Ichthyoplankton spatial pattern in the inner shelf off Bahía Blanca Estuary, SW Atlantic Ocean     

Mnica Susana Hoffmeyer  Menndez María Clara  Biancalana Florencia  Nizovoy Alicia Mabel  Torres Eduardo Ramn 《Estuarine, Coastal and Shelf Science》2009,84(3):181-392

This study focuses on the composition, abundance and distribution of ichthyoplankton in the inner shelf area off Bahía Blanca Estuary on the SW Atlantic Ocean during late spring. Eggs and larvae of Brevoortia aurea, Engraulis anchoita, Parona signata, Sciaenidae spp. – such as Cynoscion guatucupa and Micropogonias furnieri –, and Odontesthes argentinensis were found. Species richness was low probably as a result of season and shallow depths. Ichthyoplankton abundance reached values close to 10 000 per 10 m⁻³ (eggs) and 4000 per 10 m⁻³ (larvae) and displayed a spatial distribution pattern with maximum abundance values restricted to a band parallel to the coast. Differences between egg and larval patterns, probably derived from a different displacement and hydrodynamic behavior, were observed. Egg and larvae distribution patterns were found related with spawning areas and to directly depend on salinity and mesozooplankton. The larvae distribution pattern, in particular, was found to inversely depend on particulate organic carbon. In addition, the geographic location of egg and larvae maxima strongly coincided with a saline front reported for this area in springtime, thus suggesting a direct relationship with it.  相似文献   

饥饿胁迫条件下黑鮸（Miichthys miiuy）仔鱼的生长与存活过程研究     

单秀娟  窦硕增 《海洋与湖沼》2008,39(1):14-23

采用实验生态学方法研究了延迟投饵对黑鮸仔鱼摄食、存活生长及体成分组成的影响。结果表明,在24℃,仔鱼在3日龄时开口摄食,4日龄时卵黄囊吸收完毕,6日龄仔鱼如不能建立外源性营养即进入饥饿死亡不可逆点（PNR）,而延迟投饵3天（6日龄）以上的仔鱼在8日龄前全部死亡。正常投喂仔鱼（16％）和延迟投饵1天仔鱼（15％）的存活率明显高于延迟2天投饵仔鱼（9％）。它们的高死亡（日死亡率为5％-6.5％）集中发生在3-8日龄期间,但低于3-7日龄内延迟投饵3天和完全饥饿仔鱼（日死亡率为18.5％）。在7日龄时,正常投喂仔鱼（9.9％）的特殊生长率（SGR）明显高于延迟投饵仔鱼（4.6％-8.4％）。在36日龄时,正常投喂仔鱼与延迟投饵1天仔鱼之间的生长差异消失,与延迟投饵2天的仔鱼之间的生长差异显著。延迟投饵引起开口摄食阶段仔鱼体内脂肪和蛋白质含量明显减少,但延迟投饵1-2天的存活仔鱼在后期发育过程中可以达到正常投饵仔鱼的营养水平。因此,不论在养殖条件下还是在自然水域,黑鮸仔鱼必须在开口后2天之内建立起主动摄食能力才可能保证其仔鱼的正常发育、生长和存活。  相似文献   

5种药物对方斑东风螺面盘幼虫的急性毒性   总被引：2，自引：0，他引：2  

李雷斌  刘志刚 《广东海洋大学学报》2008,28(3)

在水温29.0～29.5℃、盐度28.5条件下,采用静水试验法对5种常用药物对方斑东风螺面盘幼虫的急性毒性进行了研究。结果表明:各种药物的24 hLC50、48 hLC50、96 hLC50和安全浓度分别为:高锰酸钾1.71、1.04、0.55和0.115 mg.L-1,新洁尔灭78.58、28.90、6.06和1.17 mg/L,硫酸锌4.52、2.36、0.62和0.193 mg/L,制霉素2.36×104、1.46×104、0.64×104和0.168×104 U.L-1,甲醛10.9、7.11、3.66和0.908μL.L-1。  相似文献   

Multi-scale approach to the environmental factors effects on spatio-temporal variability of Chironomus salinarius (Diptera: Chironomidae) in a French coastal lagoon     

V. Cartier  C. ClaretR. Garnier  S. FayolleE. Franquet 《Estuarine, Coastal and Shelf Science》2010

The complexity of the relationships between environmental factors and organisms can be revealed by sampling designs which consider the contribution to variability of different temporal and spatial scales, compared to total variability. From a management perspective, a multi-scale approach can lead to time-saving.  相似文献   

Distribution and retention of Petrolisthes armatus in a coastal plain estuary: The role of vertical movement in larval transport     

Charles E. Tilburg  Jennie E. Seay  T. Dale Bishop  Harlan L. Miller III  Christof Meile 《Estuarine, Coastal and Shelf Science》2010

Since transport of planktonic larvae is essential to the maintenance and expansion of many marine species, we examined the spatial and temporal distribution of green porcelain crab Petrolisthes armatus (Gibbes, 1850) larvae and the possible underlying physical and behavioral mechanisms using a combination of field observations and numerical modeling. The field study consisted of observations of larval abundance and distribution as well as hydrographic surveys of the Satilla River estuary on the east coast of the USA in August 2006. Larvae were found throughout the water column within the tributaries but primarily at depth in the main river. A numerical model was used to examine the effect of flow and possible larval behavior responsible for the observed distribution and the consequences for larval retention in the estuary. Model results that included downward larval movement are consistent with the field observations, supporting the hypothesis that P. armatus larvae vertically migrate within the water column, which aids in their retention within the estuary.  相似文献   

中国近海洄游日本鳗鲡(Anguilla japonica)玻璃鳗肠道微生物菌群分析          下载免费PDF全文

姜之信  李慷  巴旭冰  曾祥标  刘利平 《海洋与湖沼》2023,54(6):1728-1736

为研究长江口日本鳗鲡玻璃鳗肠道菌群的结构与多样性特征,初步探究野生鳗鲡仔鱼的营养需求,分别采集浙江台州市、舟山市以及江苏盐城市邻近海域的玻璃鳗样品,利用16S rDNA扩增子测序技术,分析三个采样点玻璃鳗肠道优势菌群及营养代谢相关的功能差异。结果显示,三个采样点的玻璃鳗肠道菌群均以变形菌门(Proteobacteria, 68.7%～82.0%)和放线菌门(Actinobacteria,4.2%～19.0%)为主要优势菌门。在属分类水平上,不动杆菌属(Acinetobacter, 12.4%～17.3%)和假单胞菌属(Pseudomonas, 8.07%～13.03%)丰度较高,属固定优势菌属。此外,每个采样点样本中都含有丰富的独特细菌群,包括台州市的气单胞菌属(Aeromonas)、舟山市的内生单胞属(Endozoicomonas)和丙酸杆菌属(Cutibacterium)以及盐城市的嗜冷杆菌属(Psychrobacter)和稳杆菌属(Empedobacter),推测是受采样点不同水环境因素影响。不动杆菌、假单胞菌、内生单胞菌等菌属在多种鱼类肠道中有着消化蛋白质的功能,气单胞菌虽属于...  相似文献