西部地区动物资源现状及持续发展对策

中国西部地区包括陕西、 宁夏、 青海、 新疆、 西藏和内蒙古西部, 其总面积占国土总面积的46.52％,人口占全国总人口的8.33％。共有陆生脊椎动物1273种,占国内2414种的52.73％。其中：两栖类81种,占国内两栖类的28.52％;爬行类119种,占34.69%;鸟类781种,占62.83％;兽类292种,占53.66%。有259种仅分布在西部地区,占西部地区陆栖脊椎动物种数的20.35％,我国大型有蹄类几乎全部集中在西部地区。这里有国家保护的陆栖脊椎动物174种,占全国333种的52.25％; 我国特有鸟、兽54种,占国内特有鸟、兽的60.67%。西部地区丰富的动物资源蕴藏着巨大的经济价值、科学研究价值和生态效益。因环境破坏,乱捕滥猎,近一个世纪以来确知已有普氏野马(Equus przewalskii)、高鼻羚羊(Saiga tatarica)、虎(Panthera tigris)和灰冠鸦雀(Paradoxornis przewalskii)4个物种在西部地区消失。朱(Napponia nippon)已成为极危种类,大熊猫(Ailuropoda melanoleuca)、普氏原羚(Procapra przewalskii)也已接近极危种的界限。一些主要经济动物种群数量逐年下降,马麝(Moschus sifanicus)和林麝(M. berezovskii)分别以年均8.97％和8.44％的速率下降(n=12)。马鹿(Cervus elaphus),白唇鹿(C. albirostris),野牦牛(Bos gruniens)、野驴(Asinus spp.)、藏原羚(Procapra picticaudata)、藏羚（Pantholops hodgsoni)、岩羊(Psendois nayaur)、鹅喉羚(Gazella subgutturosa)等大中型有蹄类遭大肆捕杀。1963年以后得以休养生息正在恢复的动物资源再次遭到破坏。有的种类,如盘羊(Ovis ammon)、野骆驼(Camelus ferus)种群数量分别以年10.06%和10.89％的速率增加(n=16)。为达到持续利用的目的,本文提出六项持续发展对策：加强自然保护区建设、管理;建立各省、自治区自然保护基金;保护栖息环境;迁地保护珍稀濒危物种;人工复壮孤隔种群;提倡人工驯养野生经济动物;人为扩大某些珍稀和经济动物分布区。     

新疆准噶尔盆地生物多样性保育与建立国家荒漠公园的构想

新疆准噶尔盆地拥有世界温带荒漠中最为丰富的野生动植物资源。但由于长期以来过度放牧、开垦、樵采、滥挖、盗猎等人类活动的干扰, 以及目前石油、煤炭等矿产资源的开发, 准噶尔盆地的生物多样性岌岌可危, 迫切需要提出生物多样性保育计划来解决开发与保护之间的矛盾。本文首先从荒漠植被类型、短命植物资源、野生动物资源等几个方面详尽地分析了准噶尔盆地生物多样性的现状, 提出了准噶尔盆地生物多样性保育的重点是: (1)盆地腹地的以梭梭(Haloxylon ammodendron)、白梭梭(H. persicum)等为代表的温带矮半乔木荒漠, 以沙拐枣(Calligonum spp.)、柽柳(Tamarix spp.)等为代表的灌木荒漠, 及以猪毛菜(Salsola arbuscula)、假木贼(Anabasis spp.)为代表的半灌木和矮半灌木荒漠等3种荒漠植被类型; (2) 短命植物资源; (3) 以普氏野马(Equus przewalskii)为代表的野生有蹄类动物; 然后结合准噶尔盆地煤和石油等矿产资源的分布和开发的重点地区, 目前保护区现状以及国外相关的保护经验, 论证了准噶尔盆地生物多样性保育的可行性。基于以上分析, 我们从规划布局以及立法、管理体制、旅游资源管理等方面提出了建立准噶尔国家荒漠公园的构想。     

思茅地区咖啡天牛天敌的多样性调查和控制评价

作者在1994～1997年的调查研究中发现思茅地区拥有丰富的天敌资源。共鉴定出8种主要捕食和寄生于咖啡天牛的天敌,其中蚂蚁类4种：立毛举腹蚁(Crematogaster ferrarii)、黑褐举腹蚁(C.rogenhoferi)、中华小家蚁(Monomorium chinense )和法老家蚁(M.pharaonis );蠼螋2种：蠼螋(Labidura riparia)、锤角螋(Nesogaster sp.);寄生蜂2 种：间斑举腹姬蜂(Pristaulacus intermedius)和茶色茧蜂(Iphiaulax rufus)。饲养和调查结果显示,黑褐举腹蚁、立毛举腹蚁、间斑举腹姬蜂和蠼螋4种捕食或寄生性天敌,自然种群大、控制能力强,有很大的利用前景。建议生产中减少化学农药的施用,以保护天敌的生存环境,发挥天敌的自然控制作用。     

太白山南坡夏秋季鸟类组成

太白山是秦岭山脉的主峰, 生物区系成分复杂。为了研究太白山鸟类区系在过去20年间的变化, 我们于2007年5–7月(夏季)和9–10月(秋季), 根据海拔和典型植被在太白山南坡选定5种生境类型(退耕林、阔叶林、混交林、针叶林和高山灌丛草甸), 并在各种生境中选择样区采用样线法对鸟类组成进行调查。两个季节共观察到鸟类122种, 其中留鸟85种, 夏候鸟31种, 冬候鸟1种, 旅鸟5种。不同的生境类型中优势种和常见种不同, 而且在夏秋两季也有变化。中低海拔退耕林带鸟类物种数最多, 夏季有60种, 优势种为绿背山雀(Parus monticolus)、黄腹山雀(P. venustulus)和冠纹柳莺(Phylloscopus reguloides); 秋季有59种, 优势种为大山雀(Parus major)。中海拔阔叶林带夏季有鸟类40种, 优势种为绿背山雀、黄腹山雀和异色树莺(Cettia flavolivaceus); 秋季37种, 优势种是黄腹山雀、黑冠山雀(Parus rubidiventris)和银脸长尾山雀(Aegithalos fuliginosus)。 中高海拔针阔混交林带夏季有46种, 优势种是黄腰柳莺(Phylloscopus proregulus)、极北柳莺(P. borealis)和黑冠山雀; 秋季有37种, 优势种是黑冠山雀、褐冠山雀(Parus dichrous)和长尾山椒鸟(Pericrocotus ethologus)。高海拔针叶林带夏季有36种, 优势种是黄腰柳莺和黑冠山雀; 秋季有27种, 优势种是血雉(Ithaginis cruentus)和黑冠山雀。高山灌丛草甸带物种最少, 夏秋季都只有7种。各生境中鸟类物种组成的季节周转率随着海拔的升高而下降, 物种丰富度也呈现同样的趋势。太白山南北坡鸟类物种组成有较高的相似性。与20年前相比, 尽管在每种生境类型中优势种和常见种的组成仍相似, 但太白山南北坡的鸟类物种组成有较大的变化。     

生物多样性的进化原理及其保护对策

本文论述了传统进化论学说对生物多样性解释的不足,探讨用生物适化学说解释生物多样性的形成,提出生物多样性产生的表达式： B_d=∫^T_Ｏ［(G_c-m+M)·E_c-(N_t+A_p+H_f)］dt, 并以此说明制订保育它们的原则对策。     

深圳马峦山华南紫萁群落及其物种多样性特征研究

对深圳马峦山地区华南紫萁占优势的植物群落进行研究,结果表明：华南紫萁群落中共有维管植物48科69属82种,种类组成具有明显的南亚热带性质;年龄结构显示群落的主要优势种属于稳定型种群,群落总体处于稳定状态;群落的频度指数规律为A＞B＜C＞D＞E,与RaunKiaer频度定律、海南岛山地雨林优势种群的频度规律等不相符合;华南紫萁种群树高和个体数百分比显示,种群高度0.3~0.7 m植株占比例较大,种群处于旺盛发展期;物种多样性指数为SP＝16.42,SW＝4.56,均匀度指数为E＝0.33,E′＝0.83,群落物种多样性指数和均匀度指数均较高,接近典型南亚热带常绿阔叶林顶极群落类型。本研究揭示了华南紫萁野外生存状态,为该种的保护和利用提供了基础资料。     

保护三峡工程影响的珍稀濒危生物的经济价值评估

运用条件价值评估法, 基于三峡工程对珍稀濒危生物影响的现状和采取的保护措施, 设计了支付卡式调查问卷。通过调查我国31个省(自治区、直辖市)以国有单位为主的职工的支付意愿, 评估了保护三峡工程影响的珍稀濒危生物白鳍豚(Lipotes vexillifer)、白鲟(Psephurus gladius)、达氏鲟(Acipenser dabryanus)、胭脂鱼(Myxocyprinus asiaticus)、中华鲟(Acipenser sinensis)和荷叶铁线蕨(Adiantum reniforme var. sinense)、疏花水柏枝(Myricaria laxiflora)、川明参(Chuanminshen violaceum)的经济价值。回收有效问卷1,036份, 有70.08%的有效问卷反馈者愿意为保护三峡工程影响的这些珍稀濒危生物而支付费用, 平均支付意愿值为127.82元/年。同时采用列联表及卡方独立性检验方法重点分析了总样本各因素对支付意愿值的影响, 结果显示年龄、文化程度、从事职业、个人收入、对三峡工程的了解、对三峡工程的关注、对三峡工程对生物影响的了解等因素与支付意愿值显著相关。最后计算得出保护三峡工程影响的这些珍稀濒危生物的经济价值为82.19×10⁸元/年。以上结果为进一步制定相关保护政策提供了依据。     

湖北沙湖冬季鸟类群落特征

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′、J和C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(S_i)最高,为0.74,农田-水域的相似性指数最低,为0.40;Bray-Curtis指数(C_N)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。     

水稻覆膜处理对稻田杂草多样性的影响

地膜水稻作为一种新的水稻种植方式, 在我国丘陵和山区水稻生产中具有明显的增产效果。地膜稻田中杂草作为重要的有害生物, 有关其群落组成及多样性的报道不多。为了明确地膜稻田杂草的种类、发生密度、优势种及群落多样性, 我们设计了地膜和常规种植两类不同种植模式稻田, 在田间杂草营养生长盛期, 抽样调查了两类稻田中杂草密度、发生程度及生物多样性指数等。结果表明: 地膜稻田和常规稻田杂草种类分别有8科12属12种和10科14属14种。其中常规稻田的马齿苋(Portulaca oleracea)、鸭舌草(Monochoria vaginalis)、拟金茅(Eulaliopsis binata) 和四叶萍(Marsilea quadrifolia) 等在地膜稻田不发生或仅偶有发生, 覆膜稻田中杂草总密度显著降低。异型莎草(Cyperus difformis)和酢浆草(Oxalis corniculata)在两种种植模式田均为优势种, 其相对密度分别为10.29–49.26%和11.91–45.59%, 且地膜稻田的密度均显著低于常规稻田; 而马唐(Digitaria sanguinalis)和水莎草(Juncellus serotinus)仅为地膜稻田的优势种, 其相对密度分别为18.01–30.46%和17.22–23.97%。除个别调查时间外, 两种种植模式稻田杂草群落的Shannon多样性指数和Margalef丰富度指数无显著差异; 而在整个调查期间, 地膜稻田的Pielou均匀度指数均显著高于常规稻田。由此可见, 地膜水稻种植模式不仅对稻田常见杂草和优势种杂草有一定的控制作用, 而且也使整个杂草群落处于一个稳定水平, 避免了一些杂草的暴发, 这对水稻生产过程中的草害控制具有重要的意义。     

蒙古栎群落交错带(ecotone)的研究

通过群落学的样地法对蒙古栎(Quercus mongolica)群落和核桃楸(Juglans mandshurica)群落、蒙古栎群落和长白落叶松(Larix olgensis)群落、蒙古栎群落和杂灌丛群落及其交错带进行了研究,分析了在三个地点的几种群落结构和物种组成方面的差异,计算了各群落的物种丰富度指数(d_Gl)、Simpson 物种多样性指数(D)、Shannon-Weiner物种多样性指数(H′)及Pielou均匀度指数(J)。研究发现在通化和大青沟两个地区群落交错带的物种丰富度及Shannnon多样性指数最高;而在桦甸群落交错带的物种丰富度和物种多样性指数要比核桃楸群落低,比蒙古栎群落高,没有表现出特别强烈的边缘效应。本文也分析了群落乔木层、灌木层和草本层盖度之间的关系。     

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.