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Three species of Arietellidae are described from the south‐west Pacific: a new species of Paraugaptilus, a species which can not be separated from P. buchani, and Arietellus aculeatus. The identity of A. aculeatus is clarified by comparison of type material and material from the U.S. National Museum of Natural History, and an unidentified Atlantic species of Arietellus, evident from the comparison, is described.  相似文献   
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皱纹盘鲍是我国重要的增养殖贝类,近年来养殖产量增长迅速,但现有养殖群体仍存在抗逆性不足、底播增养殖低效等问题。个体身份的标记技术对于皱纹盘鲍人工选育中谱系记录,以及对于底播增殖效果的精准评估等均具有重要作用。采用金属挂片和塑料黏贴标签两种标记方法,比较了标记后皱纹盘鲍生理、生长存活、标记脱落率及被敌害捕食死亡等方面的差异。研究结果表明,与塑料黏贴标签标记和无标记对照相比,金属挂片标记对皱纹盘鲍标记早期生理包括出现黏液时间、心率变化等产生显著影响,对小规格皱纹盘鲍(壳长<3 cm)造成生长下降、死亡率高等影响,而对大规格皱纹盘鲍(壳长>3 cm)标记生成60 d后长时期的生长、存活以及逃避敌害均无显著影响;塑料黏贴标签标记方法与无标记对照组相比,均未对皱纹盘鲍造成显著影响。验证了皱纹盘鲍个体水平下两种标记方法的有效性及适用性,特别是对大规格苗种标记后生长、存活等性状无显著影响。研究结果将为皱纹盘鲍人工选育以及底播增养殖等工作提供有益指导。  相似文献   
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科技名词中文译名标准化和规范化工作是推动我国科技进步和科学知识传播的重要基础。新的科学概念和技术名词层出不穷,如何及时发现并确定新生术语的中文译名是一项普遍的社会需求。介绍了一套全新的天文学英语新词自动提取系统。该系统综合使用脚本过滤、术语识别、正则表达匹配等多种方法,能够自动追踪Ar Xiv论文数据库的更新,分析天文学论文的内容,生成推荐术语列表,从而将学科专家从繁重的科技新词收集整理工作中解放出来,把有限的精力集中到更能体现专业素养的新词审定工作当中。这个系统将为推动天文学等基础学科的新词收集,乃至学科标准化等工作发挥积极作用。  相似文献   
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Understanding movement behaviour is essential for effective management of fishery species. Dart tags were used to study coastal movement patterns of white steenbras Lithognathus lithognathus, an overexploited seabream (Sparidae) in South Africa. In total, 6 962 fish (190–1 080 mm fork length) were tagged throughout the species’ distributional range, in four long-term fish-tagging programmes. The predominant behaviour recorded was residency, with relatively short-ranging movements. More than 60% of the 351 recaptured fish were recaptured within 1 km of their tagging site, some of which were at liberty in excess of three years. Most of the juveniles (93.9%), subadults (71.7%) and adults (64.0%) were recaptured within 10 km. Occasional long-distance movements of up to 800 km were recorded. Recapture distances were positively, but weakly, correlated with fish fork length (n = 257 fish measured at recapture; r2 = 0.166, p < 0.001). Low levels of connectivity among coastal areas suggest that large-scale annual spawning migrations, as previously hypothesised for this species, are unlikely, which raises the possibility of multiple spawning sites. Seventy-seven percent of L. lithognathus tagged within three marine protected areas (MPAs) were recaptured within the same MPA, suggesting that area closures provide protection for L. lithognathus through the post-estuarine juvenile, subadult and adult life stages. We confirm that the country’s current network of coastal MPAs plays a vital role in sustaining this species, and suggest that additional closures, or otherwise substantial reductions in catch rates, are necessary for the species’ recovery.  相似文献   
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The seasonal range of sea temperature on the New Zealand shelf   总被引:1,自引:1,他引:0  
Sea water temperatures measured over the New Zealand continental shelf in summer and winter 1967 are compared and discussed.  相似文献   
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Two juvenile slender tuna Allothunnus fallai Serventy, 278 mm and 282 mm fork length, were identified from a catch by a purse seiner 23 km off the Moko Hinau Islands, New Zealand, on 23 January 1974. As the slender tuna were observed to school in association with skipjack tuna Katsuwonus pelamis L., it is probable that adults also school, and could be available as a yet unexploited resource to New Zealand fishermen, especially to the south‐east of New Zealand.  相似文献   
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