南麂列岛中华蛸(Octopus sinensis)形态与遗传多样性分析     

李嘉华  陈舜  陈万东  谢尚微  倪孝品  郑小东 《海洋与湖沼》2022,53(2):486-495

2020年6~12月在南麂列岛采捕一种中大型章鱼44只,描述了形态特征,采用多元分析方法分析了形态多样性,并比较了与真蛸的差异,利用线粒体细胞色素氧化酶亚基I(COI)基因序列构建了系统发育树,并计算了Kimura-2-Parameter(K2P)遗传距离。结果表明,此种章鱼形态特征与中华蛸基本一致,而与真蛸存在显著的形态差异:其第二、三对腕的扩大吸盘位于第12~15个吸盘之间,而真蛸则位于第15~19个吸盘之间;茎化腕吸盘数少于真蛸;舌叶指数小于真蛸。主成分分析与判别分析能将真蛸群体显著区分开,判别准确率为100%,而其余四个群体(南麂列岛与三个中华蛸群体)间存在重叠;聚类分析表明南麂列岛群体与中华蛸更近,二者均与真蛸存在较大距离。在遗传多样性分析中,南麂列岛群体单倍型4个,单倍型多样性水平为0.320±0.121,多态位点6个,核苷酸多样性指数为0.001 11;系统发育树表明,该群体与中华蛸亲缘关系最近,K2P遗传距离0.14%,而与真蛸复合体其他类型为2.96%~12.11%。因此,从形态和分子水平鉴定南麂列岛章鱼为中华蛸。  相似文献   

Suspended sediment transport and deposition in the Zhoushan Archipelago sea area     

Rijun Hu  Jianzheng Wu  Longhai Zhu  Fang Ma 《中国海洋大学学报(英文版)》2009,8(4):343-351

The transport mechanism and settlement characteristics of suspended sediments are analyzed in this article on the basis of measured data. Results indicate that the concentration and flux of suspended sediments decrease sharply from Hangzhou Bay to the offshore area. Suspended sediment transport is mainly controlled by advection transport and gravitational circulation transport. The settling velocity of suspended sediments gradually decreases from Hangzhou Bay to the offshore area. The settlement of suspended sediments mainly takes place during the turning phase of the tidal currents.  相似文献   

崎岖列岛海区水沙特征及近期冲淤演变   总被引：3，自引：0，他引：3  

俞航  陈沈良  谷国传 《海岸工程》2008,27(1):10-20

利用1999年冬季水文泥沙观测资料，分析了崎岖列岛海区冬季水动力条件及悬沙特征；根据1998，2004，2005和2006年水下地形资料，计算了该海区冲淤量及冲淤速率，探讨了研究区域近年来冲淤演变的特征及规律，得出最近8年来海区总体呈冲蚀状态、岛链峡道西部水城和岛闻汉道出现淤积的状况，出现这一状况的原因主要与长江入海泥沙减少和洋山港工程有关。洋山港堵汉工程改变了局部水动力环境，造成岛链峡道西部水域和岛间汊道的冲淤变化；长江入海泥沙减少和长江口、杭州湾大片围垦截沙，削减了对崎岖列岛海区的泥沙补给，导致了海区总体呈冲刷趋势。  相似文献   

The effects of resolving the Canadian Arctic Archipelago in a finite element sea ice model   总被引：1，自引：0，他引：1  

Olivier Lietaer  Thierry Fichefet  Vincent Legat 《Ocean Modelling》2008,24(3-4):140-152

Though narrow straits may have a strong influence on the large-scale sea ice mass balance, they are often crudely represented in coarse resolution sea ice models. Unstructured meshes, with their natural ability to fit boundaries and locally increase the mesh resolution, propose an alternative framework to capture the complex oceanic areas formed by coasts and islands. In this paper, we develop a finite element sea ice model to investigate the sensitivity of the Arctic sea ice cover features to the resolution of the narrow straits constituting the Canadian Arctic Archipelago. The model is a two-level dynamic-thermodynamic sea ice model, including a viscous-plastic rheology. It is run over 1979–2005, forced by daily NCEP/NCAR reanalysis data. Confronting qualitatively numerical experiments with observations shows a good agreement with satellite and buoys measurements. Due to its simple representation of the oceanic interactions, the model overestimates the sea ice extent during winter in the southernmost parts of the Arctic, while the Baffin Bay and Kara Sea remain ice-covered during summer. In order to isolate the benefits from resolving the Canadian Arctic Archipelago, a numerical experiment is performed where we artificially close the archipelago. Focusing on the large-scale sea ice thickness pattern, no significant change is found in our model, except in the close surroundings of the archipelago. However, the local and short-term influences of the ice exchanges are nonnegligible. In particular, we show that the ice volume associated to the Canadian Arctic Archipelago represents 10% of the Northern Hemisphere sea ice volume and that the annual mean ice export towards Baffin Bay amounts to 125 km³ yr⁻¹, which may play an important role on the convective overturning in the Labrador Sea.  相似文献   

南麂海区美国红鱼网箱养殖试验     

蔡厚才 《海洋学研究》2001,19(4):28-34

1996年 1 0月底从青岛引进平均体长为 2 .1 cm、体重为 0 .5 g的美国红鱼苗 75 0 0尾在南麂海区进行网箱养殖试验 ,养至 1 997年 1 2月 2 5日止 ,其平均体长为 3 2 .8cm,尾均重达6 92 .8g,鱼苗期成活率为 5 5 .7% ,养成期成活率达 98.4% ,饵料系数为 7.2 2～ 9.5 9。此外 ,还对该鱼的放养时间、苗种培育、鱼病防治、人工增殖以及网箱抗风浪措施等问题进行了初步探讨  相似文献   

南麂列岛环境质量调查与潮间带生态研究   总被引：3，自引：2，他引：3  

陈国通  杨晓兰 《海洋学研究》1994,12(2):1-15

１９９２年５月～１９９３年３月对南麂列岛潮间带１７条断面和本岛陆域环境进行了全面的生态调查和环境质量评价。共获大型底栖动物２７８种，大型藻类１２１种，微小型藻类１５５种。研究结果表明，本区种类组成以软体动物最为丰富，生物数量以甲壳动物占绝对优势。区系特点与福建、广东沿岸较为相似。生物量以春季为高，栖息密度在秋季有一明显高峰。生物量的大小顺序为开敞岩礁大于隐蔽岩礁大于巨砾大于泥滩大于沙滩。种类组成、数量分布和群落结构与底质类型、波浪作用关系密切。文中还对生物的地域断裂分布现象作了探讨，对环境质量保护问题提出了建议。  相似文献   

Garnet-forming reactions and recrystallization in high-grade mylonite zones, MacRobertson Land, east Antarctica     

R. W. WHITE  G. L. CLARKE 《Journal of Metamorphic Geology》1994,12(6):853-865

Proterozoic granulite facies gneisses in MacRobertson Land, east Antarctica, are cut by numerous D5 mylonite-ultramylonite zones of probable Cambrian age. In garnet-absent mafic two-pyroxene gneisses and garnet-bearing charnockitic orthogneisses, the mylonite-ultramylonite zones are characterized by the growth of garnet at the expense of ilmenite, pyroxene and plagioclase. Textures within each mylonite zone can vary from protomylonitic to ultramylonitic. A range of mineral textures involving M5 garnet is developed corresponding to variations in deformation intensity. In protomylonites, garnet occurs as coronas on orthopyroxene-plagioclase and ilmenite-plagioclase boundaries, and as overgrowths on earlier garnet. In ultramylonites, fine-grained orthopyroxene-plagioclase-garnet ± quartz ± clinopyroxene intergrowths and poikilitic garnet are common. Garnet growth in all shear zones is accompanied by shifts in the compositions of neoblastic minerals occurring with garnet, consistent with local chemical equilibrium having been attained during recrystallization. Mylonitization is inferred to have occurred at P ∼ 6.5 kbar. Temperature estimates for M5 vary between 550 and 797 C, which may reflect variations and uncertainties associated with the calibrations used and/or partial re-equilibration during cooling. The presence of post-tectonic, coronate garnet in some mylonite zones indicates that garnet continued to form exclusively in the mylonite zones after movement had ceased and is interpreted to reflect the effects of localized strain heating.  相似文献   

Pre- and post-1998 ENSO records of shallow-water octocorals (Alcyonacea) in the Chagos Archipelago     

Schleyer MH  Benayahu Y 《Marine pollution bulletin》2010,60(12):2197-2200

When compared, principal octocorals collected in the Chagos Archipelago before and after the 1998 ENSO shared many common taxa. While a few discontinuities in their biodiversity revealed subtle changes in more persistent genera (Lobophytum, Sarcophyton), some fast-growing “fugitive” genera (e.g. Cespitularia, Efflatounaria, Heteroxenia) disappeared after the ENSO-related coral bleaching. Such transient fugitives might thus be eliminated from soft coral communities on isolated reef systems, possibly in the long term, by events of this nature. The appearance of Carijoa riseii, a species often considered a fouling organism, even an invasive, may well be indicative of reef degradation during the ENSO event. The post-ENSO recovery manifested by this fauna nevertheless gives cause for hope for their survival in the face of climate change.  相似文献   

南麂列岛海域沉积物中甲藻孢囊的多样性和分布     

尤胜炮  高寒  雷向东  萧云朴  顾海峰  佟蒙蒙 《海洋与湖沼》2016,47(2):460-467

南麂列岛地处亚热带海域,是台湾暖流和江浙沿岸流的交汇处,因而呈现出很好的生物多样性。据调查,南麂列岛附近海域已鉴定的浮游植物甲藻有53种,而到目前为止,对南麂列岛海域甲藻的休眠孢囊种类和分布的调查仍为空白。本文通过对2014年南麂列岛附近海域沉积物中甲藻孢囊的调查研究,在该海域共发现甲藻孢囊10属26种,其中,种类最多的是原多甲藻属(Protoperidinium),有10种;其次是斯氏藻属(Scrippsiella)和亚历山大藻属(Alexandrium),分别有4种,膝沟藻属(Gonyaulax)2种,舌甲藻属(Lingulodinium)、易碎藻属(Fragilidium)、扁甲藻属(Pyrophacus)、翼藻属(Diplopsalis)、裸甲藻属(Gymnodinium)和多沟藻属(Polykrikos)各1种。这些甲藻孢囊中,异养型和自养型甲藻孢囊各13种,自养型甲藻孢囊在数量上所占比例较大(79%)。2014年南麂列岛海域甲藻孢囊丰度较低,每毫升沉积物能检测出2—33个;夏、秋季的孢囊丰富度较高;岙口等相对开放海域的孢囊丰度明显高于岙内各站点。值得注意的是,三种有毒甲藻孢囊,塔玛/相似亚历山大藻(Alexandrium tamarense/affine),具刺膝沟藻(Gonyaulax spinifera)和多边舌甲藻(Lingulodinium polyedra)的孢囊也在样品中检出,并且分别占春季、夏季和秋季孢囊总丰度的37%、23%和27%。本研究为完善南麂列岛甲藻的物种多样性提供了依据。  相似文献   

A model to assess fundamental and realized carrying capacities of island ecosystem: A case study in the southern Miaodao Archipelago of China   总被引：2，自引：0，他引：2  

SHI Honghu  SHEN Chengcheng  ZHENG Wei  LI Fen  WANG Xiaoli  CHI Yuan  GUO Zhen  QIAO Mingyang  GAO Liyuan  DING Dewen 《海洋学报(英文版)》2016,35(2):56-67

Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island (EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island (FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago (SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone.  相似文献