南黄海和东海毛颚类生态特征的研究Ⅱ.群落特征          下载免费PDF全文

戴燕玉  林茂 《海洋学报》2007,29(3):90-97

在对南黄海和东海毛颚类生态特征的研究数量分布特征后的续篇.重点探讨调查区毛颚类群落性质和群落结构的特征及与海区环境因子的相关性.结果表明,本区共记录毛颚类28种,种类季节变化不明显,周年共有种达64.3%;但群落优势种则有季节差异与区域差异.毛颚类群落多样性指数(H')和均匀度(J')年均值分别为1.68和0.64.H'的平面分布表现出外部海区大于近岸海区的分布格局.在群落中存在4个生态类群,其中近海暖温带类群和广盐暖水类群可分别指示黄海水、浙江沿岸流和东海陆架混合水在南黄海和东海这两个海区的相互推移和消长过程.此外,从不同侧面的计算分析也表明,影响群落特征值(H')的主要因子是温度和盐度.群落性质是以近岸暖温带低盐种和暖水广布种为主,近岸暖水种和大洋暖水种占一定比例的暖温带-亚热带群落结构的特点.  相似文献   

Spatial and temporal variations of mesozooplankton in the Pearl River estuary, China   总被引：10，自引：0，他引：10  

K.Z. Li  J.Q. Yin  L.M. Huang  Y.H. Tan   《Estuarine, Coastal and Shelf Science》2006,67(4):543-552

This paper examines spatial and temporal variations of mesozooplankton abundance, biomass and community structure during three cruises of July 2002 (summer), January 2003 (winter), and April 2003 (spring) in the Pearl River estuary, China. Zooplankton abundance and biomass fluctuated widely and showed distinct heterogeneity in the Pearl River estuary. A total of 154 species were identified during three surveys. The number of zooplankton species richness was strongly linked to salinity. Hierarchical cluster analysis identified three zooplankton groups during this study. Estuarine, neritic and pelagic groups corresponded to the upper, middle and lower reaches in the Pearl River estuary. The difference among groups could be mainly ascribed to changes in the relative contributions of the dominant species. The fluctuations in the zooplankton abundance, biomass and community structure were determined by the interactive effects of freshwater inflow, tidal and coastal currents, chlorophyll a, salinity and temperature. Significant spatial variability in the distribution of zooplankton species, abundance and biomass can be ascribed to the virtual presence of a horizontal gradient in salinity.  相似文献   

泉州湾围海工程对海洋环境的影响   总被引：17，自引：3，他引：17  

陈彬  王金坑  张玉生  唐森铭  林景宏  郑凤武  张继伟 《台湾海峡》2004,23(2):192-198

采用现场调查资料与历史资料对比的方法,从海岸和海底地貌、水环境质量、海洋生物种类和群落结构等几方面分析了近几十年来福建泉州湾围海工程的环境效应.结果表明,围海工程促进了海滩的淤浅,减小了内湾的纳潮量和环境容量,使得泉州湾内湾水质恶化;其最终后果为围海工程附近海区生物种类多样性普遍降低,优势种和群落结构发生改变.  相似文献   

Crustal Thinning of the Northern Continental Margin of the South China Sea   总被引：2，自引：0，他引：2  

Ching-Hui Tsai  Shu-Kun Hsu  Yi-Ching Yeh  Chao-Shing Lee  Kanyuan Xia 《Marine Geophysical Researches》2004,25(1-2):63-78

Magnetic data suggest that the distribution of the oceanic crust in the northern South China Sea (SCS) may extend to about 21 °N and 118.5 °E. To examine the crustal features of the corresponding continent–ocean transition zone, we have studied the crustal structures of the northern continental margin of the SCS. We have also performed gravity modeling by using a simple four-layer crustal model to understand the geometry of the Moho surface and the crustal thicknesses beneath this transition zone. In general, we can distinguish the crustal structures of the study area into the continental crust, the thinned continental crust, and the oceanic crust. However, some volcanic intrusions or extrusions exist. Our results indicate the existence of oceanic crust in the northernmost SCS as observed by magnetic data. Accordingly, we have moved the continent–ocean boundary (COB) in the northeastern SCS from about 19 °N and 119.5 °E to 21 °N and 118.5 °E. Morphologically, the new COB is located along the base of the continental slope. The southeastward thinning of the continental crust in the study area is prominent. The average value of crustal thinning factor of the thinned continental crust zone is about 1.3–1.5. In the study region, the Moho depths generally vary from ca. 28 km to ca. 12 km and the crustal thicknesses vary from ca. 24 km to ca. 6 km; a regional maximum exists around the Dongsha Island. Our gravity modeling has shown that the oceanic crust in the northern SCS is slightly thicker than normal oceanic crust. This situation could be ascribed to the post-spreading volcanism or underplating in this region.  相似文献   

Species and Distribution of Mangroves in the Fujian Coastal Area     

王文卿  赵萌莉  邓传远  林鹏 《海洋通报(英文版)》2001,3(1)

On the basis of an investigation on the mangroves in Fujian from November 1998 to January 1999, the species composition, area, distribution, artificial afforestation of mangroves and the factors restricting the development of mangroves in Fujian are discussed in the paper. Some suggestions on how to develop mangroves in Fujian have been put forward.  相似文献   

新建水坝对下游已建水工建筑物的影响分析     

宋子东 《海岸工程》2005,24(1):59-62

分析了新建水坝及社会经济发展因素对坝下游水流及泥沙的影响，用一个简易河床模型来说明新建大坝后下游河床的演变规律，通过坝下游河床一般演变分析来阐述局部冲刷对已建水工建筑物基础的影响及对已建水工建筑基础的防护措施。  相似文献   

编织袋充填砂结构在围堰工程中的应用     

高存贵  孟琪 《海岸工程》2006,25(4):55-59

结合青岛市四方区围海造地工程的实例,分析了在厚度较大的软弱地基层上水下铺设大型编织布袋作为围堰的主体结构的优点和结构特点,重点介绍了施工工艺以及在施工过程中需注意的问题。  相似文献   

Relationships Between Community Structure of the Intertidal Macroinfauna and Sandy Beach Characteristics Along the Chilean Coast   总被引：2，自引：0，他引：2  

Eduardo Jaramillo  Heraldo Contreras  Cristian Duarte  & Pedro Quijón 《Marine Ecology》2001,22(4):323-342

Abstract. Eight sandy beaches were seasonally sampled along the coast of Chile, from ca. 21 to 42° S (about 3000 km) to study the relationship between community structure of the intertidal macroinfauna and beach characteristics. Sediment samples (0.1 m², 30 cm deep) were collected (July – September 1998 and December 1998 – January 1999) with plastic cylinders at 15 equally spaced levels along three replicated transects extending from above the drift line to the swash zone. The sediment was sieved through a 1 mm mesh and the organisms collected stored in 5 % formalin. To define beach types, Dean's parameter (Ω) was calculated from wave heights and periods, and fall velocity of sand particles from the swash zone. Crustaceans (mainly peracarids) were the most diverse group with 14 species, followed by polychaetes with 5 species. The talitrid amphipod Orchestoidea tuberculata , the cirolanid isopods Excirolana braziliensis and E. hirsuticauda and the anomuran decapod Emerita analoga were the most widely distributed and common species. Regression analyses between species richness, abundance and biomass of the whole macroinfauna versus sediment characteristics, beach face slopes and morphodynamic beach states showed no significant relationships. Thus, macroinfaunal community characteristics did not increase linearly from lower intermediate to higher intermediate or dissipative beach states as had been found before in Chile or in other coasts. A comparative analysis with data from sandy beaches of other world regions showed that the number of species inhabiting Chilean sandy beaches was generally lower, whereas total population abundances were generally higher compared with values reported elsewhere.  相似文献   

Hydroelastic Analysis of Very Large Floating Structures Using Plate Green Functions   总被引：4，自引：0，他引：4  

闫红梅  崔维成  刘应中 《中国海洋工程》2003,17(2)

1 .IntroductionRecentlygreatinteresthasbeenshowninthedevelopmentofverylargefloatingstructuressuchasMegaFloatofJapan (Isobe ,1 999)andMOBofUSA (Remmers ,1 999) .Owingtotheirextremelargesizeandgreatflexibility ,thecouplingbetweenthestructuraldeformationandfluidmotionissignifi cant.Thisisatypicalproblemofhydroelasticity .Efficientandaccurateestimationofthehydroelasticresponseofverylargefloatingstructuresinwavesisveryimportantfordesign .Manymethodshavebeenproposedinliteratureforthepredictiono…  相似文献   

闽中、闽东渔场扁舵鲣的资源生物学     

卢振彬  颜尤明  戴泉水 《台湾海峡》1992,(3)

本文以1981～1984年4～9月累计18个月在闵中、闵东渔场开展中上层鱼类资源开发性探捕调查的材料,报道了扁舵鲣的生态分布、群体结构和生活史主要特征。鱼群先后于4～7月由南而北进入本渔场,数量分布以5月为多;栖息的最适温、盐度分别为23.5～25.5℃和33～34;渔获群体由0～V龄组成;性成熟的最小年龄为Ⅰ龄,最小叉长271～280mm;生长参数L_∞=484.44mm,W_∞=2050.76g,K=0.5109,t_0=0.3598;瞬时自然死亡率为0.8937,开发比率为0.2138,属于轻度利用的鱼类资源,尚有较大的开发潜力。  相似文献