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1.
种的概念及种的界定与鉴定 总被引：1，自引：0，他引：1
种是生物学研究中的基本单位,但是种的概念和种的界定却一直是个难题。有关种的探讨延续了几个世纪,种概念的争论也持续了半个多世纪,但是至今仍无定论。种的界定近年来已成为种问题研究的焦点。尽管已提出了多种方法,但由于没有统一的种的概念,种的界定也一直没有标准的原则和统一的方法。种的鉴定随着DNA分类和DNA条形码的提出受到了越来越多的关注。快速准确的种鉴定/界定可以为分类、物种多样性以及遗传演化等研究提供有力的支持。本文综述了种的概念、种的界定和种的鉴定,主要评价了DNA条形码及整合分类法在种鉴定/界定中的应用。 相似文献
2.
The size of individual mining blocks for polymetallic nodule extraction seems to be rather small, not more than 100 km2 in the French mining claim. Even when adding an additional resedimentation zone to the directly impacted area, the size of the affected seabed would remain below 200 km2. We assume that even rare species in the abyss inhabit larger areas and propose discussions of the International Seabed Authority and other stakeholders for the different subregions on mining strategies from the perspective of exploitation versus species extinction and conservation. Although impacts of waste disposal at the abyssal seafloor are different from those of nodule mining, the 200 km2 concept may also be applied. 相似文献
3.
本文审查了中国南海感棒水母科、触丝水母科、玛拉水母科和帽冠水母科有关种类。记述了二个新种：隆脊真唇水母，新种Eucheilota carinata sp.nov.和南海盐生水母，新种Halopsis nanhaiensis sp.nov.和二个新记录属种：十字胃水母Staurostoma sp.及阿弗罗八拟杯水母Octophialucium aphrodite（Bigelow，1928）。编制了触丝水母科和玛拉水母科所有已知属和分种的检索表。此外，还简介了中国南海感棒水母科、触丝水母科、玛拉水母科和帽冠水母科已知种类名录及分布。模式标本保存于国家海洋局第三海洋研究所。 相似文献
4.
印度尼西亚北苏拉威西蓝碧海峡浮游动物种类组成及分布 总被引：1，自引：0，他引：1
Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to copepoda.Cnidaria followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m~3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs. 相似文献
5.
2010年秋季黄河口及其邻近海域中小型浮游动物的群落特征 总被引：3，自引：1，他引：2
为掌握黄河口邻近水域中小型浮游动物的现状并弥补此类重要浮游生物类群在以往调查研究中的欠缺, 于2010 年9 月在黄河口及其邻近海域用浅水Ⅱ型浮游生物网采集了浮游动物样品, 分析了中小型浮游动物的种类组成、丰度分布、优势种、生物多样性及群落结构。本次调查共鉴定浮游动物成体48 种, 浮游幼虫21 类, 桡足类和水螅水母为最主要的浮游动物类群, 分别占浮游动物成体种数的37.5%和20.8%。浮游动物丰度为2 300.1～266 232.0 个/m3, 平均丰度为37 074.3 个/m3。优势种(类)8种, 分别为夜光虫、强额拟哲水蚤、小拟哲水蚤、背针胸刺水蚤、异体住囊虫、桡足类无节幼虫、双壳类幼体以及腹足类幼体, 其中夜光虫为研究水域最主要优势种。对各站位物种组成和丰度进行分析,调查水域中小型浮游动物可划分为4 个组群, 各组群的分布格局受到水温、盐度和海流的共同影响。该研究为此水域生态系统的长期变化研究提供了重要基础资料和参考依据。 相似文献
6.
《Marine Policy》2016
This study reports three interaction events between the whale shark (Rhincodon typus) and fisheries in Brazilian waters. Two events were described as incidental captures in a gillnet fishery on the northern coast of Rio de Janeiro State, in southeastern Brazil. The last event took place at the Royal Charlotte Oceanic Bank (RCOB), in the southern region of Bahia State, where five fishermen filmed their interaction with a juvenile specimen. For one of the incidental captures, the fish was landed and consumed by locals, and for the other, the shark was released. In the RCOB, the fishermen touched the whale shark with their hands, wooden sticks and even rode on it. In addition, 74 interviews were conducted with fishermen from Bahia about sightings and possible interactions with R. typus. According to statements made by the fishermen, although not frequent, the conduct reported for the RCOB occasionally takes place in the region. Evaluating information of this nature is important to support government plans that regulate fishing activities in order to reduce incidental captures and the harassment of whale sharks. Encouraging the participation of fishermen in a collaborative monitoring program for R. typus may be a good way to better understand the threats to the species at a reduced cost, particularly for developing countries, such as Brazil. 相似文献
7.
André Padua Emilio Lanna Carla Zilberberg Paulo César de Paiva Michelle Klautau 《Marine Ecology》2013,34(1):56-61
Little is known about the recruitment and behaviour of sponge larvae, especially of the class Calcarea. The calcareous sponge Paraleucilla magna is very common in Southeast Brazil, where it is considered a cryptogenic species. This study quantified recruitment rates in shaded and illuminated habitats for 2 years in Rio de Janeiro, Brazil, and analyzed larval photoresponses of this species. Four structures, each containing a shaded and an illuminated surface, were exchanged every 3 months for 2 years. The number of recruits was quantified on each plate. In the laboratory, larvae of P. magna were placed in half‐shaded Petri dishes and the number of settlers in each side was counted after 24 h. Paraleucilla magna recruited continuously throughout the experiment. Recruits occurred in greater abundance on shaded surfaces than on illuminated surfaces, and the larvae were negatively phototactic in vitro. Despite the possible influence of other factors in the recruitment of sponges (such as sedimentation, competition and predation), the prevalence of P. magna in shaded habitats may also be related to larval choice. 相似文献
8.
为摸清福建兴化湾大型底栖动物的种类组成、生物多样性分布格局以及受扰动情况,于2013年7月、9月以及2014年2月、4月共四个航次进行了大型底栖动物调查。采用优势度指数、Shannon-Wiener多样性指数、Margalef’s丰富度指数和Pielou’s均匀度指数等方法,分析了该海域大型底栖动物的种类组成和生物多样性分布。结果表明,研究海域共鉴定出大型底栖动物132种,包括多毛类58种,甲壳类27种,软体动物33种,其他门类14种。四个季节的共同优势种均为多毛类,包括多鳃齿吻沙蚕(Nephtys polybranchia),寡鳃齿吻沙蚕(Nephtys oligobranchia),中蚓虫(Mediomastus californiensis)和异足索沙蚕(Lumbrineris heteropoda)。研究海域大型底栖动物的平均生物量为39.42g/m~2;平均栖息密度为311.67个/m~2;栖息密度和生物量平均值2014年4月最高(398个/m2,63.23g/m~2),2013年7月航次最低(252个/m2,7.77g/m~2)。不同站位,栖息密度和生物量不同。栖息密度最大值出现在1号站位(738个/m~2),最低值为12号站位(90个/m~2)。而生物量平均最大值出现在15号站位(108.17g/m~2),最低值出现在22号站位(8.72g/m~2)。丰富度指数、均匀度指数、Shannon-Wiener多样性指数的平均值分别为2.81、0.87和2.73,这三个指数,9月份均为最大,分别为3.20、0.93、3.12,4月份最小,分别为2.09、0.78、2.05。生物多样性指数和丰富度指数均表明福建兴化湾大型底栖动物群落受到一定的扰动。 相似文献
9.
Aquatic nonindigenous species (ANS) have dramatic impact on environmental, economic, social, cultural, and human health values in a variety of coastal, estuarine, and inland ecosystem. Despite efforts to develop biosecurity risk assessment frameworks for the improvement of ANS management, responsible agencies lack a standardized framework to identify and mitigate risk from ANS. This paper reviews the biosecurity risk assessment frameworks of seven international bodies, four regional bodies, and three countries and highlights the similarities, differences and deficiencies in their respective frameworks. Specific deficiencies found by the review include: (i) a lack of national implementation of the international and regional frameworks; (ii) gaps in ANS knowledge; (iii) insufficient guidance for various components of the risk assessment; (iv) limited number and scope of standards and measures related to ANS; and (v) inconsistent terminology between frameworks. To reduce the risk of ANS introductions, this paper concludes with a set of six recommendations to develop aquatic biosecurity risk frameworks that are both comprehensive and precautionary while also in accord with mandates established by other international bodies such as the World Trade Organization. 相似文献
10.
The Bering Sea is an area of high biological productivity, with large populations of sea-birds, demersal and pelagic fishes, so it seemed desirable to assess the bioaccumulation of trace metals in the ... 相似文献