卫星跟踪技术在鸟类迁徙研究中的应用及展望

综述了利用人造卫星跟踪技术进行鸟类迁徙研究的现状和利用卫星遥感技术对鸟类栖息地环境进行分析研究的现状。指出了这两项技术目前存在的问题,提出将这两项技术结合起来将有助于弄清候鸟迁徙定向、迁徙路径选择的机理,揭开候鸟迁徙策略之谜,有助于从景观生态学和保护生物学的角度研究并预测环境变化给候鸟带来的影响。     

鸟类迁徙的研究方法和研究进展

鸟类的迁徙长期以来一直是人类最感兴趣的自然现象之一。随着科技的不断发展,各种先进的仪器设备和研究方法被应用到鸟类迁徙的研究中,为深入了解鸟类的迁徙活动起到了重要作用。介绍了野外观察、雷达监测、环志、卫星跟踪、稳定同位素和室内控制实验等鸟类迁徙的主要研究方法、并介绍了近年来在鸟类的迁徙停歇地和迁徙路线以及鸟类迁徙的能量代谢方面的研究成果,供广大读者参考和借鉴。     

中国侯鸟环志的研究

环志是研究鸟类迁徙最简单有效的科学方法。中国从１９８２年开始建立全国鸟类环志中心以来,在林业部的领导下至１９９０年先后建立了候鸟环志站、点６０处,共计环志了候鸟１８６种６２７５５只,同期回收到国内外环志鸟４１３只。回收环志鸟提供了东亚地区候鸟迁徙的宝贵信息,证实了：１．候鸟迁徙可自喜马拉雅山脉飞越;２．中国候鸟迁徙路线和推论是正确的;３．中国东北繁殖的白枕鹤飞往日本九洲南部越冬,丹顶鹤等迁往东部沿海、长江中下游几处湿地越冬,与来自俄罗斯西伯利亚的部分鹤在相同地区越冬;４．某些鸟种迁徙路线在与日本同种候鸟迁徙路线比较后,表明在西太平洋地区,通过中国和日本存在着两条平行的自南向北迁徙的路线。其他信息也指出了更多的情况,同时也表明中国环志研究在西太平洋迁徙候鸟研究中处于关键性的地位。     

中国候鸟环志的研究

环志是研究鸟类迁徙最简单有效的科学方法。中国从1982年开始建立全国鸟类环志中心以来,在林业部的领导下至 1990年先后建立了候鸟环志站、点 60处,共计环志了候鸟 186种 62 755只,同期回收 到国内外环志鸟413只。回收环志鸟提供了东亚地区候鸟迁徙的宝贵信息,证实了：1．候鸟迁徙可自喜马拉雅山脉飞越;2．中国候鸟迁徙路线和推论是正确的;3．中国东北繁殖的白枕鹤飞往日本九洲南部越冬,丹顶鹤等迁往东部沿海、长江中下游几处湿地越冬,与来自俄罗斯西伯利亚的部分鹤在相同地区越冬;4.某些鸟种迁徙路线在与日本同种候鸟迁徙路线比较后,表明在西太平洋地区,通过中国和日本存在着两条平行的自南向北迁徙的路线。其他信息也指出了更多的情况,同时也表明中国环志研究在西太平洋迁徙候鸟研究中处于关键性的地位。     

我校候鸟的物候观测

初中动物学教材指出:“关于鸟类的迁徙至今还有许多有趣的问题没有研究清楚。例如:形成鸟类迁徙本能的历史原因是什么?鸟类迁徙的生理原因是什么?今后需要对这些问题做更进一步地观察、实验和分析研究。”笔者1987年在学生中成立以研究候鸟迁徙为目的的物候观测兴趣小组,开展了活动。我们的做法是:     

全球气候变暖对武汉作为鸟类迁徙"中转站"地位的威胁

武汉市位于中国腹地,长江和汉水的交汇处,这里一直是南北候鸟迁徙的"中转站"之一,更是重要的候鸟越冬地和停歇地.由于地处南北过渡性气候,适合南、北候鸟常年生活,再加上"百湖之城"良好水资源条件和湿地环境更为鸟类的取食及营巢奠定了基础.正是因为这些气候及地理条件,所以有很多候鸟在此安家.然而,随着全球气温出现了整体上升的现象,这样的气候条件对鸟类的迁徙、繁殖是十分不利的.本文结合作者及其他学者对武汉鸟类调查的结果与近年武汉市气候状况的比对分析,发现武汉作为鸟类迁徙"中转站"的生态学地位发生了巨大变化,并讨论了全球气候变暖对武汉作为南北鸟类中转站生态地位的威胁状况,阐述了对全球环境保护的建议.     

哀牢山北段大中山候鸟聚集地秋季夜间迁徙鸟类多样性

环志是研究迁徙鸟类的重要途径。云南省哀牢山北段大中山是鸟类迁徙的重要通道,但缺乏具体的研究数据。1997年、2010年和2011年秋季夜间迁徙鸟类环志研究的结果表明,哀牢山北段大中山捕获到的夜间鸟类有108种2330只,分属10目24科。其中,以雀形目鸟类为主,占总捕获数量的78.3%,捕获优势种为树鹨(占捕获数量的16.95%)、红喉姬鹟(13.39%)、红尾伯劳(9.83%)、红喉歌鸲(8.71%)和栗鹀(4.80%);水禽占捕获鸟类总种数的16.7%,与云南其他地点的研究结果相似。由于水禽是传播禽流感的主要载体,候鸟聚集地存在传播禽流感的风险,春季也有候鸟翻越哀牢山,因此有必要开展春季鸟类环志工作。     

近10年秦皇岛两种鸟类春季迁徙 时间变化的差异性

气候变化对鸟类迁徙时间的影响是目前生态学研究的热点问题。本文利用鸟类环志的方法分析了2010至2019年河北秦皇岛两种鸟类春季迁徙时间变化趋势及其差异性,并进一步探讨了差异性的原因。选择环志数量较多的食虫鸟黄眉柳莺(Phylloscopus inornatus)和食谷鸟灰头鹀(Emberiza spodocephala)作为研究对象,分析了10年间两种鸟类春季迁徙到达时间、高峰期、离开时间和停歇天数的变化及其相关性。结果表明,10年间黄眉柳莺和灰头鹀春季迁徙到达时间、高峰期和离开时间都出现了提前现象。黄眉柳莺和灰头鹀在秦皇岛停歇天数都呈现缩短的趋势,黄眉柳莺到达时间与离开时间存在显著的正相关。两种候鸟春季迁徙时间出现这种变化的原因是由于秦皇岛环境温度呈现逐渐升高的趋势,促使各种植被群落和昆虫提前进入生长繁殖阶段,为春季提前迁徙而来的候鸟提供丰富的食物资源。黄眉柳莺春季迁徙期在秦皇岛采取“早到早走”的策略,提早到达繁殖地可以增加其繁殖成功率,有助于提高鸟类种群的生存率。     

青岛市1999年秋季鸟类迁徙报告

青岛市地处山东半岛西南端 ,位于北纬 3 5°3 5′～3 7°0 9′、东经 1 1 9°3 1′～ 1 2 1°。由于濒临黄海 ,受海洋季风的影响 ,雨量充沛 ,温度适中 ,冬无严寒 ,夏无酷暑 ,年平均气温 1 2 2℃ ,最低月均温 -1 2℃ ,最高月均温 2 5℃ ,植物资源丰富 ,昆虫及海洋生物多 ,是东部沿海候鸟迁徙的主要停歇地。青岛鸟类保护环志站是中国大陆最早建立开展鸟类环志研究的站点之一。迄今已环志鸟类 5 8万只。在 1 3处环志点开展了鸟类迁徙环志研究 ,积累了一些资料。目前已查明境内有旅鸟 2 52种、冬候鸟 3 4种、夏候鸟 4 9种。1　环志点及工作方…     

稳定同位素分析在鸟类生态学中的应用

稳定同位素作为一种自然标记物是研究鸟类生态学的重要工具之一,与传统研究方法相比其呈现的信息更为真实全面,是一种日趋成熟的鸟类生态学研究方法。近几年该方法在鸟类迁徙生态学、取食生态学等方面取得较大成就,展现出传统研究方法无可比拟的优越性。但目前该方法在我国鸟类生态学上的应用较少,基于此,从迁徙、取食等方面分别阐述稳定同位素在鸟类生态学上的应用,以促进我国鸟类生态学的快速发展和推动稳定同位素生态学与其它学科的交叉融合。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.