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Sea Area (sea + area)
Kinds of Sea Area Selected AbstractsTracing recent invasions of the Ponto-Caspian mysid shrimp Hemimysis anomala across Europe and to North America with mitochondrial DNADIVERSITY AND DISTRIBUTIONS, Issue 2 2008Asta Audzijonyte ABSTRACT The mysid crustacean Hemimysis anomala (,bloody-red shrimp') is one of the most recent participants in the invasion of European inland waters by Ponto-Caspian species. Recently the species also became established in England and the Laurentian Great Lakes of North America. Using information from mitochondrial cytochrome oxidase I (COI) gene sequences, we traced the invasion pathways of H. anomala; the inferences were enabled by the observed phylogeographical subdivision among the source area populations in the estuaries of the Ponto-Caspian basin. The data distinguish two routes to northern and western Europe used by distinct lineages. One route has been to and through the Baltic Sea and further to the Rhine delta, probably from a population intentionally introduced to a Lithuanian water reservoir from the lower Dnieper River (NW Black Sea area) in 1960. The other lineage is derived from the Danube delta and has spread across the continent up the Danube River and further through the Main,Danube canal down to the Rhine River delta. Only the Danube lineage was found in England and in North America. The two lineages appear to have met secondarily and are now found intermixed at several sites in NW Europe, including the Rhine and waters linked with the man-made Mittellandkanal that interconnects the Rhine and Baltic drainage systems. [source] Detection of nodularin in flounders and cod from the Baltic SeaENVIRONMENTAL TOXICOLOGY, Issue 2 2001Vesa Sipiä Abstract The brackish water cyanobacterium Nodularia spumigena regularly forms waterblooms in the Baltic Sea. Many N. spumigena strains can produce nodularin, a hepatotoxic penta-peptide, which has caused several animal poisonings in the Baltic Sea area. To improve our understanding of nodularin bioaccumulation in aquatic organisms this study measured nodularin in flounder and cod caught from the Baltic Sea. Flounders were collected from the western Gulf of Finland in July 1996, September 1997, and September 1998, and from the Gulf of Bothnia in August 1997 and September 1998. Flounders were also collected from the coastal areas of Sweden in the Baltic Proper during September 1998. Cod were caught from the southern Baltic Sea in August 1998. Livers and muscles of the 1997 fish were isolated, extracted, and analysed for nodularin using high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) and protein phosphatase 1 (PP1) inhibition assay. Approximately 30,70 ng of nodularin/g dry weight (maximum value 140 ng/g) were found in the liver tissue samples by ELISA and PP1 inhibition. These concentrations were below the detection limit of HPLC. PP1 assay showed inhibition also in muscle samples, but this may due to other compounds present in the muscle extracts rather than NODLN or due to matrix interference. The recovery of nodularin from liver tissue with ELISA and PP1 assays was about 30%. Nodularin concentrations in samples are not corrected for recovery. Although the concentrations of nodularin found in this study are low further studies of nodularin are needed to assess possible bioaccumulation in brackish water food webs. © 2001 John Wiley & Sons, Inc. Environ Toxicol 16: 121,126, 2001 [source] Conservation goals and fisheries management units for Atlantic salmon in the Baltic Sea areaJOURNAL OF FISH BIOLOGY, Issue 2001M-L. Koljonen The effective application of genetic information in fisheries management strategies implies political goal setting taking both conservation and fisheries management into account. The concept of sustainable use as set out by the Convention on Biological Diversity offers a valuable starting point in this respect, since the criterion for it is defined as the maintenance of genetic diversity within each species. However, strategic decisions are also needed on the practical level, where the actual genetic information can be taken into account. Genetic factors, such as glacial differentiation, the postglacial genetic structure of populations, gene flow levels and the probability of the existence of adaptive differences, have an effect on the formation of conservation and management units and on the long-term strategy for the sustainable use of aspecies. The Atlantic salmon (Salmo salar) in the Baltic Sea area is treated here as an example of a complicated management problem with a highly hierarchical genetic structure associated with marked loss of naturally reproductive stocks, extensive hatchery production and an effective international offshore fishery. The implications of genetic factors for the conservation and management strategy of the Baltic salmon is discussed in the light of the goals set by the Convention on Biological Diversity, the Straddling Fish Stocks and Highly Migratory Fish Stocks Agreement, the Habitats Directive of the European Union and the International Baltic Sea Fishery Commission. [source] Phylogeographical structure, distribution and genetic variation of the green algae Ulva intestinalis and U. compressa (Chlorophyta) in the Baltic Sea areaMOLECULAR ECOLOGY, Issue 8 2004E. LESKINEN Abstract The marine algae Ulva intestinalis and U. compressa are morphologically plastic with many overlapping characters and are therefore difficult to distinguish from each other. The present distribution of U. intestinalis and U. compressa is investigated along the salinity gradient in the Baltic Sea area through analyses of internal transcribed spacer (ITS) sequence data. Also, the amount and distribution of intraspecific genetic polymorphism in the ITS region is studied allowing inferences on the phylogeographical pattern and postglacial recolonization of the Baltic Sea area. The data show that of the two species only U. intestinalis occurs in the Baltic Sea. The distribution of U. compressa is more restricted than previously reported, and it was not found in salinities lower than 15 ppt. All of Scandinavia and the Baltic Sea were covered with ice during the last ice age and the organisms in the Baltic Sea must have colonized the area after the ice had started to melt. The genetic diversity of U. intestinalis and U. compressa in the Baltic Sea and the neighbouring area was found to be reduced compared to that in the British Isles. This reduction may be the result of either a historical reduction of diversity or an adaptation of specific clones to the northern environmental conditions. [source] Matrilinear phylogeography of Atlantic salmon (Salmo salar L.) in Europe and postglacial colonization of the Baltic Sea areaMOLECULAR ECOLOGY, Issue 1 2001J. Nilsson Abstract Sixty-four samples from 46 salmon populations totalling 2369 specimens were used for polymerase chain reaction,restriction fragment length polymorphism (PCR,RFLP) analysis of the mitochondrial ND1 region. The final analyses included 3095 specimens from 60 populations in Northern Europe. A subsample was analysed by RFLP of ND3/4/5/6. Representative RFLP haplotypes from different parts of the distribution area were sequenced and the phylogeny of European haplotypes and their relations to the North American lineage was described. The four common European haplotypes derive from the ancestral ND1-BBBA (rooting the European clade to the North American) by one-step substitutions: AAAA < AABA < BBBA > BBBB. The Swedish west-coast populations differ from the geographically close southern Baltic, indicating absence of inward and limited outward gene flow through the Danish straits during the last 8000 years. Within the Baltic Sea, only three ND1 haplotypes were detected and there was no variation for ND3/4/5/6. In the whole southern Baltic and in lakes Vänern, Ladoga and Onega the haplotype AABA dominated. Proposed postglacial colonization routes to the Baltic Sea are discussed in relation to the haplotype distribution pattern. [source] NEWS FROM EU RESEARCH: BaSeFood: sustainable exploitation of bioactive components from the Black Sea Area traditional foodsNUTRITION BULLETIN, Issue 3 2010F. D'Antuono Summary The Sustainable exploitation of bioactive components from the Black Sea Area traditional foods (BaSeFood) is a 3-year collaborative research programme, funded by the 7th Framework Programme, launched on the 1st of April 2009. The project, which is coordinated by Dr Filippo D'Antuono (University of Bologna), consists of a research consortium of 13 partners, namely Italy (two), the United Kingdom, Greece, Portugal, Serbia and six Black Sea area countries: Russian Federation, Ukraine (two), Romania, Bulgaria, Turkey and Georgia. BaSeFood will contribute scientifically by studying the bioactive compounds within traditional foods of the Black Sea area using rigorous analytical and biological assays. The vast array of characteristics of traditional foods will be considered, as well as any associated consumer-perceived benefits, related to health claims, so that they can be properly understood by the consumer and exploited by food processors to produce more healthy traditional foods. [source] ISLANDSCAPES AND ,ISLANDNESS': THE PREHISTORIC ISLE OF MAN IN THE IRISH SEASCAPEOXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2008CATHERINE FRIEMAN Summary. This paper will explore the role of the Isle of Man in the prehistory of the Irish Sea area through an examination of its changing islandscape from the Neolithic through the Iron Age. It was far from insular during prehistory, but the social and economic interactions of prehistoric Manx people around the Irish Sea and beyond were heavily affected by their water-bound environment. The way that the prehistoric Manx perceived their boundaries and their coastal situation is reflected in their ritual and social landscape, their preferential use of coastal areas for monumental architecture, and in the choices they made with regard to the island landscape they inhabited. This culturally constructed sense of islandness allowed the prehistoric Manx people to maintain distinctive local cultures while still playing an active role in the larger Irish Sea region. [source] Places Of Transformation: Building Monuments From Water And Stone In The Neolithic Of The Irish SeaTHE JOURNAL OF THE ROYAL ANTHROPOLOGICAL INSTITUTE, Issue 1 2003CHRIS FOWLER Using the Irish Sea area as a case-study, we argue that both sites and landscapes can be understood as containing a series of components procured from the landscape and from human, animal, and object bodies. These components were organized in a way that commented on and related to specific cultural relationships between these different locations and through the substances found within them. This idea is explored by examining Neolithic monuments, material culture, and natural materials in southwest Wales, northwest Wales, the Isle of Man, and southwest Scotland. We trace some metaphorical schemes which were integral to Neolithic activity in this part of the Irish Sea. In particular, we highlight the metaphorical connections between water and stone in places associated with transformation, particularly the repeated transformation of human bodies. We suggest that the series of associations present in the Neolithic were not invested with a uniform meaning but, instead, were polyvalent, subject to conflicting interpretations, contextually specific and variable through both space and time. The relationship between these elements was therefore dependent on the contexts of their association. Nevertheless, the association of water and stone can be found repeatedly throughout the Neolithic world and may have been the medium of a powerful trope within broader conceptions of the world. This article is intended as a preliminary consideration of these issues (particularly the links between stone, mountains, water, quartz, shell, and human remains) and is offered as a thinking-point for ongoing research in this area. [source] Mesozoic-Cenozoic Tectonics of the Yellow Sea and Oil-Gas ExplorationACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2010Tianfeng WAN Abstract: The purpose of the present study was to study the tectonics of the Yellow Sea. Although oil-gas exploration has been undertaken for more than 30 years in the southern Yellow Sea, the exploration progress has achieved little. There are three tectonic periods with near N,S trending shortening and compression (260,200 Ma, 135,52 Ma and 23,0.78 Ma) and three tectonic periods with near E,W trending shortening and compression (200,135 Ma, 52,23 Ma and 0.78 Ma) at the Yellow Sea and adjacent areas during the Mesozoic and Cenozoic. The Indosinian tectonic period is the collision period between the Sino-Korean and Yangtze Plates, which formed the basic tectonic framework for the Yellow Sea area. There were strong intraplate deformations during the Yanshanian (200,135 Ma) and Sichuanian (135,52 Ma) periods with different tectonic models, which are also the main formation periods for endogenic metallic mineral deposits around the Yellow Sea. The three tectonic periods during the Cenozoic affect important influences for forming oil-gas reservoirs. The Eocene,Oligocene (52,23 Ma) is the main forming period for oil-gas sources. The Miocene,Early Pleistocene (23,0.78 Ma) was a period of favorable passage for oil-gas migration along NNE trending faults. Since the Middle Pleistocene (0.78 Ma) the NNE trending faults are closed and make good conditions for the reservation of oil-gas. The authors suggest that we pay more attention to the oil-gas exploration at the intersections between the NNE trending existing faults and Paleogene-Neogene systems in the southern Yellow Sea area. [source] Response of the Rhine,Meuse fluvial system to Saalian ice-sheet dynamicsBOREAS, Issue 3 2008FREEK S. BUSSCHERS A new reconstruction of the interaction between the Saalian Drente glaciation ice margin and the Rhine,Meuse fluvial system is presented based on a sedimentary analysis of continuous core material, archived data and a section in an ice-pushed ridge. Optically Stimulated Luminescence (OSL) was applied to obtain independent age control on these sediments and to establish a first absolute chronology for palaeogeographical events prior to and during the glaciation. We identified several Rhine and Meuse river courses that were active before the Drente glaciation (MIS 11-7). The Drente glaciation ice advance into The Netherlands (OSL-dated to fall within MIS 6) led to major re-arrangement of this drainage network. The invading ice sheet overrode existing fluvial morphology and forced the Rhine,Meuse system into a proglacial position. During deglaciation, the Rhine shifted into a basin in the formerly glaciated area, while the Meuse remained south of the former ice limit, a configuration that persisted throughout most of the Eemian and Weichselian periods. An enigmatic high position of proglacial fluvial units and their subsequent dissection during deglaciation by the Meuse may partially be explained by glacio-isostatic rebound of the area, but primarily reflects a phase of high base level related to a temporary proglacial lake in the southern North Sea area, with lake levels approximating modern sea levels. Our reconstruction indicates that full ,opening' of the Dover Strait and lowering of the Southern Bight, enabling interglacial marine exchange between the English Channel and the North Sea, is to be attributed to events during the end of MIS 6. [source] Late Pleistocene glacial and lake history of northwestern RussiaBOREAS, Issue 3 2006EILIV LARSEN Five regionally significant Weichselian glacial events, each separated by terrestrial and marine interstadial conditions, are described from northwestern Russia. The first glacial event took place in the Early Weichselian. An ice sheet centred in the Kara Sea area dammed up a large lake in the Pechora lowland. Water was discharged across a threshold on the Timan Ridge and via an ice-free corridor between the Scandinavian Ice Sheet and the Kara Sea Ice Sheet to the west and north into the Barents Sea. The next glaciation occurred around 75,70 kyr BP after an interstadial episode that lasted c. 15 kyr. A local ice cap developed over the Timan Ridge at the transition to the Middle Weichselian. Shortly after deglaciation of the Timan ice cap, an ice sheet centred in the Barents Sea reached the area. The configuration of this ice sheet suggests that it was confluent with the Scandinavian Ice Sheet. Consequently, around 70,65 kyr BP a huge ice-dammed lake formed in the White Sea basin (the ,White Sea Lake'), only now the outlet across the Timan Ridge discharged water eastward into the Pechora area. The Barents Sea Ice Sheet likely suffered marine down-draw that led to its rapid collapse. The White Sea Lake drained into the Barents Sea, and marine inundation and interstadial conditions followed between 65 and 55 kyr BP. The glaciation that followed was centred in the Kara Sea area around 55,45 kyr BP. Northward directed fluvial runoff in the Arkhangelsk region indicates that the Kara Sea Ice Sheet was independent of the Scandinavian Ice Sheet and that the Barents Sea remained ice free. This glaciation was succeeded by a c. 20-kyr-long ice-free and periglacial period before the Scandinavian Ice Sheet invaded from the west, and joined with the Barents Sea Ice Sheet in the northernmost areas of northwestern Russia. The study area seems to be the only region that was invaded by all three ice sheets during the Weichselian. A general increase in ice-sheet size and the westwards migrating ice-sheet dominance with time was reversed in Middle Weichselian time to an easterly dominated ice-sheet configuration. This sequence of events resulted in a complex lake history with spillways being re-used and ice-dammed lakes appearing at different places along the ice margins at different times. [source] Practical Seakeeping Performance Measures for High Speed Displacement VesselsNAVAL ENGINEERS JOURNAL, Issue 4 2006Dr. Kadir Sariöz The seakeeping performance of high-speed displacement vessels is generally assessed, in a probabilistic manner, by using criteria-based measures of merit. Given a set of seakeeping criteria, these measures, such as the Percentage Time of Operation (PTO) and the Seakeeping Performance Index (SPI), could provide an assessment of the operability of the vessel in a specified sea area. The criteria-based measures are based upon the probability of exceeding specified ship motions in a sea environment particular to the vessel's mission. Given the operational area of the vessel, the percentage of time the vessel operates in a particular sea state can be determined by comparing the predicted motions to the motion limiting criteria. However, because the seakeeping criteria are used in a pass/fail manner, the criteria-based procedures give no credit for reducing motions that do not exceed criteria. This may result in misleading conclusions when the relative seakeeping performance of alternative design concepts is compared. It is shown that criteria-free measures, based upon a normalized summation of critical ship responses for a range of ship speeds and wave headings in a specified sea area, may produce more reliable results when the seakeeping performance of alternative designs are compared. This approach also has the clear advantage of not requiring a set of seakeeping criteria, which is subjective in nature. To demonstrate the effect of typical measures of merit on seakeeping performance assessment, six typical high-speed displacement vessel forms are considered in a comparative analysis. Both the criteria-free and criteria-based measures of merit are employed to compare the seakeeping performance of selected vessels. The results indicate that the choice of seakeeping performance measure of merit depends on the nature of seakeeping analysis and criteria-free measures offer a simple, practical, and realistic assessment in comparative seakeeeping studies. [source] Distribution of the Permian Monodiexodina in Karakorum and Kunlun and its Geological SignificanceACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 2 2009Jianxin YAO Abstract: The Permian fusulinoidean genus Monodiexodina is widely distributed in east Tethys. The genus might be an important indicator for the northern margin of Gondwana in northwestern China, but this is disputed. Monodiexodina -bearing areas can be restored as in either northern or southern middle latitudes with a symmetrical distribution between a high latitudinal, cool/cold water climatic realm and a paleotropical, warm water realm. Permian strata bearing Monodiexodina in Karakorum, Muztag Pear, and Buka Daban Pear of the east Kunlun Mountains can be correlated with each other. Faunal analyses and the stratigraphical position of Monodiexodina -bearing strata indicate that both Karakorum, east Kunlun, and the Pamirs were formed in a cool temperate sea area of the northern hemisphere in middle latitudes during the Permian, rather than at the Gondwana margin. [source] Pelagodictyon Clarke, a newly recorded nanodiatom genus for ChinaJOURNAL OF SYSTEMATICS EVOLUTION, Issue 2 2009Yang LI Abstract Marine nanoplanktonic diatoms have been frequently either underestimated or overlooked in phyto-plankton investigations due to their small size (2,20 ,m), which allows most of them to pass through a regular phytoplankton net of 70-,m pore size. For nanoplanktonic diatom classification, water samples (each 2000 mL) were collected from several representative sea areas of Chinese coast from May 2002 to May 2006. Pelagodictyon Clarke was identified as a newly recorded nanodiatom genus for China under transmission electron microscope (TEM). This genus is characterized by the delicate structure of the valve face. The striae are seen to be formed by ribs with cross-ribs (frets) and the intervening spaces are occupied by polygonal cribra situated much close to the exterior face of the valve. Just one species was found, i.e., P. tenue Clarke. Detailed description of the taxonomic characteristics with TEM photographs of this species and its ecological habitat and distribution are given in this paper. Morphological characteristics comparisons among several resembling genera were discussed. [source] Limited-area ensemble predictions at the Norwegian Meteorological InstituteTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 621 2006Inger-Lise Frogner Abstract This study aims at improving 0,3 day probabilistic forecasts of precipitation events in Norway. For this purpose a limited-area ensemble prediction system (LAMEPS) is tested. The horizontal resolution of LAMEPS is 28 km, and there are 31 levels in the vertical. The state variables provided as initial and lateral boundary conditions for the limited-area forecasts are perturbed using a dedicated version of the European Centre for Medium-Range Weather Forecasts (ECMWF) global ensemble prediction system, TEPS. These are constructed by combining initial and evolved singular vectors that at final time (48 h) are targeted to maximize the total energy in a domain containing northern Europe and adjacent sea areas. The resolution of TEPS is T255 with 40 levels. The test period includes 45 cases with 21 ensemble members in each case. We focus on 24 h accumulated precipitation rates with special emphasis on intense events. We also investigate a combination of TEPS and LAMEPS resulting in a system (NORLAMEPS) with 42 ensemble members. NORLAMEPS is compared with the 21-member LAMEPS and TEPS as well as the regular 51-member EPS run at ECMWF. The benefit of using targeted singular vectors is seen by comparing the 21-member TEPS with the 51-member operational EPS, as TEPS has considerably larger spread between ensemble members. For other measures, such as Brier Skill Score (BSS) and Relative Operating Characteristic (ROC) curves, the scores of the two systems are for most cases comparable, despite the difference in ensemble size. NORLAMEPS has the largest ensemble spread of all four ensemble systems studied in this paper, while EPS has the smallest spread. Nevertheless, EPS has higher BSS with NORLAMEPS approaching for the highest precipitation thresholds. For the area under the ROC curve, NORLAMEPS is comparable with or better than EPS for medium to large thresholds. Copyright © 2006 Royal Meteorological Society [source] Effects of shear sheltering in a stable atmospheric boundary layer with strong shearTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 596 2004Ann-Sofi Smedman Abstract Data from two marine field experiments in the Baltic Sea with stable stratification have been analysed. The purpose was to test the concept of the ,detached' or ,top-down' eddies and the ,shear-sheltering' mechanism in the presence of a low-level wind speed maximum in the atmosphere. Data used include turbulence and profile measurements on two 30 m towers and concurrent wind profiles throughout the boundary layer obtained from pilot-balloon soundings. Measurements show that large eddies are being suppressed when there is a low-level wind speed maximum present somewhere in the layer 40,300 m above the water surface and when the stratification is slightly stable. The effect is seen both in normalized standard deviations of the velocity components and in corresponding component spectra. In previous work it was argued that the relatively large eddies, which dominate the low wave number spectra in measurements in the surface layer, are detached or top-down eddies generated higher up in the boundary layer, that interact with the surface layer. The low-level wind maximum introduces a distinct layer with strong vorticity which, according to the shear-sheltering hypothesis, prevents these eddies from penetrating downwards. In the limit of the wind maximum occurring at a very low height (less than about 100 m), usual turbulence statistics characteristic of the ,canonical' boundary layer are found. Combining all the statistics, it is demonstrated that the wavelength of maximum spectral energy is locally related to a turbulence length-scale, which shows that for values of the Richardson number of unity or less the effect of the local wind gradient is greater than that of static stability. The reduction of length-scale with the strength of a low-level wind maximum, explains the observed reduction (by a factor of two) of the turbulent flux of sensible heat at the surface. This result indicates that the shear-sheltering mechanism is likely to play an important role in the turbulent exchange process at the surface in sea areas where low-level wind maxima are a frequently occurring phenomenon, such as the Baltic and other large water bodies surrounded by landmasses. Copyright © 2004 Royal Meteorological Society [source] | ||||||||||||||||