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41.
During a cruise of r/v ‘Oceania’ in May 2006, seven vertical dissolved organic carbon (DOC) concentration profiles were produced against a background of CTD, chlorophyll a (chl a) and phaeopigment concentration profiles. The results indicate distinct vertical and spatial DOC fluctuations, ranging from 248 ± 7 μmol C dm−3 at 70 m depth at the westernmost station G/06 to 398 ± 5 μmol C dm−3 at 5 m depth at station A/06 in the western Gulf of Gdańsk. DOC concentrations were the highest at 10 m depth, where phytoplankton activity was relatively intensive, as reflected by the active chl a concentration distribution. DOC concentrations decreased towards the sea bottom.  相似文献   
42.
The variability of two modes of Labrador Sea Water (LSW) (upper and deep Labrador Sea Water) and their respective spreading in the interior North Atlantic Ocean are investigated by means of repeated ship surveys carried out along the zonal WOCE line A2/AR19 located at 43–48°N (1993–2007) and along the GOOS line at about 48–51°N (1997–2002). Hydrographic section data are complemented by temperature, salinity, and velocity time series recorded by two moorings. They have been deployed at the western flank of the Mid-Atlantic Ridge (MAR) in the Newfoundland Basin during 1996–2004. The analysis of hydrographic anomalies at various longitudes points to a gradual eastward propagation of LSW-related signals, which happens on time scales of 3–6 years from the formation region towards the MAR. Interactions of the North Atlantic Current (NAC) with the Deep Western Boundary Current (DWBC) close to Flemish Cap point to the NAC being the main distributor of the different types of LSW into the interior of the Newfoundland Basin. Comparisons between the ship data and the mooring records revealed that the mooring sites are located in a region affected by highly variable flow. The mooring time series demonstrate an elevated level of variability with eddy activity and variability associated with the NAC considerably influencing the LSW signals in this region. Hydrographic data taken from Argo profiles from the vicinity of the mooring sites turned out to mimic quite well the temporal evolution captured by the moorings. There is some indication of occasional southward flow in the LSW layer near the MAR. If this can be considered as a hint to an interior LSW-route, it is at least of minor importance in comparison to the DWBC. It acts as an important supplier for the interior North Atlantic, distributing older and recently formed LSW modes southward along the MAR.  相似文献   
43.
In late 1980s, a dense network of deep capillary burrows was reported on the Vøring Plateau, Nordic Seas, and associated with a sipunculan belonging to the genus Nephasoma. This sipunculan was responsible for rapid transport of organic matter from the sediment surface down a deep burrow network. Over 460 specimens belonging to the genus Nephasoma were collected from the deep Nordic Seas during four cruises from 2000–2005 and four species identified: Nephasoma abyssorum abyssorum, N. diaphanes diaphanes, N. diaphanes corrugatum and N. lilljeborgi. The species responsible for the deep burrows and rapid subduction of organic matter can now be confirmed as Nephasoma lilljeborgi. Deep burrows associated with N. lilljeborgi were observed on the Vøring Plateau, Bear Island Fan, Svalbard Margin and Yermak Plateau and may be a seabed feature endemic to the Nordic Seas region. N. lilljeborgi could have a significant role in influencing the ecology and geochemistry of the Nordic Seas region. It is recommended that future benthic community studies in the Nordic Seas region confirm the species identity of sipunculan specimens in order to determine the ecological and geochemical importance of the specimens.  相似文献   
44.
We conducted acoustical surveys with a horizontal beam transducer to detect fish and with a vertical beam transducer to detect depth and macrophytes in two typical shallow lakes along the middle and lower reaches of the Changjiang(Yangtze) River in November 2013. Both lakes are subject to active fish management with annual stocking and removal of large fish. The purpose of the study was to compare hydroacoustic horizontal beam estimates with fish landings. The preliminary results show that the fish distribution patterns dif fered in the two lakes and were af fected by water depth and macrophyte coverage. The hydroacoustically estimated fish biomass matched the commercial catch very well in Niushan Lake, but it was two times higher in Kuilei Lake. However, acoustic estimates included all fish, whereas the catch included only fish 45 cm(smaller ones were released). We were unable to determine the proper regression between acoustic target strength and fish length for the dominant fish species in the two lakes.  相似文献   
45.
46.
Width of the first ray of the pectoral fin has been measured in two places for 154 young and 89 adult wels. Statistical relationships between the above characters and fish length as well as its maturity and sex have been proved. Three models of discriminant function for identification of adult fish sex have been derived and verified. The accuracy of sex separation has been 89,5% in a standard sample of wels, and 90,6% in a routine sample, after an adjustment in the procedure.  相似文献   
47.
Summary The western part of the Baltic Sea is a shallow transition area which is characterized by the water exchange between the Baltic and the North Sea. The dynamic processes in this area are forced by sea-level differences between the North Sea and Baltic Sea as well as by local wind and freshwater input. The response patterns are modified by Earth's rotation, bathymetric structures and the alignment of the coast. Series of satellite images permit synoptical views of these pattern and their temporal and spatial development.Sea surface temperature maps derived from infrared data supplied by the National Oceanic and Atmospheric Administration (NOAA) satellite-borne Advanced Very High Resolution Radiometer (AVHRR) are used to show various features like upwelling filaments and eddies.The River Oder discharges into the Pomeranian Bight is the main source of freshwater input into the western Baltic. The variability of this inflow and of the affected coastal seas is being presented in relation to the prevailing meteorological conditions.
Dynamische Besonderheiten in der westlichen Ostsee untersucht anhand von NOAA-AVHRR-Daten
Zusammenfassung Die westliche Ostsee ist ein flaches Übergangsgebiet, das durch den Wasseraustausch zwischen Nord- und Ostsee charakterisiert ist. Die dynamischen Prozesse werden in diesem Gebiet durch Wasserstandsdifferenzen zwischen Nord- und Ostsee, durch den lokalen Wind und die Süßwasserzufuhr getrieben. Die Reaktionsmuster werden modifiziert durch die Erdrotation, die Bathymetrie und den Küstenverlauf.Serien von Satellitendaten gestatten die synoptische Betrachtung dieser Muster und ihrer zeitlichen und räumlichen Entwicklung.Karten der Wasseroberflächentemperatur (SST), abgeleitet aus Infrarotdaten des Advanced Very High Resolution Radiometer (AVHRR), werden genutzt, um verschiedene Strukturen wie Auftrieb, Filamente und Wirbel zu präsentieren. Das Radiometer wird durch die National Oceanic and Atmospheric Administration (NOAA) auf Wettersatelliten betrieben.Der Flußeintrag der Oder in die Pommersche Bucht ist die bedeutendste Süßwasserzufuhr in die westliche Ostsee. Die Veränderlichkeit des Einstroms und die beeinflußten Gebiete sind in Abhängigkeit von den meteorologischen Bedingungen dargestellt.

Recherche du caractéristiques dynamiques en mer Baltique ouest á l'aide de données NOAA-AVHRR
Résumé La partie ouest de la mer Baltique est une zone de transition de profondeur réduite, caractérisée par un échange des eaux entre la mer du Nord et la mer Baltique.Dans cette zone, les processus dynamiques proviennent des différences de niveau de la mer du Nord et de la mer Baltique, des vents locaux et de l'apport en eau douce. Les modèles créés sont modifiés à partir de la rotation terrestre, de la bathymétrie et de la morphologie côtière.Les données satellite permettent d'établir une étude synoptique de ces processus dans l'ensemble de la zone ainsi que leur développement spatio-temporel au moyen de séries.Des cartes de température superficielle (SST) obtenues à partir des données radiométriques infrarouges AVHRR (Advanced Very High Resolution Radiometer) sont utilisées pour présenter des exemples SST caractéristiques de résultats de processus dynamiques de l'ouest de la mer Baltique. Les données radiométriques proviennent du National Oceanic and Atmospheric Administration (NOAA) à partir de satellites météorologiques.La dépendance des développements spatio-temporels de modèles en fonction des conditions météorologiques est discutée à partir de scènes et de séries particulières.Des exemples d'upwelling devant les côtes allemandes, suédoises et polonaises ainsi que des fronts, des filaments et des tourbillons sont présentés.La plus grande partie de l'apport en eau douce à l'ouest de la mer Baltique provient du fleuve Oder, en baie de Poméranie. L'influence des facteurs météorologiques sur la variation de ce déversement et sur les zones influencées est présentée.
  相似文献   
48.
49.
Polarized infrared absorption spectra of thin single-crystal slabs parallel to (010) and (001) of a staurolite from Pizzo Forno, Ticino, with analyzed composition (Fe2.9Mg0.9Zn0.1Mn0.1)Al17.5Ti0.1(Si7.7Al0.3)O48H3 have been measured in the range of 3000–4000 cm?1. From the pleochroitic behaviour of the OH-vibrations three groups of bands can be distinguished: the bands of group I, a strong band at 3445 cm?1 plus a weak shoulder at 3358 cm?1, and the bands of group II, a weak band centered at 3677 cm?1 plus a shoulder at 3635 cm?1, are assigned to the H1 and H2 protons, respectively. The bands of group III, a weak band at 3577 cm?1 plus a shoulder, cannot be interpreted on the basis of the proton positions known so far. We assign them to an additional proton H3, which is bonded to O1 and shows a bifurcated hydrogen bridge to two O5 in a vacant T2 site.  相似文献   
50.
The hydrodynamics of saline water in Polish estuaries are addressed in this paper. The phenomena are described on the basis of field data from several types of estuaries along the Polish Baltic Coast. Field measurements were made to reveal and to characterize the physical processes in these estuaries; this information was then used for analytic testing and verification of mathematical models. The results demonstrate the unsteady and changeable nature of both the flow conditions and the motion of salt water in tideless estuaries. The magnitudes and directions of the barotropic and baroclinic horizontal pressure gradients have a marked influence on the flow characteristics and motion of salt water in these tideless estuaries.  相似文献   
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