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昆虫是地球上多样性最高的生物类群,其物种数量超过所有生物物种数量的一半,在生态系统中具有重要功能,且与人类生活密切相关。理解昆虫多样性及地理分布格局对于科学研究和人类社会发展有重要意义。基于详细的文章资料梳理,本文总结了1950—2020年中国昆虫生物地理学领域文章发表趋势,并从昆虫物种多样性调查、昆虫区系研究、昆虫群落多样性、昆虫遗传多样性格局、昆虫地理分布格局等几个方面论述了中国昆虫生物地理研究的代表性研究进展。中国昆虫生物地理学研究几十年来取得了可喜的发展,但仍需重点加强几方面的思考和工作,包括整合性思维、时空尺度、科学问题的凝练、昆虫性状生物地理学、昆虫多样性和地理分布数据共享。 相似文献
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The species-rich genus Mustelus (smoothhounds) of the shark family Triakidae is one of the most bio-economically important groups of elasmobranchs in the world’s oceans. Despite the commercial value of Mustelus, the systematics of the group remains largely unresolved and there is no global review or synthesis of knowledge about the conservation status and conservation genetics of smoothhounds across all oceanic regions. Here, we analysed published studies as well as grey literature to gain insight into the biogeographic, ecological and behavioural factors that shape genetic diversity in smoothhounds, and we identify critical knowledge gaps. From a series of molecular phylogenetic studies it can be inferred that the genus Mustelus is paraphyletic and that the aplacental species evolved secondarily from the placental species of the genus. The increasing availability of genetic data aids in disentangling systematic issues, such that more meaningful morphological characters can be chosen for use in practical field-identification keys for co-occurring smoothhounds. An integrative taxonomic approach to the genus Mustelus may offer the best chance of recording and protecting the biodiversity of these sharks. Furthermore, it is evident that different smoothhound species exhibit unique gene-flow patterns, suggesting varying rates within species and hence that species-level conservation approaches would be most appropriate. Molecular studies have advanced our understanding of smoothhound biology (including reproductive traits), ecology and evolution. While many knowledge gaps remain, a crucial lesson from this review is that, when doing assessments on a molecular level, it is important to place genetic results in a broader context, by assimilating biological and ecological data, if definitive conclusions are to be drawn. 相似文献
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为了研究军曹鱼在急性低氧应激时体内物质代谢和组织器官机能状态变化,分别测定低氧胁迫前后血液生化指标的含量。结果表明:(1)急性低氧胁迫后,军曹鱼血清电解质含量呈不同程度升高,其中钠、氯和钙离子浓度与胁迫前差异极显著(P<0.01);钾离子浓度与胁迫前无显著性差异(P>0.05)。(2)急性低氧胁迫后,军曹鱼血清肝功能指标变化情况各异。其中,白蛋白含量与胁迫前略有降低,谷丙转氨酶和谷草转氨酶活性与胁迫前略有上升,但差异均不具有统计学意义(P>0.05),总蛋白含量显著低于胁迫前(P<0.05),白蛋白和球蛋白比值则显著高于胁迫前(P<0.05),碱性磷酸酶极显著低于胁迫前(P<0.01)。(3)急性低氧胁迫后,军曹鱼血清葡萄糖和肌酐浓度均呈升高的变化,且与胁迫前差异极显著(P<0.01)。(4)急性低氧胁迫后,血清肌酸激酶和乳酸脱氢酶活性均呈升高变化,肌酸激酶活性与胁迫前差异显著(P<0.05),乳酸脱氢酶活性与胁迫前差异极显著(P<0.01)。(5)低氧胁迫后,军曹鱼血脂指标变化情况各异,其中总胆固醇和高密度脂蛋白浓度呈极显著降低的变化(P<0.01),低密度脂蛋白浓度呈显著升高的变化(P<0.05),甘油三酯浓度略有升高,但不具有统计学意义(P>0.05)。研究表明,急性低氧胁迫后,军曹鱼大部分血液生化指标发生显著性变化,预示着肝脏、肾脏及心脏组织造成损伤,使其机能出现紊乱。 相似文献
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研究了实验室条件下原油水溶性组分(WSF)暴露对黑鲷、黄鳍鲷和褐菖鲉肝微粒体EROD活性的剂量-效应,时间-效应和恢复过程。实验结果表明,在剂量诱导实验中,褐菖鲉肝EROD活性在原油WSF浓度为50μg/dm3时呈现生物统计学上的显著差异,而黑鲷和黄鳍鲷肝EROD活性在75μg/dm3时才呈现生物统计学上的显著差异;褐菖鲉肝EROD活性诱导倍数最高,但黑鲷的诱导浓度范围较广。在时间诱导实验中,在40μg/dm3原油WSF暴露下黄鳍鲷肝EROD活性在2 d时首先呈现显著差异;三种鱼肝EROD活性均在第4天达到最高,并呈现显著性变化,此后随着暴露时间的延长而逐渐下降并接近对照组水平。在恢复实验中三种鱼肝EROD活性下降并恢复到对照组水平。研究结果表明:对于石油污染物,黑鲷、黄鳍鲷和褐菖鲉肝EROD活性都可以作为污染生化效应监测指标,然而就三种鱼类比较而言,褐菖鲉最敏感,更适合于作为石油类污染及其生化效应,尤其是低剂量效应的监测生物。 相似文献
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Amphipoda are a diverse and important faunal component of deep‐sea habitats worldwide. However, relatively little is known about species that are associated with cold‐water corals, in particular concerning their genetic diversity, population genetic processes, population differentiation, and potential host specificity. We exemplarily investigate these questions studying three pleustid species—Stenopleustes aff. malmgreni (Boeck, 1871), Stenopleustes aff. nodifera (Sars, 1883) and Neopleustes aff. boecki (Hansen, 1888)—that are associated with cold‐water corals and polychaete assemblages along the Reykjanes Ridge southwest of Iceland. We sequenced mitochondrial COI and performed ddRAD to study thousands of nuclear loci. These species and a pair of morphologically cryptic species within Stenopleustes aff. nodifera were consistently delimited by COI and ddRAD. We conclude that all of our studied species are new to science, raising the number of pleustids reported from cold‐water corals to six. Two species were collected only once, and these species exhibited high levels of inbreeding, suggesting little exchange with other populations, which might be a result of strong host specificity. The other two species were wider distributed, with very low differentiation among populations, even between populations separated by 130 km. These species showed signs of recent population expansions, possibly in relation to changes in the cold‐water coral associated ecosystem (e.g., due to glacial cycles and/or volcanic or geothermal activities). They had lower levels of inbreeding and were each associated with three different host coral species, which might facilitate dispersal and gene flow. Our results show divergent population genetic patterns for the studied pleustid species. These might be attributed to the species’ host specificity and highlight important differences among species with seemingly similar life‐styles. Species diversities appear to be greatly underestimated, limiting our abilities to truly assess the vulnerability of the fauna living in these threatened cold‐water coral habitats. 相似文献
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