贵州省金沙县3种鹎科鸟类的夏季食性

报告了黄臀鹎、白头鹎、绿鹦嘴鹎的夏季食性，研究表明，这３种鸟在该季节均为杂食性鸟类，其中绿鹦嘴鹎以植物果实为主，黄臀鹎以昆虫为主。     

食果鸟类对秋枫果实的取食和传播研究

食果鸟类对植物果实的取食和传播在植物种群的更新和扩散中具有重要意义。2020年11月至2021年1月,采用焦点动物扫描法并借助Safari 10×26变焦双筒望远镜,观察鸟类对校园内秋枫Bischofia javanica果实的取食行为,详细记录鸟类种类、取食基质、访问频次、取食时间、取食数量和取食方式等信息,探讨秋枫母树的特征(结实量、郁闭度和高度)和鸟类的体型特征(喙长、体长和体质量)对鸟类取食行为的影响。结果表明：研究期间共观察到5种鸟类取食秋枫植物的果实,其中白头鹎Pycnonotus sinensis、红耳鹎Pycnonotus jocosus、白喉红臀鹎Pycnonotus aurigaster和黄臀鹎Pycnonotus xanthorrhous等4种鸟类以整吞的方式取食秋枫种子,属于种子潜在传播者。不同种鸟类对秋枫果实的平均访问只数、平均取食时间和平均取食量存在极显著差异。相关性分析表明,秋枫结实量与访问母树的鸟类数量、种数、Shannon-Wiener指数和Simpson指数呈正相关,母树郁闭度和高度均与访问母树的鸟类数量呈正相关;鸟类的体长、体质量和喙长与平均取食量...     

井冈山国家级自然保护区鸟类资源研究

2005～2007年对井冈山国家级自然保护区鸟类进行调查,发现当地两种鸟类新记录:黄臀鹎(Pycnonotus xanthorrhous)和锡嘴雀(Coccothraustes coccothraustes).保护区共有鸟类162种,隶属16目50科,占江西省鸟类的45.25%,其中黄腹角雉(Tragopan caboti)、灰胸竹鸡(Bambusicola thoracica)、白颈长尾雉 (Syrmaticua ellioti)、画眉(Garrulax canorus)、领雀嘴鹎(Spizixos semitorques)和黄腹山雀(Parus venustulus)是中国特有种.黄腹角雉、白颈长尾雉、鸳鸯(Aix galericulata)、褐翅鸦鹃(Centropus sinensis)和小鸦鹃(Centropus bengalensis)被列入<中国濒危动物红皮书>.保护区有19种鸟类列人CITES<濒危野生动植物种国际贸易公约>附录,有国家重点保护动物21种,江西省重点保护鸟类40种.这些表明井冈山鸟类资源丰富,但近年来人类活动影响了当地鸟类资源.     

最美丽的照片

正图为红耳鹎。红耳鹎,善鸣叫,主要吃植物性食物。如今,红耳鹎种群数量已明显下降,应受到保护。一一、飞来横祸陈"我快坚持不住了!""救超群救我们!"……我和哥哥姐姐蜷在巢里,拼尽全力呼救。我是一只刚孵出的红耳鹎,有勤劳的爸爸妈妈和三个可爱的哥哥姐姐,原先住在公园里路边的一棵松树上。未来有一天,我会长得     

白眶鹅莺等12种上海市鸟类新记录

2012年9月至2015年4月,有9种鸟类在上海市内首次被发现,分别是:白眶鹟莺Seicercus affinis、棕脸鹟莺Abroscopus albogularis、冠纹柳莺Phylloscopus claudiae、绿背姬鹟Ficedula elisae、褐胸鹟Muscicapa muttui、宝兴歌鸫Turdus mupinensis、漠Oenanthe deserti、灰翅鸥Larus glaucescens和蛇雕Spilornis cheela;另有3种此前已被记录到但未记入上海鸟类名录的鸟类再次被发现,分别是:赤嘴潜鸭Netta rufina、灰树鹊Dendrocitta formosae和黄臀鹎Pycnonotus xanthorrhous.这12种鸟类均被确定为上海市鸟类新记录,目前上海市有记录的鸟类共计20目70科457种.     

天童20 hm~2常绿阔叶林样地优势鸟类时空多维度生态位分析

2011年10月2012年10月,对浙江天童山20 hm~2样地内鸟类利用资源情况进行观察.共观察记录鸟类43种,数量4 823只,并对样地内6种优势鸟类(黑[短脚]鹎Hypsipetes leucocepalus、白头鹎Pycnonotus sinensis、栗背[短脚]鹎Hypsipetes castanonotus、红头长尾山雀Aegithalos concinnus、大山雀Parus major和灰眶雀鹛Alcippe morrisonia)在垂直维度、水平维度、DBH维度和栖树维度上采用Hurlbert公式,得到各优势种生态位宽度值;采用Schoener公式对优势鸟类不同维度的生态位重叠进行分析并对生态位时空变化进行探讨.结果表明:森林生态系统中优势鸟类在不同维度上存在生态位分离;优势种不同时空生态位呈动态变化,最终在多维度水平上趋于稳定.由此,确认了占据优势种群地位的鸟类在不同生态位维度上的分离和生态位时空动态变化是群落结构处于稳定状态的主要原因.     

海南岛鸟类新记录种—红耳鹎

2010年11月-2011年1月,先后在海口多个地点观察到红耳鹎(Pycnonotus jocosus)的群体,确认为海南岛的鸟类新记录种.     

上海冬季的鸟类“餐桌”

上海因其特殊的地理位置而成为众多候鸟迁徙途中重要的停歇地和补给站.在寒冷的冬季,黄雀、白头鹎、灰喜鹊、小太平鸟、黑尾蜡嘴雀、八哥、北红尾鸲和栗耳短脚鹎等众多鸟类在这里找到了分享美食的“餐桌”. 据《上海常见鸟类图鉴》记载,上海地区冬季有留乌44种、冬候鸟133种、旅鸟197种.由于上海位于长江入海口,属北亚热带季风气候,冬季气温相对较低,鸟类的食物资源减少,一些枝头尚挂有果实的灌木和乔木便成了它们的“餐桌”.     

红耳鹎生态学的初步研究

本研究于1984——1991年间在广西的贺县,南宁、隆林等地进行。作者对红耳鹎在金钟山北坡四种林型中的分布数量作了调查,夏季在桂西金种山北坡的四种林型中,红耳鹎的分布数量以河谷农田稀树灌丛林最高,密度为1.13％ha。繁殖期为2～8月,雌鸟筑巢,窝卵数在2～4枚,以3枚居多,卵均重2.8(2.4～3.4)g平均大小为:15.7(15.2—16.0)mm×21.9(20.6～24.7)mm。仅雌鸟孵卵,孵化期约10～11天。卵孵化率为86.9％,巢中育雏期10～12天,双亲共同育雏,对其食性作了分析。植物性食物占64.8％,动物性食物占27.8％。     

两种野生鸟类染色体组型初报

本文以骨髓或羽髓细胞为材料,分析了两种鸟的染色体组型,其结果锡嘴雀2n=78±,AN=88±;白头鹎2n=80±,AN=88±。两个种均具有典型的鸟类两型性核型,即核型中有7对大型染色体和32—33对微小染色体。白头鹎的核型尚属首次报道。与已经报道的本属另一物种——黑喉红臀鹎的核型相比较,讨论了它们的演化关系。白头鹎可能属较原始的物种。     

A long-tailed,seed-eating bird from the Early Cretaceous of China

The lacustrine deposits of the Yixian and Jiufotang Formations in the Early Cretaceous Jehol Group in the western Liaoning area of northeast China are well known for preserving feathered dinosaurs, primitive birds and mammals. Here we report a large basal bird, Jeholornis prima gen. et sp. nov., from the Jiufotang Formation. This bird is distinctively different from other known birds of the Early Cretaceous period in retaining a long skeletal tail with unexpected elongated prezygopophyses and chevrons, resembling that of dromaeosaurids, providing a further link between birds and non-avian theropods. Despite its basal position in early avian evolution, the advanced features of the pectoral girdle and the carpal trochlea of the carpometacarpus of Jeholornis indicate the capability of powerful flight. The dozens of beautifully preserved ovules of unknown plant taxa in the stomach represents direct evidence for seed-eating adaptation in birds of the Mesozoic era.     

Erosion-corrosion and its mitigation on the internal surface of the expansion segment of N80 steel tube

We investigated erosion-corrosion(E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization techniques.The results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various locations.Consequently, it can be expected that localized corrosion often occurs in such segments.The E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction rate.However, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion segment.This means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.     

Erosion-corrosion and its mitigation on the internal surface of the expansion segment of N80 steel tube

We investigated erosion-corrosion(E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization techniques.The results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various locations.Consequently, it can be expected that localized corrosion often occurs in such segments.The E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction rate.However, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion segment.This means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.     

古籍《诗经》中的鸟类古汉名考证

《诗经》中有许多鸟类古名与现代鸟名大都不一致,为了承救古文化,沟通古今,沟通中外,使读者更好地理解诗文,笔者应用现代动物学与训诂学相结合的方法考证了《诗经》中记载的鸟类名称,把它们归属于现代鸟纲10个目、22个科,共42种.     

土地利用与覆被变化对鸟类群落组成影响研究 ——以杭州湾河口为例

以人口分布相对集中的区域杭州湾河口为例,通过遥感技术、野外调查和典型对应分析(CCA)排序分析的方法,对该区域的鸟类群落组成和结构进行研究.结果表明:1)土地利用与土地覆盖(LULC)影响鸟类群落的组成,鸟类的种类分别为农田31种、滩涂湿地30种、工业园区18种;鸟类的数量组成分别为滩涂湿地588只次、农田356只次、...     

中国猛禽类线粒体DNA遗传多态性研究进展

鸟类线粒体ＤＮＡ的研究在种群生物学和进化生物学研究方面越来越显示出重要的作用,特别是在遗传多态性和基因流研究方面更具特殊意义。简要回顾了鸟类线粒体ＤＮＡ的研究历史,并分析了中国猛离线粒体ＤＮＡ遗传多态性的研究现状及进展,要点：１．猛禽类线粒体基因组大小存在遗传多态性,２：猛禽类线粒体ＤＮＡ的进化速率与哺乳类相同,３;种间或种内存在丰富的遗传变异;４．不同地理种群存在ｍｔＤＮＡ克隆群的连续性。     

Spectroscopic mapping of voltage sensor movement in the Shaker potassium channel

Voltage-gated ion channels underlie the generation of action potentials and trigger neurosecretion and muscle contraction. These channels consist of an inner pore-forming domain, which contains the ion permeation pathway and elements of its gates, together with four voltage-sensing domains, which regulate the gates. To understand the mechanism of voltage sensing it is necessary to define the structure and motion of the S4 segment, the portion of each voltage-sensing domain that moves charged residues across the membrane in response to voltage change. We have addressed this problem by using fluorescence resonance energy transfer as a spectroscopic ruler to determine distances between S4s in the Shaker K+ channel in different gating states. Here we provide evidence consistent with S4 being a tilted helix that twists during activation. We propose that helical twist contributes to the movement of charged side chains across the membrane electric field and that it is involved in coupling voltage sensing to gating.     

论雍正帝对珐琅彩花鸟瓷画艺术的影响

花鸟画是雍正珐琅彩瓷装饰的主要题材,雍正帝对于珐琅彩花鸟瓷画艺术的兴盛与发展具有关键影响.在雍正帝的直接监督参与下,珐琅彩花鸟瓷画在工艺上取得重大进步,达到兴盛发展的程度,在艺术上也显现出与前不同的新风格.     

软硬地层下双顶管掘进参数对管片及地层的影响性研究

软硬地层中双顶管掘进参数不当所导致的周围土体变形、姿态偏离、刀盘磨损等问题在实际工程中屡有发生。以南宁平花河顶管为工程背景,通过数值模拟研究软硬地层中不同掘进参数组合对周围地表沉降及管片应力的影响。得到结论如下：开挖面掘进压力对地表变形的影响呈现出非线性特征,地表沉降及其减小的速率随着掘进压力增大而减小;注浆压力与横向地表沉降之间呈现出线性递减的趋势,影响区域约为双隧道中心2倍隧道直径范围内;管片最大Mise应力与盾尾注浆压力、千斤顶推力均呈现线性递增的关系,当注浆压力、管片千斤顶推力分别增加10 kPa,每环管片的最大Mises应力相应分别增加64 kPa、17 kPa;开挖面掘进压力增大时,管片应力呈向着非线性递增的趋势,管片应力变化也相应减小,掘进压力从0kPa变化至20 kPa时的管片应力变化率为40~60 kPa的1/4~1/3     

内蒙古包头地区候鸟迁徙状况的研究

包头地区具有大面积的黄灌水系，山地、草原、生态环境复杂，故为众多候鸟繁殖和旅居的适宜地区。对研究中国西部候鸟迁徙具有重要价值．从１９９０年至１９９７年对候鸟迁徙状况的初步观察研究．