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1.
四川老君山自然保护区不同生境鸟类多样性研究   总被引:3,自引:2,他引:1  
2006年4~5月采用"点样带法"(point transects)对四川老君山自然保护区的鸟类物种组成和种群数量进行了调查,共记录到85种鸟类,分属7目22科。其中,国家级保护鸟类5种,我国特有种13种,优势种4种。把调查区域划分为3种生境:原始林、次生林和人工林,并对各生境鸟类群落的鸟类数量级、鸟类群落的物种多样性、鸟类群落间的相似性进行了比较分析,其结果表明:1)国家级保护鸟类在原始林中最多,次生林中最少;我国特有种则是次生林中最多,人工林中最少。2)鸟类群落Shannon-Wiener物种多样性指数原始林最高,人工林最低。3)原始林和次生林之间的B ray-Curtis相似性指数最高,原始林和人工林之间相似性指数最低。  相似文献   

2.
河南黄河湿地国家级自然保护区不同生境鸟类多样性分析   总被引:1,自引:1,他引:0  
2006年9月~2007年8月,对河南黄河湿地国家级自然保护区鸟类进行野外调查,结合文献共统计鸟类16目53科247种.对山地、滩地、水域、人工林4种生境鸟类物种数、鸟类数量等级、多样性、鸟类群落间相似性进行了分析.滩地鸟类物种数及G指数(属的多样性)和F指数(科的多样性)值均最高.山地和人工林鸟类组成有相似性.  相似文献   

3.
达赉湖自然保护区冬春季鸟类生物多样性与生境的关系   总被引:13,自引:0,他引:13  
2004年4月-5月,利用样带法对达赉湖自然保护区5种主要生境类型中冬春季鸟类生物多样性进行了调查,利用Shannon-Wiener指数和Smith相关性系数分析了这5种生境类型中冬春季鸟类的生物多样性、区系、鸟类的群落组成、群落间的相似性和均匀度。结果表明,古北界鸟类是组成达赉湖鸟类群落的主体(约占冬春季鸟类的86%);芦苇湿地的鸟类多样性接近于芦苇甸的2倍:芦苇湿地鸟类群落的物种多样性最高(Shannon-Wiener指数为1.3001),而芦苇甸中鸟类群落的物种多样性最低(Shannon-Wiener指数为0.6629);芦苇湿地和芦苇甸两鸟类群落组成的相关性指数仅为0.038;从具有共同物种的多少考虑,典型草原和芨芨草原鸟类群落之间的关联较大。  相似文献   

4.
三峡重庆库区不同鸟类群落的物种组成及多样性研究   总被引:2,自引:0,他引:2  
1996~1997年,对三峡工程重庆库区的鸟类群落物种组成和种群数量进行了调查,共调查记录库区鸟类15目48科226种,数量18929只。用鸟类数量级划分、Sorensen相似性指数、Shannon-Wiener指数和Pielou指数分析库区各种生境鸟类群落物组成和物种多样性结果表明:1)库区天然林、人工林、灌草丛和水域生境中鸟类群落的组成与农田生境具有较高的相似性,尤以人工林和农田的相似性最高;2)库区人工林生境鸟类群落物种多样性最高;3)库区由于长期以来人类活动的影响,生境日趋单一,已逐渐形成一种以农田灌丛鸟类为主的鸟类生态系统。  相似文献   

5.
四川嘛咪泽自然保护区不同生境类型鸟类多样性调查   总被引:5,自引:0,他引:5  
2006年4~5月采用样点法对四川嘛咪泽自然保护区的鸟类组成和种群数量进行了调查,共记录到鸟类7目23科105种,数量1948只,其中国家重点保护鸟类6种,我国特有鸟类7种。鸟类区系以东洋界成分为主。对不同生境鸟类多样性的分析结果表明:1)人工林和灌丛草地生境间的鸟类群落相似性指数最高,灌丛草地和原始林之间鸟类群落相似性最低;2)次生林鸟类多样性指数最高,灌丛草地最低;3)原始林内国家级保护鸟类最多,特有种仅次于次生林;4)林中鸟类垂直分布中间层密度最大。  相似文献   

6.
广西山口红树林保护区海陆交错带夏季鸟类多样性调查   总被引:1,自引:0,他引:1  
2011年6~8月采用样带法对山口地区海陆交错带的5种生境的鸟类多样性及群落相似性进行了研究,共记录到夏季鸟类31种,隶属于9目20科。在5种生境的鸟类群落中,红树林生境的鸟类群落Shannon-Wiener指数最高,农田生境的均匀度指数最高,农田生境和红树林生境的鸟类群落相似性指数最高,为0.759,桉树林生境和农田生境的相似性指数最低,为0.240。同时还对海陆交错带不同生境鸟类群落的多样性和相似性方面的问题进行了讨论。  相似文献   

7.
2012年10月至2013年12月对内蒙古乌兰察布地区的鸟类区系及生态分布进行了调查研究。共记录到鸟类215种,隶属于17目48科。其中留鸟42种,夏候鸟101种,旅鸟67种,冬候鸟5种;繁殖鸟143种,构成区系的主体。繁殖鸟中古北界种类有118种,占繁殖鸟总数的82.5%,鸟类区系具有典型的古北界特征。国家Ⅰ级重点保护鸟类有5种,国家Ⅱ级重点保护鸟类有28种。依据地形地貌和植被类型,将该地区划分为湿地、林地、草地、农田、居民区5种生境,其中,湿地鸟类丰富度、多样性指数和均匀度指数最高,居民区鸟类丰富度、多样性指数和均匀度指数最低;优势度指数在居民区最高,在湿地生境中最低。从不同生境鸟类群落间β多样性的变化看,湿地与林地之间物种更替变化最大,群落相似性小;农田与居民区物种更替变化小,群落相似性大,与聚类分析的结果相一致。对该地区不同生境鸟类群落结构及其之间的关系进行了分析,探讨鸟类对栖息环境的选择以及鸟类与环境的关系。  相似文献   

8.
湖北沙湖冬季鸟类群落特征   总被引:6,自引:1,他引:5  
2006年12月—2007年1月采用样线法对湖北沙湖自然保护区鸟类进行了调查,按照生境特征分为芦苇、草甸、农田、水域4个鸟类群落。共记录到鸟类76种,隶属12目28科,占湖北省鸟类种数456种的16.67%。其中,国家Ⅰ、Ⅱ级保护鸟类各1种和10种;濒危物种1种,易危物种2种,稀有物种1种。鸟类群落总体α多样性指数(H′)为2.37,均匀性指数(J)为0.55,优势度(C)为0.17,4个鸟类群落的H′、JC值分别为:1.67~2.44、0.50~0.86、0.11~0.26。β多样性指数分析表明:农田-草甸的鸟类群落相似性指数(Si)最高,为0.74,农田-水域的相似性指数最低,为0.40;Bray-Curtis指数(CN)最高值是芦苇-草甸的鸟类群落,为0.00640,最低值是水域-农田,为0.00022。生境间异质性和人为活动是影响沙湖冬季鸟类群落特征的主要因素。  相似文献   

9.
鸟类群落多样性和相似性的时空格局是认识鸟类环境适应机制的理论基础。在张掖国家湿地公园的保育区,采用样带法研究了冬春季节鸟类群落结构和多样性的异质性。结果表明:1)鸟类多度和丰富度在月际间存在显著差异(P0.05),鸟类多度呈现出先增大后减小的变化趋势,丰富度呈现出先减小后增大的变化趋势,二者最高值分别出现在3月和11月;留鸟、旅鸟和候鸟的多度和丰富度月际间存在显著差异(P0.05),3种鸟类群体多度和丰富度的高峰值出现时间不同步。2)随着月份更替,湿地公园鸟类的Shannon多样性指数呈现先减小后增加的变化趋势,而Pielou均匀度指数则相反,Simpson优势度指数与均匀度指数变化趋势相似。3)不同月份间鸟类群落相似性存在差异,在1月和2月最高(0.923)、11月和4月最低(0.348)。湿地公园时间尺度上鸟类多度和丰富度的错峰分异规律和群落间相似性系数差异性,与鸟类群体的迁徙节律、湿地的食物资源和栖息环境密切相关,反映了鸟类的环境筛选适应能力。  相似文献   

10.
宁夏罗山国家级自然保护区鸟类区系特征及群落结构   总被引:1,自引:0,他引:1  
自2010年10月至2011年12月对宁夏罗山国家级保护区鸟类区系及群落结构进行了调查研究,共记录到鸟类15目46科98属164种,占宁夏已知鸟类总种数的48.81%。其中留鸟51种(31.10%),夏候鸟68种(41.64%),旅鸟38种(23.17%),冬候鸟7种(4.27%)。繁殖鸟119种,其中以古北界鸟类占优势,有88种,占繁殖鸟总数的73.95%;东洋界种15种,占12.61%;广布种鸟类16种,占13.45%。研究发现不同季节、不同生境中的鸟类群落特征差异较大。林地鸟类物种数和多样性指数最高,水域鸟类具有最高的G-F指数。相似性分析显示,山地荒漠草地和废弃村庄的鸟类群落,林地和浅山灌丛鸟类群落,分别具有一定的相似性。春季鸟类群落物种数、G-F指数、多样性指数和均匀度指数最高。  相似文献   

11.
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.  相似文献   

12.
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 Pfr.  相似文献   

13.
14.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
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。  相似文献   

18.
19.
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  相似文献   

20.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

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