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北黄海营养盐结构及限制作用时空分布特征分析   总被引:5,自引:0,他引:5  
根据2006-07~2007-10 4个航次的调查资料,分析讨论了春、夏、秋、冬四季北黄海营养盐结构分布变化特征及营养盐限制状况.结果表明:春夏季表层,10 m层N/P,Si/N和Si/P值分布变化较大,呈现辽东半岛和山东半岛近岸高中部海域低的分布态势,高值区分别自鸭绿江口和夹河河口向外扩散,且均高于Redfield比值.秋冬季表层N/P,Si/N和Si/P值明显降低,且分布变化不大.10 m层,底层各季节分布相近,高值区位于鸭绿江口和夹河口附近.营养盐结构的分析表明,北黄海海域春夏季大部分站位表层浓度低于浮游植物生长的最低阈值,且春、夏、秋三季主要是受P的潜在限制,冬季营养盐限制状况消失.  相似文献   

3.
北黄海盆地中生代地层的地质特征和油气潜力(英文)   总被引:4,自引:1,他引:4  
位于山东半岛东北部的北黄海盆地沿东北方向可以延伸到朝鲜的西朝鲜湾盆地和安州盆地 ,而沿西南方向可以延伸到中国的胶莱盆地。长期以来该盆地的找油重点为第三系 ,结果收效甚微。2 0世纪 80年代末朝鲜在西朝鲜湾靠北黄海盆地一侧钻井数口且在中生代地层中发现了商业性油气流 ,自此中生代地层替代新生代第三纪地层成为人们关注的焦点 ,人们希望在北黄海盆地的中生代地层中也能找出商业性油气流。本文以李四光 ( 1 979)划分的新华夏系第二隆起带理论为指导 ,将胶莱盆地、北黄海盆地、西朝鲜湾盆地和安州盆地作为一个整体进行考虑 ,在详细分析了安州盆地、西朝鲜湾盆地和胶莱盆地的中生代地层分布、油气潜力及其类比关系后认为 ,北黄海盆地在基底结构及其上覆盖层的沉积特征上应具有与安州盆地、西朝鲜湾盆地和胶莱盆地相似的特征。目前 ,西朝鲜湾盆地和胶莱盆地在中生代地层中已取得重要的油气发现和油气显示 ,而它们主要是由下白垩统和上侏罗统组成。因此 ,我们有理由相信 ,北黄海盆地的中生代地层很可能成为有远景的勘探靶区。  相似文献   

4.
通过对2006年夏季对北黄海的现场调查,对该海域磷的形态和分布特征进行了探讨.结果表明: 夏季北黄海海域总磷(TP)浓度的变化范围是0.00~1.63 μmol/L,其中溶解无机磷(DIP)是最主要的存在形式,占TP的44%,溶解有机磷(DOP)略低,颗粒磷(PP)最少,总磷的分布呈现由南向北逐渐增高的趋势.北黄海海域水体中各种形态磷(除DOP外)均是表层低于底层,表底层PP的含量相差不大, 表层以DOP为主要存在形态,而底层则以DIP为主,大部分DIP浓度高的区域恰好是DOP浓度的低值区,一定程度上存在着负相关关系(r=-0.34).这样的分布趋势除了受生物活动的影响外,在底部海域还与黄海冷水团密切相关.  相似文献   

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北黄海表层海水溶解态重金属的分布特征及其影响因素   总被引:1,自引:0,他引:1  
于2007年春季和秋季对我国北黄海海域进行调查,采取溶剂萃取-原子吸收分光光度法对海水中溶解态重金属Cu,Pb,Zn,Cd进行了分析.结果表明,北黄海表层海水中溶解态重金属的含量呈现出沿岸海区高,中央海区低,浓度自近岸向远海逐渐减少的趋势,受沿岸人类活动影响较为明显.除秋季个别站点的Pb,北黄海表层海水重金属含量均未超过国家一类海水水质标准,水质良好.  相似文献   

6.
Agglutinated tubes of the polychaete Owenia fusiformis Delle Chiaje and their adjacent sediment were analyzed with respect to grain size, particle composition and tube structure to assess whether these parameters reflect a specific relationship between tube and adjacent sediment. Tubes and sediments were sampled southwest off Helgoland Island (southeastern North Sea) in water depth of 35–37 m. Particle selection was studied using settling velocity and component analysis. Both methods clearly showed that O. fusiformis actively selects coarse particles for tube building. The ability for size selection seems to be fully developed immediately after the transition from pelagic to benthic life, as considerable differences in the composition of tube and adjacent sediments occurred over the whole sampled sediment depth. In both tube and surface sediments quartz was the dominating component (>80%). In contrast, heavy minerals, the second frequent component of the surface sediments, were used less frequently for tube building. Biogenic components (e.g. shell material, echinoid fragments, foraminifera) occurring rarely in the sediment are nevertheless preferred as components for tube building. As underlying selection criteria a combination of size and the existence of at least one flattened surface that can be attached to the tube may be assumed.  相似文献   

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北黄海大气颗粒态营养元素的季节分布特征   总被引:1,自引:0,他引:1  
2006年7月~2007年10月对北黄海海域大气气溶胶及其负载的营养元素在春、夏、秋、冬4个季节的浓度分布进行了调查.结果显示,大气总悬浮颗粒物(TSP)、大气颗粒态总碳、钠、钙、镁、氮和磷都呈现出明显的季节变化,但是不同元素的季节分布规律不同.TSP、总碳和氮浓度都是春冬季较高,秋季次之,夏季最低.钠的季节变化与TSP不同,为夏季>冬季>春季>秋季,水溶性钙和镁分别呈现出春季>秋季>冬季>夏季及秋季>冬季>春季>夏季的季节变化.而水溶性磷酸盐浓度夏季最高,春季次之,秋冬季浓度很低.春、夏、秋、冬4季TSP、总碳和氮在不同采样海域的分布特征类似,即在离岸较近海域采集的样品TSP浓度较高,尤其是靠近辽东半岛和山东半岛海域.钠在不同采样海域的分布与TSP完全不同.各航次内钙、镁在不同采样海域的分布特征较复杂,呈现出与TSP和钠都不尽相同的分布特征.  相似文献   

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Laboratory and in situ experiments were performed to assess the use of bromide as a tracer forin situ studies of benthic solute exchange. Bromide was used in the benthic chamber lander ‘ Elinor ’ for flux measurements in coastal sediments of the German Bight, Kiel Bight and Skagerrak (28–700 m water depth). Tracer and total oxygen uptake were monitored simultaneously in the same chamber incubation. Concurrently, in situ oxygen micro-profiles were recorded at the same locations by the profiling lander ‘ Profilur ’. Deployment in an anoxic silt (Kiel Bight) confirmed that in the absence of bioturbation and advection, tracer transport into the sediment was driven solely by molecular diffusion. This flux could be well described by a simple box model accounting for molecular diffusion only. In oxic sediments (German Bight and Skagerrak) enhanced exchange of bromide tracer due to bioirrigation parallelled enhanced oxygen uptake equivalent to a 4-fold molecular diffusive flux. Our experiments showed that incubations can be short. Depending on irrigation activity of the fauna, however, incubation length should exceed 3 h in order to provide a useful data base for flux calculations. The method demonstrating caveats is discussed and indicate possible improvements. The results show how the bromide tracer addition can be used as a tool for determining solute fluxes exceeding diffusive flux in benthic chamber incubations.  相似文献   

11.
Vertical distributions of coccolithophores were observed in the depth range 0–50 m in the western subarctic Pacific and western Bering Sea in summer, 1997. Thirty-five species of coccolithophores were collected. Overall, Emiliania huxleyi var. huxleyi was the most abundant taxon, accounting for 82.8% of all coccolithophores, although it was less abundant in the western Bering Sea. Maximum abundance of this species was found in an area south of 41°N and east of 175°E (Transition Zone) reaching >10,000 cells L−1 in the water column. In addition to this species, Coccolithus pelagicus f. pelagicus, which accounted for 4.2% of the assemblage, was representative of the coccolithophore standing crop in the western part of the subarctic Pacific. Coccolithus pelagicus f. hyalinus was relatively abundant in the Bering Sea, accounting for 2.6% of the assemblage. Coccolithophore standing crops in the top 50 m were high south of 41°N (>241 × 106 cells m−2) and east of 170°E (542 × 106 cells m−2) where temperatures were higher than 12°C and salinities were greater than 34.2. The lowest standing crop was observed in the Bering Sea and Oyashio areas where temperatures were lower than 6–10°C and salinities were less than 33.0. From the coccolithophore volumes, the calcite stocks in the Transition, Subarctic, and the Bering Sea regions were estimated to be 73.0, 9.7, and 6.9 mg m−2, respectively, corresponding to calcite fluxes of 3.6, 0.5, and 0.3 mg m−2d−1 using Stoke's Law. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
The sediment at the interface immediately beneath the water column is distinct from deeper-lying sediments in its properties and, at least quantitatively, in the processes driving diagenesis. Progress in understanding the sediment-water interface can be based on consideration of fundamentals of biogeochemical particle / fluid interactions and on application of certain biological techniques especially suited to this challenging portion of the sediment column. This article reports results achieved by combining theoretical fundamentals and specialized experimental techniques in the study of the interface from selected depositional environments. For fine-grained and sandy deposits from fresh-water to coastal marine environments, the interface is characterized by exaggerated microrelief, great porosity, and significant biological alteration. Additional application of this research approach is poised to further our understanding of engineering, and acoustic and xenochemical responses of sedimentary materials, with special emphasis on the influence of the bio-organic phase of the interface upon its fabric and physical properties.  相似文献   

13.
The sediment at the interface immediately beneath the water column is distinct from deeper-lying sediments in its properties and, at least quantitatively, in the processes driving diagenesis. Progress in understanding the sediment-water interface can be based on consideration of fundamentals of biogeochemical particle / fluid interactions and on application of certain biological techniques especially suited to this challenging portion of the sediment column. This article reports results achieved by combining theoretical fundamentals and specialized experimental techniques in the study of the interface from selected depositional environments. For fine-grained and sandy deposits from fresh-water to coastal marine environments, the interface is characterized by exaggerated microrelief, great porosity, and significant biological alteration. Additional application of this research approach is poised to further our understanding of engineering, and acoustic and xenochemical responses of sedimentary materials, with special emphasis on the influence of the bio-organic phase of the interface upon its fabric and physical properties.  相似文献   

14.
2004年北太平洋柔鱼钓产量分析及作业渔场与表温的关系   总被引:3,自引:0,他引:3  
根据2004年5—11月我国鱿钓船在北太平洋生产数据,结合表温资料,按经纬度1°×1°的格式,利用Marineexplorer4.0软件作图进行分析。结果表明,5—7月在160°E以东海域作业,产量较低;8—10月在150°—160°E海域作业,为生产作业的产量高峰期,占总产量的62.5%;11月在150oE以西海域作业,产量也较低。在150°E以西海域CPUE最高,150°—160°E中部海域次之,160°E以东海域最低。作业渔场的适宜表温呈现出季节性变化。各月适宜表温分别为:5月12℃~14℃;6月15℃~16℃;7月14℃~16℃;8月18℃~19℃;9月16℃~17℃;10月15℃~16℃;11月12℃~13℃。K-S检验表明,上述表温可作为寻找中心渔场的指标。  相似文献   

15.
We report the results from a 250 km long transect, from the Danish coast to the North Sea at 55°30′ N, which was sampled every 32 km in order to study the composition and distribution of phytoplankton, and their dependence on the distance from the coast, depth and other environmental factors. Altogether 144 species of algae were identified by light, epifluorescence and electron microscopy. Some ecological preferences were found on the basis of measured environmental parameters and compared with the literature. Possible controlling mechanisms for the distribution patterns of the plankton algae were analyzed by multivariate statistics. Only distance from the coast was found to be a significant factor for algal distribution along the transect. Three main areas of the transect were found: the coastal, middle and oceanic areas. Diatoms, mainly the centric ones, were the most abundant group of algae. The other less abundant groups were Dinophyceae, Dictyochophyceae, Prasinophyceae and Chlorophyceae. The pattern of distribution of diatoms and dinophytes along the transect was more or less similar, with larger numbers of cells found close to both the eastern and western parts of the transect, although the species composition was different. Some species were found to prefer coastal waters, other species were characterized as oceanic, and several species were found at all stations. Porosira glacialis showed an atypical distribution along the transect, with highest abundances at both coastal and oceanic stations.  相似文献   

16.
The sandy quartzose parts of the Utsira Formation, the Middle Miocene to mid Pliocene Utsira Sand, extends north–south along the Viking Graben near the UK/Norwegian median line for more than 450 km and 75–130 km east–west. The Utsira Sand is located in basin-restricted seismic depocentres, east of and below prograding sandy units from the Shetland Platform area with Hutton Sands. The Utsira Sand reaches thicknesses up to ca. 300 m in the southern depocentre and 200 m in the two northern depocentres with sedimentation rates up to 2–4 cm/ka. Succeeding Plio–Pleistocene is divided into seismic units, including Base Upper Pliocene, Shale Drape, Prograding Complex and Pleistocene. The units mainly consist of clay, but locally minor sands occur, especially at toes of prograding clinoforms (bottom-set sands) and in the Pleistocene parts, and the total thickness covering the Utsira Sand is in most places more than 800 m, but thins towards the margins.  相似文献   

17.
秘鲁外海茎柔鱼渔场时空分布分析   总被引:3,自引:0,他引:3  
秘鲁外海茎柔鱼是重要的经济性种类,掌握其渔场时空分布规律有助于资源的合理利用。本文根据2003—2004年和2006—2009年我国鱿钓船在秘鲁外海的生产统计和海洋表面温度(SST)等资料,使用空间距离和聚类分析的方法,对其各年间渔场时空分布进行分析比较。结果表明,各年产量重心的分布都存在一定差异,产量重心在经度上随月份整体上呈现向西移动的趋势,在纬度方向上1~6月整体上呈向北移动的趋势,7~12月则表现出向南移动的趋势。聚类分析表明,2003、2006和2008年;2004、2007和2009年空间分布格局各为一类。空间距离分析表明,2006和2009年产量重心差异最大,其中前者平均产量重心为82°23′W、12°53′S,后者为81°47′W、14°27′S,南北相差约1.5个纬度。研究认为,渔场分布的月间变化是由茎柔鱼南北洄游所引起的,年间渔场分布差异与SST等海洋环境关系密切。  相似文献   

18.
纪焕红  叶属峰  刘星  洪君超 《海洋通报》2007,26(1):55-60,88
根据2004年5月、8月、11月和2005年2月南麂列岛海洋自然保护区海域调查资料,阐述了该海域浮游动物丰度和生物量的时空分布,探讨了其与环境因子的关系,并分析了保护区建区14a后丰度和生物量的变化以及不同季节生态类群丰度的组成特点。结果表明,浮游动物丰度和生物量季节变化明显,8月丰度最高,为(267.05±100.94)ind./m3,其他依次为11月、5月和2月;5月生物量最高,为(403.64±331.41)mg/m3,其他依次为8月、11月和2月;相关性分析表明,浮游动物丰度与生物量之间存在明显的正相关,相关系数为0.763,丰度、生物量与水温呈显著的正相关;与无机氮、活性磷酸盐表现为负相关;与浮游植物细胞丰度和叶绿素a含量未表现出相关性;与1990年相比,2004年春季浮游动物丰度和生物量均有所下降,秋季变化不大;不同季节各生物类群丰度和百分比均有差异。  相似文献   

19.
Nocturnal variations of zooplankton abundance and hydrographic conditions were examined at three locations (centre, north shore and south shore) in Phosphorescent Bay, Puerto Rico, from May 1992 through April 1993. Seven taxa accounted for approximately 96% of the annual mean zooplankton abundance:Oithonaspp. (43·5%),Acartia tonsa(31·5%), copepod nauplii (8·8%),Paracalanusspp.(6·7%), gastropod veligers (2·5%), larvaceans (1·7%) andPseudo-diaptomus cokeri(1·6%). Copepods dominated numerically throughout the year and comprised 94·3% of total zooplankton. Higher abundance of zooplankton (mean±1 SD=252 259±176 797 individuals m−3) was associated with cool water temperatures (24·9–27·4 °C) and dry conditions (0·3–2·9 cm precipitation/month) which prevailed between December and March relative to the period between April and November (warm/wet season) (mean±1 SD=59 773±26 861 individuals m−3), when temperature and precipitation were higher (27·3–30·3 °C, 3·1–20·6 cm month−1). Fluctuations of zooplankton populations, particularly copepods, followed progressive increments in chlorophyllaconcentrations. This abundance pattern was consistent at the three sampling stations. Zooplankton abundance was higher on the north shore of the bay. The taxonomic composition of zooplankton was similar at the sampling stations studied.  相似文献   

20.
In 1999, 2003 and 2007 macrofauna communities were sampled in three different areas (“Boxes”) of 10 × 10 nautical miles in the northern North Sea in order to study the temporal changes in community structure in relation to changes in temperature or changes in hydrography.  相似文献   

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