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1.
斑背大尾莺鄱阳湖繁殖亚群初报   总被引:3,自引:0,他引:3  
斑背大尾莺(Locustella pryeri)为远东鸟种,主要分布于日本和中国,零星见于俄罗斯极东部、蒙古国东部、朝鲜和韩国,被视为易危鸟种(VU)[1~3]。以往中国鸟类学界多以种名Megalurus pryeri称之,并将该种的中国种群全部视作汉口亚种(sinensis)[4~10]。据记载,斑背大尾莺在我国东北  相似文献   

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2008年1月下旬至2月上旬在中国南方广大地区发生冻雨雪灾害,给在鄱阳湖区越冬的斑背大尾莺(Locustella pryeri)带来不利影响,据3月上旬的调查,原本在江西鄱阳湖南矶湿地国家级自然保护区内广泛分布的斑背大尾莺已变得十分稀少.  相似文献   

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2007年5月20日于辽宁省东港市孤山镇苇田——鸭绿江口湿地国家级自然保护区核心区,在冬季未收割的残留枯草斑块中发现一只白色的雀鸟(封4图片),不鸣叫,飞行姿态及尾部展示与大尾莺(Megalurus)颇为相似。经多次观察发现有雄性大尾莺追随之。23日设网将其捕获,并拍照、称重、度量。最后确定该鸟为雌性斑背大尾莺(Megalurus pryeri sinensis)的白色型(white morph)。该鸟羽色以白色为主,两肋及肛羽沾黄,头顶略现灰,右翼前侧第二枚飞羽前缘距羽端0.2cm有一长0.5cm的黑褐斑。上喙黑褐、下喙肉黄、跗跖肉色等特征与正常大尾莺无异。测量数据如下:…  相似文献   

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2006~2009年,通过点样方方法对斑背大尾莺Megalurus pryeri的巢址进行了研究,获得53个样本,拂子茅Calamagrostis epigejos是营巢生境的主要草本。拂子茅浓密(628根/m2)、芦苇稀疏(20根/1.5 m2)是斑背大尾莺典型的生境,巢高度较高(23 cm)。通过相关分析发现:巢高度和拂子茅总数、绿拂子茅数量显著正相关,但若控制水位、盖度及枯苇数等因素,相关性则不强;巢高度与拂子茅与灯心草等典型草本的高度正相关。进一步分析表明,活拂子茅数量与活苇数量及其他绿草数量负相关。有巢口与无巢口的样方中绿拂子茅数量无差异。对于大尾莺的保护,应该保护芦苇-拂子茅群落,注重芦苇与拂子茅等杂草的平衡。  相似文献   

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为了填补斑背大尾莺食性研究的空白和比较其繁殖期和非繁殖期是否有食性差异,于2011年4月繁殖期,在江西南矶湿地用望远镜观察和录像机拍摄斑背大尾莺亲鸟育雏行为,记录育雏食物的种类和数量;在11月秋季非繁殖期,斑背大尾莺专项环志过程中采集7只意外死亡的个体,进行实验室胃容物解剖分析。两种分析方法分别得出:1)春季取食动物性食物,主要有直翅目蝼蛄科成虫或幼虫、鳞翅目成虫或幼虫、蜻蜓目的成虫,蛛形纲的小型蜘蛛;2)秋季食物由动物性食物(70.24%)和植物性食物(29.76%)组成,动物性食物主要为鞘翅目、直翅目、蜻蜓目、鳞翅目、蜘蛛目等节肢动物,植物性食物为一些植物种子和少量的叶片组织。本研究表明,繁殖期和非繁殖期斑背大尾莺食性有差异,这种差异性是随季节变化生境中的食物组成不同,及育雏期雏鸟需高蛋白营养食物而导致的。  相似文献   

6.
西南地区社鼠的亚种分化兼二新亚种描记   总被引:7,自引:0,他引:7  
系统整理了我国西南及其邻近地区的社鼠标本,发现原指名亚种分布区内的四川雅江八角楼一带的标本,因体背暗黄褐色显著,尾无白色尖端等特征有别于社鼠指名亚种和其他亚种,且其颧板宽与指名亚种Niviventer confucianus confucianus之间的差异系数(C.D.)达1.49,达到亚种水平;而云南德钦的社鼠,因其体背毛黄灰褐色显著,听泡较小,平均约4.9mm等特征与指名亚种及其他亚种差异明  相似文献   

7.
斑尾榛鸡的生态研究   总被引:4,自引:0,他引:4  
1983—1985年在甘肃祁连山东段西营河林区对斑尾榛鸡指名亚种Tetrastes s.sewerzowi的生态和生物学进行了系统观察。本文报道斑尾榛鸡的栖息环境、活动规律、食性,繁殖习性及天敌等。  相似文献   

8.
斑背大尾莺繁殖期鸣声行为分析   总被引:3,自引:0,他引:3  
Qu WH  Li F  Sha JB  Zhang YM 《动物学研究》2011,32(2):141-149
2009年5-7月,在辽宁双台河口保护区录制了20只繁殖期斑背大尾莺雄性个体的鸣声.根据行为特征,该鸟鸣声定义为3种鸣声类型:求偶炫耀鸣唱、报警声和联络声.利用Wavesurfer软件对20只斑背大尾莺雄性个体543个鸣声的句子持续时间、句子音节个数、音节持续时间、音节间隔时间等4个参数进行分析测量,发现求偶炫耀鸣唱由节奏逐渐加快的前部句子和音节组成复杂的主体部两个句子组成; 报警声和联络声的句子均由单音节组成.音节类型总数为38种,其中包括前部句子的音节类型6种.采用单因素方差分析(one-way ANOVA)对求偶炫耀鸣唱的4个参数进行差异性检验发现,不同个体的各个参数均呈极显著差异(P<0.01).  相似文献   

9.
2016年9和10月,在西藏自治区林芝及日喀则开展鸟类多样性调查期间新记录到8种鸟类,包括白胸翡翠指名亚种(Halcyon smyrnensis smyrnensis)、黑冠山雀指名亚种(Periparus rubidiventris rubidiventris)和栗腹?指名亚种(Sitta cinnamoventris cinnamoventris)、斑尾鹃鸠(Macropygia unchall)、红喉姬鹟(Ficedula albicilla)、黄胸柳莺(Phylloscopus cantator)、棕脸鹟莺(Abroscopus albogularis)以及田鹨(Anthus richardi)。  相似文献   

10.
牛背鹭(Bubulcus ibis)作为入侵物种由非洲向美洲的扩散得到了广泛关注,然而牛背鹭与其竞争物种之间的巢空间生态位分化动态尚不明确。为了解牛背鹭与其他混群繁殖鹭类的巢空间生态位分化动态,2012、2016和2021年春夏季,对中国云南大理古城繁殖鹭类的群落结构和巢空间分布进行了调查。结果表明,2012和2016年中国云南大理古城繁殖鹭类群落的组成物种均为牛背鹭、夜鹭(Nycticorax nycticorax)和白鹭(Egretta garzetta),其中夜鹭为优势鸟种;2021年繁殖群落增加了中白鹭(Ardea intermedia),且牛背鹭变为优势鸟种。从2016年到2021年群落巢密度增加,其中牛背鹭的巢密度明显增加,夜鹭和白鹭巢密度均减少。对比2016和2021年牛背鹭、夜鹭和白鹭3种鹭的巢空间生态位宽度数值的变化,发现牛背鹭利用的巢空间生态位更泛化,而夜鹭和白鹭更特化;巢空间生态位重叠值变化表明,2021年牛背鹭对夜鹭、白鹭的巢址竞争比2016年的更激烈,而且2021年牛背鹭与夜鹭之间的巢址竞争比牛背鹭与白鹭之间的更激烈。研究表明,在2012、2016和2021年,在大理古城鹭类繁殖地中,牛背鹭在与比自身个体大的夜鹭的竞争中胜出,群落优势鸟种由夜鹭变为牛背鹭,繁殖鹭类的群落结构和生态位分化均发生了明显变化。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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