江西水域枯水期长江江豚种群数量和分布特征

研究于2021年11—12月,设置12条考察路线,采用同步目视考察法,对包含长江干流江西段、鄱阳湖和赣江下游的江西水域长江江豚数量和分布开展了考察,结合历史资料,探讨了该水域长江江豚种群数量和分布规律及江湖迁徙关系。结果显示, 11月考察观测到长江江豚217群次、454头次, 12月考察观测到长江江豚236群次、569头次,受水位和天气等环境条件影响,两次考查观察到的长江江豚数量差异显著(t=–2.23, P<0.05)。11月和12月江豚分布规律基本一致:长江江西段,江豚主要分布在湖口石钟山-彭泽三号洲水域;鄱阳湖适宜水深范围水域都有长江江豚分布,其中吴城望湖亭-渚溪河口、都昌船厂-黄金咀-三山-瓢山水域是江豚高密度分布区;赣江下游,长江江豚分布在扬子洲渔业村附近水域。两次考察目击率分别为1.00和1.08次/km,均高于往年调查结果,由此推测,鄱阳湖长江江豚种群数量可能有所增长。鄱阳湖通江水道蛤蟆石-石钟山水域,两次考察分别仅发现3头和2头长江江豚,推测调查期间长江江豚在长江干流和鄱阳湖之间的迁移行为较少,未来需进一步管控江湖迁移水域的人类活动,促进江湖迁移。吴城望湖亭-渚溪...     

长江江豚一例腹壁肌间巨型囊肿的组织学分析

正随着白暨豚(Lipotes vexillifer)的"功能性灭绝",江豚(Neophocaena asiaeorientalis)已成为长江目前唯一能见的鲸类物种~[1]。江豚曾被划分为3个亚种,即指名亚种(N.phoconoides phoconoides)、长江亚种(N.phoconoides asiaeo-     

一只长江江豚妊娠期昼间行为及其时间分配

长江江豚(Neophocaena phocaenoides asiaeorientalis Pilleri and Gihr,1972)属于哺乳纲(Mammalia)、鲸目(Cetacea),是仅分布于长江中下游及其附属湖泊中的惟一且相对独立的一个江豚淡水亚种(高安利和周开亚,1995),也是中国水域中三个江豚种群中最为濒危的一个亚种,<中国濒危动物红皮书·兽类>也将其列为濒危级(汪松,1998).     

长岛海域东亚江豚种群密度和分布的初步研究

长岛海域是黄渤海东亚江豚(Neophocaena asiaeorientalis sunameri)的热点分布区域之一。为了掌握长岛海域东亚江豚的种群密度与分布特征，2019年10月至2021年10月采用截线抽样法进行了5次东亚江豚目视考察。5次考察总航程2 421 km，共发现东亚江豚614次，1 156头次。相同月份调查种群遇见率无显著性差异(P> 0.05)，不同月份种群遇见率差异极显著(P <0.01)，提示东亚江豚种群在该水域可能存在季节性迁移。按照考察月份对数据进行合并处理，长岛海域5月和10月东亚江豚平均种群密度为(0.56±0.11)头/km²(0.46～0.68头/km²)和(3.63±0.25)头/km²(3.38～3.88头/km²)，平均种群数量为(20 209±202)头和(2 971±681)头，这在目前已知所有东亚江豚分布区中是最高的。尽管不同季节种群数量差异显著，但东亚江豚种群在长岛海域的空间分布特征相似，砣矶岛-大钦岛西北侧和东南侧均为高密度分布区，因此...     

长江安庆段航道整治对长江江豚数量和分布的时空影响

栖息地丧失和破碎化是威胁长江江豚(Neophocaena asiaeorientalis)种群长期发展的主要因素之一。航道整治工程是导致江豚栖息地丧失和破碎化的一个主要原因,研究工程施工和运行对江豚数量和分布的影响可为江豚栖息地管护提供有益信息。通过对湖口-吉阳矶水域江豚数量和分布的持续调查,分析了安庆段航道整治工程施工和运行对江豚的影响。12次目视调查共在研究水域发现江豚258群次613头次,工程施工前、施工期和初步运行期单次考察分别平均观察到江豚(67.0±24.3)头次、(35.6±22.2)头次和(50.0±2.8)头次。在主要施工区共发现江豚79群次185头次,施工前、施工期和初步运行期单次考察分别平均观察到江豚(18.60±12.03)头次、(10.4±7.3)头次和(20.0±4.2)头次。工程不同时期主要施工区江豚的数量及占比在统计学上没有显著差异。主要施工区S2和S3工程段施工期江豚平均分布密度((0.18±0.17)头/km、(0.04±0.08)头/km)较施工前((0.62±0.16)头/km、(0.40±0.29)头/km)显著下降,S5和S6工程段施工期平均...     

长江口两种江豚亚种体脂内多氯联苯同分异构体含量的比较分析

为了弄清长江口江豚(Neophocaena asiaeorientalis)体脂内多氯联苯(PCBs)的累积情况,采用气相色谱质谱联用仪(GC-MS)对5头东亚亚种(N.asiaeorientalis sunameri)和3头长江亚种(N.asiaeorientalis asiaeorientalis)的10种多氯联苯同族物(PCBs)含量进行了测定。研究发现,长江口江豚体脂中多氯联苯(PCBs)的平均含量为3.38μg/g(湿重),其中,长江亚种的多氯联苯(PCBs)含量(3.40~12.67μg/g)要显著高于东亚亚种(0.33~2.21μg/g)。在10种多氯联苯(PCBs)中,一氯、二氯和三氯联苯在所有个体中均未测出(小于0.005μg/g),但四氯、五氯、六氯和七氯联苯在所有个体中都被测出,其中,六氯联苯的平均含量高达1.48μg/g,占总含量的43.79%。从含量的组成看,六氯联苯和七氯联苯均构成了长江口江豚体脂内多氯联苯(PCBs)的主要成分,但相比东亚亚种,长江亚种的四氯联苯和五氯联苯也占较高的比例。研究表明,低氯代组分的多氯联苯(PCBs)可以随水流的稀释和生物转化而逐渐降解,但高氯代组分的多氯联苯(PCBs)则不易降解,并且随江豚年龄的增长而快速积累,产生更持久的毒性效应。     

半自然水域中长江江豚活动区域及其季节性变化

长江江豚 (Neophocaena phocaenoides asiaeorientalis)是江豚独立的淡水种群,近年来其种群数量呈急剧下降趋势1。       

鄱阳湖长江江豚的微卫星遗传多样性及发展预测

为了科学评估鄱阳湖长江江豚(Neophocaena asiaeorientalis asiaeorientalis)的遗传多样性并预测其发展趋势,研究基于124头活体长江江豚的血液样本及42头搁浅死亡长江江豚的组织样本,利用微卫星遗传标记对该种群的遗传多样性进行了评估,并利用BottleSim软件对该种群遗传多样性的发展趋势进行了模拟预测。研究结果显示,鄱阳湖长江江豚种群10个微卫星位点的平均等位基因数(N_a)为5.80、平均观察杂合度(H_o)为0.653、期望杂合度(H_e)为0.664,表现出中等程度的核DNA遗传多样性;在剔除死亡个体后,平均等位基因数下降至5.50,并且死亡个体在3个微卫星位点上具有3个稀有等位基因,表明非正常死亡将导致鄱阳湖种群遗传多样性下降。此外,模拟结果表明,如果保持当前有效种群(N_e=62)和雌雄性比(0.87:1),鄱阳湖长江江豚种群的遗传多样性将快速下降;而要实现100年内保存90%以上遗传多样性的目标,则其有效种群至少需要200头或者实际种群数量超过1000头。研...     

渤海江豚种群现状初探

渤海是黄渤海江豚种群的重要分布区,但是有关该区域江豚的种群数量的资料极其匮乏。2015年至2016年,采用截线抽样法在渤海水域开展了6个航次的目视调查,收集了渤海江豚的分布数据,首次评估了区域内的江豚种群数量,为制定有效的渤海江豚种群生态保护策略提供了基础资料。调查结果显示,在2015年8月、2016年5~7月、9月和11月进行的6个调查航次共计8972 km的有效航程中,发现江豚87次、136头次。江豚在渤海各海湾和中部水域都可观察到;14:00-18:00时段、离岸15~35km范围内较易观察到江豚;黄河口外、秦皇岛东北侧老龙口和莱州外沿岸河口水域,江豚出现频次较多。各季节中,以5月在黄河口外20~40km范围内发现江豚的频次和数量最多。采用Distance 7.0软件估算渤海江豚种群数量,其中探测概率分别取值0.399、0.85和1时,渤海江豚种群数量估算值分别为7883头（CV=0.21）、3701头（CV=0.21）和3124头（CV=0.21）,对应的种群密度分别为1.441头/km2、0.066头/km²和0.056头/km²,均低于已报道的南黄海和日本海江豚种群相应值。受海上天气、调查条件和经验所限,本文估值可能存在偏差,但限于渤海江豚历史资料缺乏的现状,本文的结果对于认识渤海江豚的种群状况仍具有重要参考意义。     

鄱阳湖原地保护

目前长江干流和洞庭湖中的长江江豚处境危急,特别是洞庭湖中的种群可能最先走向野外灭绝.与这两处水域不同,根据2005～2012年的连续监测,鄱阳湖长江江豚的种群数量虽然在不同年度及季度之间有一些变动,但总体上维持在一个相对稳定的状态,约为450头.这是十分有趣的现象,为何独独鄱阳湖长江江豚的种群数量能够在过去8年维持相对稳定呢？其实,这还是与鄱阳湖保持相对较好的水域生态环境相关.我们认为,鄱阳湖长江江豚种群数量的稳定与鄱阳湖“洪水一片,枯水一线”的自然生态水文节律、统一集中的渔政管理机制及相对干流和洞庭湖区较低的人类活动强度直接相关.     

六种藓类植物茎的比较解剖学研究

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.     

Photoregulation of seed germination of wild-type and of an aurea-mutant of tomato

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 P_fr.     

真菌类遗传学分析的知识结构教学

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.     

Interconnection of parameters of regulation system of lipid peroxidation and of morphophysiological parameters of mouse liver

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.     

Time of detection of recessive genes: effects of system of mating and number of examined individuals

Summary Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, Siete Cerros 66 and Penjamo 62, as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of Penjamo 62 in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.     

Cause of Senescence of Nine Sorts of Flowers

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.     

Physiological characteristics of various species of strains of carboxydobacteria

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