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991.
Zavialov P. O. Zavialov I. B. Izhitskiy A. S. Izhitskaya E. S. Konovalov B. V. Krementskiy V. V. Nemirovskaya I. A. Chasovnikov V. K. 《Oceanology》2022,62(2):162-170
Oceanology - The paper presents the results of an analysis of the main pollutants (heavy metals, pesticides, detergents, hydrocarbons) in water, suspended particulate matter, and bottom sediments,... 相似文献
992.
Pockmarks in the inner Oslofjord,Norway 总被引:2,自引:3,他引:2
Multibeam bathymetric surveys of the Inner Oslofjord, Norway have revealed a high density of pockmarks in the 179-km2 inner fjord area, which contains over 500 pockmarks of varying size, typically 20–50 m in diameter and 2–10 m deep. These
pockmarks have been investigated with a variety of techniques, including acoustic subbottom profiling, sedimentological and
geochemical analyses of cores, remotely operated vehicle observation, and morphometry. Both the distribution and shapes of
the pockmarks suggest that they are related to structures in the bedrock underlying relatively thin (<50 m) unconsolidated
glacial and postglacial sediments. The data provide no direct indication of a particular mode of pockmark formation, but release
of large amounts of biogenic, shallow methane seems unlikely. Several lines of evidence point to a continuous process of pockmark
formation followed by inactivity, with some pockmarks recently active whereas others have been inactive for a considerable
time. Some pockmarks are characterised by coarse sediment in their centres. The density, variety and easy access make this
pockmark field an ideal model area for pockmark research.
John S. Gray is deceased. 相似文献
993.
This paper documents a new method for describing channel-related sedimentary deposits based on formal language theory. Using this method an analogue model of a sedimentary deposit can be encoded as a grammar. A program, called a parser, has been developed which can generate stochastic maps of these sedimentary deposits based on information in a specified grammar. The maps of sedimentary deposits generated by the parser have the same type, spatial arrangement, shape and size distribution as the analogue model. The successful generation of depositional maps represents a crucial step in the ongoing development of a new technique designed to generate 3D static geological models of sedimentary successions. The maps can be conditioned to match sparse hard data in the form of channel segments interpreted from seismic horizon maps. 相似文献
994.
Taro Takahashi Stewart C. Sutherland Rik Wanninkhof Colm Sweeney Richard A. Feely David W. Chipman Burke Hales Gernot Friederich Francisco Chavez Christopher Sabine Andrew Watson Dorothee C.E. Bakker Ute Schuster Nicolas Metzl Hisayuki Yoshikawa-Inoue Masao Ishii Takashi Midorikawa Yukihiro Nojiri Arne Krtzinger Tobias Steinhoff Mario Hoppema Jon Olafsson Thorarinn S. Arnarson Bronte Tilbrook Truls Johannessen Are Olsen Richard Bellerby C.S. Wong Bruno Delille N.R. Bates Hein J.W. de Baar 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):2075-2076
995.
Benjamin C. Green David J. Smith Sarah E. Earley Leanne J. Hepburn Graham J.C. Underwood 《Estuarine, Coastal and Shelf Science》2009,85(2):247-256
European intertidal salt marshes are important nursery sites for juvenile fish and crustaceans. Due to the increasing threat of habitat loss, the seasonal changes of salt marsh fish communities need to be understood in order to appreciate the ecological and economic importance of the saltmarsh habitat. This study was the first in Great Britain to investigate the seasonal changes of salt marsh fish communities and the variation in community structure between closely located marsh habitats. Between February 2007 and March 2008, five marshes on three estuaries of the Essex coastline were sampled using flume nets to block off intertidal creeks at high tide. Fourteen fish species were caught. The community overall was dominated by three species that made up 91.6% of the total catch: the common goby Pomatoschistus microps (46.2% of the total catch), juvenile herring Clupea harengus (24.3%), and juvenile and larval sea bass Dicentrarchus labrax (21.2%). Cluster analysis demonstrated clear seasonal patterns, with some community structures unique to specific marshes or estuaries. The marsh fish community shifts from a highly diverse community during spring, to a community dominated by D. labrax and P. microps in autumn, and low diversity during winter months. Gravimetric stomach content analysis of fish community identified three main trophic guilds; macroinvertivores, planktivores and omnivores. The macroinvertivore feeding guild contained D. labrax and P. microps, the two most frequently occurring species. This investigation demonstrates the importance of British salt marshes as nursery habitats for commercial fish species. 相似文献
996.
The data of beam propagation of internal waves into the ocean are confirmed by several analytical solutions of the linear
long wave theory. The obtained solutions are applied to calculate the mode of the internal waves. 相似文献
997.
K. E. Muryshev A. V. Eliseev I. I. Mokhov N. A. Diansky 《Izvestiya Atmospheric and Oceanic Physics》2009,45(4):416-433
A new version of the Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS), climate model (CM) has been
developed using an ocean general circulation model instead of the statistical-dynamical ocean model applied in the previous
version. The spatial resolution of the new ocean model is 3° in latitude and 5° in longitude, with 25 unevenly spaced vertical
levels. In the previous version of the oceanic model, as in the atmospheric model, the horizontal resolution was 4.5° in latitude
and 6° in longitude, with four vertical levels (the upper quasi-homogeneous layer, seasonal thermocline, abyssal ocean, and
bottom friction layer). There is no correction for the heat and momentum fluxes between the atmosphere and ocean in the new
version of the IAP RAS CM. Numerical experiments with the IAP RAS CM have been performed under current initial and boundary
conditions, as well as with an increasing concentration of atmospheric carbon dioxide. The main simulated atmospheric and
oceanic fields agree quite well with observational data. The new version’s equilibrium temperature sensitivity to atmospheric
CO2 doubling was found to be 2.9 K. This value lies in the mid-range of estimates (2–4.5 K) obtained from simulations with state-of-the-art
models of different complexities. 相似文献
998.
We analyze the statistical structure of the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll in the northwest part of the Black Sea with an aim to apply the method of optimal interpolation to the restoration
of the maps of these fields according to the restricted amounts of data. We determine the scales of smoothing for the selection
of the random components of the fields and estimate their difference from the statistical model uniform and isotropic over
the space correlation coefficients. The functions of spectral densities are constructed along various sections and the best
intervals of discretization of the fields required to perform the optimal interpolation with given accuracy are determined.
It is shown that the construction of the maps of fields under the conditions of controlled accuracy of reconstruction of their
values remains possible even if the amounts of the input satellite data are significantly decreased. We consider a procedure
of evaluation of the best possible amounts of data required for the use of the method of optimal interpolation. Some examples
of application of this procedure to the data of remote sensing of the fields of surface temperature and the concentration
of chlorophyll are presented. 相似文献
999.
P.S. Loh A.D. Reeves S.M. Harvey J. Overnell A.E.J. Miller 《Estuarine, Coastal and Shelf Science》2008
Sea lochs are zones of rapid organic matter (OM) turnover. Most of this OM is of allochthonous origin, being introduced into the lochs via freshwater input. In this study the behaviour of terrestrially derived OM was elucidated using a combination of parameters which indicate OM diagenesis in the near surface sediments from two Scottish sea lochs, Loch Creran and Loch Etive. Alkaline CuO oxidation was used to determine lignin phenols which serve as biomarkers for terrestrial OM in sediments. Stable carbon isotope, total carbon and nitrogen and total OM (including the labile and refractory fractions) compositions were also determined. 相似文献
1000.
P.P. Povinec J. de Oliveira E.S. Braga J.-F. Comanducci J. Gastaud M. Groening I. Levy-Palomo U. Morgenstern Z. Top 《Estuarine, Coastal and Shelf Science》2008
Stable isotopes, tritium, radium isotopes, radon, trace elements and nutrients data were collected during two sampling campaigns in the Ubatuba coastal area (south-eastern Brazil) with the aim of investigating submarine groundwater discharge (SGD) in the region. The isotopic composition (δD, δ18O, 3H) of submarine waters was characterised by significant variability and heavy isotope enrichment. The stable isotopes and tritium data showed good separation of groundwater and seawater groups. The contribution of groundwater in submarine waters varied from a few % to 17%. Spatial distribution of 222Rn activity concentration in surface seawater revealed changes between 50 and 200 Bq m−3 which were in opposite relationship with observed salinities. Time series measurements of 222Rn activity concentration in Flamengo Bay (from 1 to 5 kBq m−3), obtained by in situ underwater gamma-spectrometry showed a negative correlation between the 222Rn activity concentration and tide/salinity. This may be caused by sea level changes as tide effects induce variations of hydraulic gradients, which increase 222Rn concentration during lower sea level, and opposite, during high tides where the 222Rn activity concentration is smaller. The estimated SGD fluxes varied during 22–26 November between 8 and 40 cm d−1, with an average value of 21 cm d−1 (the unit is cm3/cm2 per day). The radium isotopes and nutrient data showed scattered distributions with offshore distance and salinity, which implies that in a complex coast with many small bays and islands, the area has been influenced by local currents and groundwater–seawater mixing. SGD in the Ubatuba area is fed by coastal contaminated groundwater and re-circulated seawater (with small admixtures of groundwater), which claims for potential environmental concern with implications on the management of freshwater resources in the region. 相似文献