荒漠景观拟步甲科昆虫多样性及其对生境的指示作用

本研究在宁夏灵武白芨滩国家级自然保护区北部荒漠景观下的磁窑堡地区,选取典型荒漠草原区(DS)、人工柠条林种植区(CCL1,CCL2)及流沙人工封育区(SDE1,SDE2,SDE3)3类生境共6块样地,于2010年4月至8月以巴氏罐诱法采集该地区拟步甲科昆虫,研究该地区拟步甲科昆虫多样性及其对生境的指示作用。结果共获得标本3406头,计12属22种,其中东鳖甲属Anatolica和小鳖甲属Microdera为优势属,波氏东鳖甲Anatolica potanini Reitter、阿小鳖甲Microdera kraatz alashanica Skopin、小丽东鳖甲Anatolica amoenula Reitter和尖尾东鳖甲Anatolic amucronata Reitter为优势种。在流沙人工封育区的SDE1样地物种丰富度指数、均匀度指数和多样性指数最高,SDE3样地个体数量和优势度指数最高;人工柠条林种植区的CCL1样地个体数量最低。聚类分析结果表明流沙人工封育区与荒漠草原区、人工柠条种植区在物种组成及生境相似性方面差异较大。利用指示值法确定不同生境的特征指示种类,结果显示波氏东鳖甲、谢氏宽漠王Mantichorula semenowiReitter、尖尾东鳖甲可作为流沙封育区特征指示种;突角漠甲Trigonocnera pseudopimelia(Reitter)、中华砚甲Cyphogenia chinensis(Faldermann)和纳氏东鳖甲AnatolicanuretiSchusteretReymond可作为荒漠草原特征指示种;蒙古漠王Platyope mongolica Faldermann、多毛宽漠甲Sternoplax setosa setosa(Bates)、克小鳖甲Microdera kraatzi(Reitter)是生境恢复的监测种;小丽东鳖甲Anatolica amoenula Reitter等种类可作为生境退化的监测种。     

荒漠地区柠条种实害虫对寄主斑块质量与格局的反应

以宁夏中东部荒漠区为景观背景,选择人工固沙次生林地、流动风积沙地和沙壤土质丘陵地3种生境类型共18块天然或人工种植的柠条林斑块,研究了柠条豆象、豆荚螟和柠条种子小蜂3种柠条种实害虫对寄主植物斑块质量、斑块面积和空间格局的反应.结果显示:3种柠条种实害虫对寄主植物的为害率与斑块质量、斑块格局和昆虫自身迁移能力有关.对斑块质量的反应受到斑块尺度大小的影响,在不同的生境类型间,种实害虫的为害率差异显著(P<0.05),以人工固沙次生林地的为害率最高,其次为沙壤土质丘陵地,流动风积沙地相对较低.在小斑块格局中,柠条种实害虫数量的发生与寄主植物斑块的面积、破碎化程度存在一定的相关性,斑块面积减少、生境破碎化程度增加能够降低移动能力较强的豆荚螟(r=0.365)的为害率,而对移动能力较弱的柠条豆象(r=0.160)、柠条种子小蜂(r=0.193)则没有明显影响.斑块边缘效应强度和景观斑块周边资源互补对种群密度具有正相关的影响.     

荒漠景观地表甲虫群落边缘效应研究

本文以宁夏白芨滩国家级自然保护区两种典型的边缘类型:荒漠草原-人工固沙柠条林(边缘类型Ⅰ)和荒漠草原-固定半固定沙地(边缘类型Ⅱ)作为研究对象,以距离梯度(25 m)的形式设置样点,主要采用巴氏罐诱法探讨边缘效应对其地表甲虫群落多样性的影响。本研究共采集到地表甲虫标本6 760头,分属于19科68种,其中样地Ⅰ采集到2 045头,样地Ⅱ采集到4 715头。统计发现,拟步甲科昆虫占样地Ⅰ的70.46%、样地Ⅱ的81.91%,是该地区地表甲虫中的绝对优势类群。边缘类型Ⅰ中,边缘生境地表甲虫的物种数、优势度指数以及丰富度指数均高于相邻生境内部核心区域,而其均匀度指数和多样性指数则低于人工固沙柠条林核心生境。边缘类型Ⅱ中,边缘生境地表甲虫的物种数、丰富度指数以及多样性指数均高于相邻生境的内部核心区域。边缘效应强度分析表明,边缘类型Ⅰ的E H'=0.9958,E C=1.1391,呈负的边缘效应,但负效应很弱,边缘类型Ⅱ的E H'=1.1394,E C=0.5994,呈正的边缘效应,这一结果与边缘地带的环境复杂性和生境异质性有关。     

人工柠条-荒漠草地交错带拟步甲昆虫群落多样性

选取宁夏东部盐池县人工柠条灌丛-荒漠草地交错带为研究样地,以距离梯度形式,利用巴氏诱罐法对拟步甲科昆虫群落多样性进行了调查,研究了边缘效应对拟步甲昆虫群落多样性的影响。共采集拟步甲昆虫1405只,分属8属13种。结果表明,克小鳖甲和弯齿琵甲个体数量分别占总个体数的32.74%和43.27%,为该地区的优势种类。拟步甲昆虫在人工柠条灌丛-荒漠草地交错带的分布可分为3种类型,优势种克小鳖甲和弯齿琵甲属于栖息地广布型,但二者并没有表现出十分均匀的适应性,而且他们在各样带的分布呈显著负相关,克小鳖甲的分布趋向于沙生荒漠环境,弯齿琵甲的分布趋向于柠条灌丛;常见种蒙古漠王、小皮鳖甲的分布偏向于喜好荒漠草地;异距琵甲、奥氏真土甲、网目土甲和淡红毛隐甲的分布则偏向于喜好柠条灌丛。拟步甲昆虫丰富度与Shannon-Wiener多样性沿边缘分别向柠条灌丛和荒漠草地内部降低,个体数量总体上沿柠条灌丛、交错带向荒漠草地内部降低,但各样带差异不显著。从季节动态看,荒漠草地和柠条灌丛物种多样性季节变化相似,3种生境拟步甲活动密度季节变化相似。边缘效应强度分析呈现边缘正效应。CCA排序图显示分类地位相近的物种在生态适应上具有趋同性。多元回归分析表明,植被密度影响拟步甲昆虫群落的优势种和个体数量,植被盖度和高度分别影响拟步甲群落的均匀度和丰富度。主坐标分析(PCo A)排序表明人工柠条灌丛-荒漠草地交错带的拟步甲昆虫群落组成与柠条灌丛内部没有明显分化,但趋于向柠条灌丛生境演替。     

紫胶林-农田复合生态系统地表甲虫多样性——以云南绿春为例

为揭示紫胶林-农田复合生态系统地表甲虫多样性, 于2006-2007年在云南省绿春县牛孔乡采用陷阱法调查了天然紫胶林、人工紫胶林和旱地的地表甲虫群落。共采集标本1 678头, 分别隶属于24科120种, 其中步甲科(Carabidae)和金龟科(Scarabaeidae)种类最丰富, 均占全部种类的12.50%。拟步甲科(Tenebrionidae)个体数量最丰富, 占个体总数的64.48%; 金龟科次之, 占个体总数的17.58%。大多数科的物种数和个体数在不同土地利用生境中的分布没有显著差异, 而步甲科、隐翅甲科(Staphylinidae)、叩甲科(Elateridae)、拟步甲科、瓢虫科(Coccinellidae)和小蠧科(Scolytidae)在不同土地利用生境中的分布有显著差异。天然紫胶林地表甲虫个体数量最少, 物种较丰富, 优势度最低, 多样性最高; 人工紫胶林个体数和物种数均丰富, 优势度和多样性居中; 旱地个体数量最多, 物种最贫乏, 优势度最高, 多样性最低。种级水平的聚类分析体现出人工紫胶林与旱地之间在种类组成上距离较近; 而科级水平的聚类反映出人工紫胶林和天然紫胶林更接近。结果提示, 紫胶林-农田复合生态系统具有区域内土地利用方式多样化的特点; 天然紫胶林在维持地表甲虫多样性水平上具有重要作用, 而人工紫胶林虽具有积极作用, 但仍需进一步恢复。     

生境破碎化对动物种群存活的影响

生境破碎是生物多样性下降的主要原因之一。通常以岛屿生物地理学、异质种群生物学和景观生态学的理论来解释不同空间尺度中生境破碎化的生态学效应。生境破碎化引起面积效应、隔离效应和边缘效应。这些效应通过影响动物种群的绝灭阈值、分布和多度、种间关系以及生态系统过程,最终影响动物种群的存活。野外研究表明,破碎化对动物的影响,因物种、生境类型和地理区域不同而有所变化,因此,预测物种在破碎生境中的存活比较困难。研究热点集中于：确定生境面积损失和生境斑块的空间格局对破碎景观中物种绝灭的相对影响,破碎景观中物种的适宜生境比例和绝灭阈值,异质种群动态以及生态系统的生态过程。随着3S技术的发展,生境破碎化模型趋于复杂,而发展有效的模型和验证模型将成为一项富有挑战性的任务。     

荒漠景观下柠条豆象的空间分布及其对景观斑块格局的反应

柠条豆象Kytorhinus immixtus Motschulsky是危害柠条种子的主要种实害虫之一。本文应用了多个聚集度指标和回归分析方法,研究探讨了柠条豆象卵、幼虫在宁夏盐池、灵武、银川等荒漠景观中11个生境斑块中的空间分布型及种群对景观斑块格局的反应情况。结果表明:在11个景观样地中,柠条豆象卵和幼虫在各种生境斑块中均呈聚集型的负二项分布;卵和幼虫空间分布的Iwao回归方程分别为m*=2.23695+1.64742m(r=0.8273)和m*=2.24418+1.42084m(r=0.8889)、Taylor幂模型分别为logS2=0.51292+1.41118logm(r=0.9344)和logS2=0.59645+1.14736logm(r=0.9786),种群分布的基本成分为个体群,个体间相互吸引,有密度依赖性,聚集主要由环境因素和种间竞争引起的,聚集强度随种群密度的升高而增加。在荒漠景观下,柠条豆象的种群发生与寄主植物的种类、在斑块内的分布格局有着密切的关系,与斑块面积相关性较低(R2=0.1995)。主成分分析显示柠条林生长的土壤类型、生长方式是影响柠条豆象寄生的主要因素。     

科尔沁沙地“生境岛屿”面积对植物物种多样性及其分布格局的影响

气候变化与人为干扰加剧景观破碎化进程,导致产生一系列相互隔绝的"生境岛屿"。本研究以科尔沁沙地流动沙丘18个不同大小丘间低地为研究对象,将丘间低地视为"生境岛屿",探讨"生境岛屿"面积对植物种分布格局的影响,并基于此提出物种多样性保护方案。结果表明:物种对生境破碎化的敏感性不同,第I类物种主要分布在小面积岛屿(如乌丹蒿、芦苇、野豌豆);第II类物种主要分布在大面积岛屿(如胡枝子、画眉);第III类物种主要分布在中面积岛屿(如刺藜、苦参);第IV类物种在大岛、中岛、小岛均有分布(如黄柳);在累加岛屿面积相同时,总物种数为中岛组合组合岛大岛组合小岛组合;沙生植物物种数为组合岛中岛组合大岛组合小岛组合;草甸植物物种数为中岛组合组合岛大岛组合小岛组合;草原植物物种数为组合岛中岛组合大岛组合小岛组合。探讨"生境岛屿"面积对植物多样性及其分布格局的影响将为半干旱沙区植物多样性保护提供理论依据。     

生态保护区外斑块对景观连接度的影响评价

快速的城市化过程带来的生境斑块破碎化及损失会影响物种迁移、捕食等生态活动,对生物多样性构成威胁。然而,现有生态保护区可能无法覆盖其内生物的必要活动范围。生态保护区外的生境斑块对于维持生态过程也具有重要作用,因此识别生态保护区外的关键斑块并加以保护非常重要。以北京市延庆区为研究区,划分两种生境斑块,即核心生境斑块和潜在生境斑块,并基于图论构建生境网络。考虑地表覆盖类型、坡度、人类活动等因素构建生境阻力面。结合未来土地利用类型变化的模拟,研究城市化过程对区域生境网络和景观连接度的影响,选用CLUE-S模型模拟土地利用类型变化的格局。结合生境斑块特征和未来城市土地利用变化情况设计了3种未来生境变化情景。利用连接概率指数(PC)和网络连接度变化率(dI)评价不同生境变化情景下生态保护区外潜在生境斑块的景观连接度重要性,判断保护优先顺序,并分析景观格局变化对不同迁移能力物种的影响。结果表明：生态保护区外的全部潜在生境斑块对维持生境整体景观连接度有最大2.15%的影响,单个潜在生境斑块对维持景观连接度有最大0.28%的影响。此外,景观格局及其变化对不同迁移能力物种的影响差异显著,因此需针对保护物种和城市生境特征设计保护方案,研究区需要优先保护大中型斑块和位于关键位置的小型斑块。为了满足对生物多样性保护的需求,建议在区分生境斑块保护优先顺序时考虑生境斑块对景观连接度的贡献和城市化扩展过程的压力。研究为城市生物多样性保护和生境管理提供了方法参考。     

基于陷阱法采集的河西走廊戈壁荒漠甲虫数据集

戈壁荒漠甲虫多样性对气候变化和人类活动干扰的响应十分敏感,甲虫数量、多样性及其功能性状可用于评估戈壁荒漠生态系统的健康与稳定。戈壁荒漠甲虫分布及多样性月动态变化数据积累可为荒漠生态系统动物多样性保护与维持机制研究提供数据支撑。河西走廊中部是戈壁荒漠主要分布区之一, 2012年研究组在河西走廊中部的甘肃省临泽县北部干旱荒漠国家沙化土地封禁保护区内建立了地表甲虫分布及多样性的长期监测样地。本数据主要汇集了戈壁荒漠地表甲虫物种组成、物种照片、活动节律、数量及功能性状信息数据。该数据集可用于典型荒漠甲虫种属识别、典型甲虫种功能性状比对及其时空分布格局对气候变化及人类活动扰动的响应研究。     

六种藓类植物茎的比较解剖学研究

通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m⁻² s⁻¹. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to P_fr.     

Cause of Senescence of Nine Sorts of Flowers

The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.     

龙胆科药用植物化学成分的研究现状

龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.     

真菌类遗传学分析的知识结构教学

本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.     

Physiological characteristics of various species of strains of carboxydobacteria

Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H₂-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H₂ with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD⁺, FMN⁺, and NAD(P)⁺ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H₂OCO₂+2H⁺+2e^- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation     

The effects of glutamine of the maintenance of embryogenic cultures of Cryptomeria japonica

Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l⁻¹ glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l⁻¹) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.