houses and can contribute sufficient reduction of working time for farmers, the annual number of hives used for the pollination has increased to 70,000 in 2004. Beside such useful aspects of B. terrestris, the bee has another aspect of an exotic invasive alien species (IAS). Since the ecological niche of B. terrestris is potentially overlapping with that of the Japanese native bumblebees , it is considered that it will disrupt the co-evolved native pollinating systems between the native bees and endemic flora in Japan. Some ecologists have claimed that, instead of using an exotic B. terrestris, pollinating method using native bumblebees should be developed and progressed for pollinations of crops in greenhouses in Japan.

However, there are still some controversies in using the native bumble bees for pollinating; it tend to be considered that the native bees should be ecologically safety than the exotic species, but the mass transportation of manufactured bees, regardless of alien or native species, will disturb the native ecosystem if they would be used under un-controlled conditions.

The Ministry of Environment in Japan enacted a new law “Invasive Alien Species Act” for restricting invasive alien species in 2005, and the European bumblebee has been defined as invasive and to be restricted in this law. This situation will accelerate the increase of use of the commercial native species.

Here, we will introduce the present situation of bumblebee pollination in Japan and the response of the farmers to the new restriction for the bees.


入侵植物薇甘菊的化感作用
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