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1.
利用环境DNA宏条形码(environmental DNA metabarcoding;eDNA metabarcoding)检测长江上游珍稀特有鱼类国家级自然保护区重庆段鱼类多样性,探索适用于长江鱼类多样性监测和保护的新方法,为后期长江"十年禁渔"效果评估提供一定的基础资料.研究于2021年3月在保护区重庆段共设置6...  相似文献   

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郭礼和先生(1940年1月─2020年5月),于2000年12月至2020年4月担任《中国细胞生物学学报》(原名:细胞生物学杂志)主编,组建了《学报》第四届、第五届、第六届、第七届编委会。担任主编期间,坚持"提高与普及兼顾"的办刊方针,始终致力于创办一本具有科学性、创新性、实用性的杂志,为细胞生物学科学知识的传播和交流做出了长久持续的努力和贡献。2020年5月1日,于澳门不幸逝世,特此缅怀。郭礼和先生千古!  相似文献   

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鱼类是水域生态系统的重要组成部分, 也是水域生态环境良好的指示类群。为合理评估长江生态环境的现状和变化趋势, 文章提出将土著鱼类物种数和珍稀特有鱼类物种数作为评价指标, 并建立了相关的评价基准和等级划分标准。以2010年和2020年为评价年, 评估了长江干流及代表性重点水域的生态环境质量。结果显示, 当前长江上游干流和下游干流的生态环境质量优于中游; 支流赤水河的生态环境质量良好, 大型湖泊鄱阳湖的生态环境质量中等。从时间上看, 随着长江十年禁渔等一系列保护措施的实施, 长江干流的生态环境质量有不同程度地好转。在此基础上, 提出了进一步改善长江生态环境的对策与建议。  相似文献   

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正自2017年开始策划"地质微生物学专刊"以来,《微生物学报》已成功出版了3期,分别是2018年第4期、2019年第6期与2020年第6期。共发表文章54篇,得到了地质微生物学专家的关注和好评。为系统介绍该领域国内外的最新研究成果,并进一步扩大地质微生物学的影响、促进地质微生物学研究的发展,《微生物学报》专门组织了本期"地质微生物学"专刊。  相似文献   

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长江禁渔     
<正>现在要想保护长江鱼类,需要禁渔10年以上,之后等时机成熟时再采用科学的、现代化的方式捕捞,实现资源的可持续性利用。禁渔对我国水产品供应没有多大影响,因为我国以养殖为主,捕捞为辅,而长江捕捞仅占全国水产品总供应量的千分之一。长江是世界上生物多样性最为丰富的地区之一,生活有白鲟等一百多种特有珍稀的鱼类。此外,长江鱼类还是我国淡水养殖(尤其是四大家鱼)的优良种质来源。四大家鱼历  相似文献   

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封面故事     
正2020年5月22日,习近平总书记勉励内蒙古的同志要大力弘扬"蒙古马精神",这是他近几年来第三次提到"蒙古马精神"。蒙古马是世界上最古老的马品种之一,有超强的耐力,在长途奔袭中,会用一种特殊的"走马"步伐,可以日夜兼程并保持同样的速度。人无精神不立,国无精神不强。随着时代的发展,"蒙古马精神"的内在价值和现实意义日益凸显。早在2014年初,习总书记勉励内蒙古各族干部群众:"马年春节就要到了,  相似文献   

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勘误     
正2020年第3期文章《四川省鸟类名录的修订与更新》第333页右栏"2四川省珍稀濒危鸟类"中的"四川省有分布记录的鸟类中,共有115种被列为国家重点保护野生动物"应为"116种"。本刊向广大读者致歉!  相似文献   

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正2020年10月将迎来中国科学院水生生物研究所建所90周年!为进一步增进广大读者对水生生物学历史、现状和未来发展方向的了解,展示水生生物学最新研究进展,增进水生所与学界同仁的合作与交流,《水生生物学报》拟出版"中国科学院水生生物研究所建所90周年纪念专刊"。专刊现面向历届所友、专家学者及科研人员征稿。征稿范围为水环境保护、渔业可持续发展和微藻生物能源利用等方面的最新研究论文或者综述;请登录学报官网ssswxb.ihb.ac.cn在线投稿,投稿时请备注"所庆专刊";来稿通过同行评议后拟定于44卷第5期正刊(2020年9月)刊发;征稿时间截至2020年3月31日。  相似文献   

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正病毒学报根据中国精品科技期刊遴选指标体系综合评价结果,贵刊入选"第4届中国精品科技期刊",即"中国精品科技期刊顶尖学术论文(F5000)"项目来源期刊。有效期:2017年10月-2020年12月。特此证明。  相似文献   

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正病毒学报根据中国精品科技期刊遴选指标体系综合评价结果,贵刊入选"第4届中国精品科技期刊",即"中国精品科技期刊顶尖学术论文(F5000)"项目来源期刊。有效期:2017年10月-2020年12月。特此证明。  相似文献   

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On the origin of the Hirudinea and the demise of the Oligochaeta   总被引:10,自引:0,他引:10  
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.  相似文献   

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Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor  相似文献   

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