Oceanologica Acta最新文献_第8页

Environmental control of mesozooplankton community structure in the Seine estuary (English Channel) 塞纳河河口(英吉利海峡)中浮游动物群落结构的环境控制

Oceanologica Acta Pub Date : 2002-01-01 DOI: 10.1016/S0399-1784(01)01177-X

Pascal Mouny, Jean-Claude Dauvin

{"title":"Environmental control of mesozooplankton community structure in the Seine estuary (English Channel)","authors":"Pascal Mouny, Jean-Claude Dauvin","doi":"10.1016/S0399-1784(01)01177-X","DOIUrl":"10.1016/S0399-1784(01)01177-X","url":null,"abstract":"<div>This paper is the first to describe the spatio-temporal changes of mesozooplankton in the Seine estuary. Monthly samples were collected along the estuary in 1996 in order to analyse the seasonal changes of the mesozooplankton community and to identify the major environmental parameters that may influence the spatial distribution of zooplankton in this megatidal estuary. Statistical analysis (canonical correspondence analysis) showed that salinity was the main factor correlated with the longitudinal distribution of zooplankton. Marine species (Temora longicornis, barnacle larvae…) were located in the outer part of the estuary, while more oligohaline species (Eurytemora affinis) were recorded in the inner part of the estuary. A mixed zone was characterised by the presence of the neritic copepods Acartia spp. and Eurytemora affinis. The marine species (e.g. T. longicornis, Oikopleura dioica, Barnacle larvae) showed maximum abundance at the end of spring (June) while the most abundant estuarine species, E. affinis, peaked in late winter-spring and declined with the onset of summer. This copepod dominated the estuarine zooplankton throughout the year, and found in the Seine estuary very high favourable conditions to exhibit ultimate abundances (> 190 000 ind m–3) which is one order of magnitude higher than those found in other European estuaries. It represented the main prey for major planktonivorous species such as suprabenthic and fish species located living in the upstream zone of the Seine estuary.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"25 1","pages":"Pages 13-22"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01177-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75652488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 116

Temporal variability in the biochemical composition of sedimentary organic matter in an intertidal flat of the Galician coast (NW Spain) 西班牙西北部加利西亚海岸潮间带沉积有机质生化组成的时间变异性

Oceanologica Acta Pub Date : 2002-01-01 DOI: 10.1016/S0399-1784(01)01178-1

Sira Cividanes, Mónica Incera, Jesús López

{"title":"Temporal variability in the biochemical composition of sedimentary organic matter in an intertidal flat of the Galician coast (NW Spain)","authors":"Sira Cividanes, Mónica Incera, Jesús López","doi":"10.1016/S0399-1784(01)01178-1","DOIUrl":"10.1016/S0399-1784(01)01178-1","url":null,"abstract":"<div>Temporal variations and spatial distribution of sedimentary organic matter composition were investigated over a one year period in an intertidal flat of the NW Spain. Sediment samples were collected from 0 to 25 cm depth, every three months, from January 1997 to January 1998 at three tidal levels (high, medium and low). Changes in the elemental and biochemical composition were assessed to gather information on temporal and spatial fluctuations in quantity and quality of sedimentary organic matter potentially available to benthic deposit-feeder nutrition. Organic matter content was significantly higher at the medium tidal level, while minimum values were found at the high tidal level. The different biochemical classes of organic compounds exhibited different temporal patterns. Carbohydrate and lipid concentrations decreased with sediment depth. The biopolymeric fraction of organic carbon (i.e. the sum of lipid, carbohydrate and protein carbon) was dominated by proteins (61%), followed by lipids (26%) and carbohydrates (14%). Biopolymeric carbon accounted for only a small fraction (37% on average) of the total organic carbon. Refractory organic carbon (i.e. non biopolymeric) accounted for 50 to 80% of the total organic carbon and it tended to be buried into deeper sediment layers. The nutritional quality of the sedimentary organic matter, expressed as the biopolymeric carbon to total organic carbon ratio, was higher in January 1997, when also the higher protein to carbohydrate ratio values were observed and related to the presence of newly-produced organic matter. Low biopolymeric carbon to total organic carbon ratio and protein to carbohydrate ratio were recorded during the rest of the year, indicating a low-quality and aged organic matter. Results of the present study revealed an inverse relationship between the overall amount of organic matter and its potential availability to consumers.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"25 1","pages":"Pages 1-12"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01178-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"96635965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 93

Causes of long-term changes in Aegean sea deep water 爱琴海深水长期变化的原因

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01172-0

Roberta Boscolo , Harry Bryden

{"title":"Causes of long-term changes in Aegean sea deep water","authors":"Roberta Boscolo , Harry Bryden","doi":"10.1016/S0399-1784(01)01172-0","DOIUrl":"10.1016/S0399-1784(01)01172-0","url":null,"abstract":"<div>Recent observations of newly formed deep water in the Aegean sea prompts this analysis of whether such deep water could be formed locally by the combination of an increase in net evaporation and wintertime water mass transformation. River diversion projects in Russia and Egypt since the 1950s have effectively increased the amount of net evaporation over the eastern Mediterranean basin. Historical profiles show that low salinity intermediate waters separated the deep and upper waters in the Aegean in 1961–1962. Within a simple mixed layer model, imposing a small net evaporation of 10 cm·yr–1 on the observed hydrographic conditions in March 1962 results in the gradual erosion of the low salinity intermediate waters. After 25 years, the low salinity intermediate waters are absent in agreement with observations made in September 1987. Continuing to force the model with the small net evaporation and with monthly heat and freshwater exchange anomalies from March 1987, new deep water could have been formed as early as March 1988. In the model, major deep water formation events occurred during the severe winters of 1991–1992 and 1992–1993 resulting in the formation of saltier and notably colder deep waters. The effective increase in net evaporation slowly increases the salinity and decreases the stratification in the Aegean sea until a severe winter leads to deep convection and new bottom water formation.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 519-527"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01172-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73196820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27

Assessment of viability in the bacterial standing stock of the Antarctic sea from the Indian side 从印度一侧评估南极海域细菌存量的生存能力

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01170-7

Ponnapakam A Loka Bharathi, Shanta Nair, Maria-Judith B.D De Souza, Dorairajsingham Chandramohan

{"title":"Assessment of viability in the bacterial standing stock of the Antarctic sea from the Indian side","authors":"Ponnapakam A Loka Bharathi, Shanta Nair, Maria-Judith B.D De Souza, Dorairajsingham Chandramohan","doi":"10.1016/S0399-1784(01)01170-7","DOIUrl":"10.1016/S0399-1784(01)01170-7","url":null,"abstract":"<div>During the austral summer, we examined the bacterial population along the cruise track extending from 70° S and 18° E to 30° S and 35° E. During the cruise, three distinct fractions of the bacterioplankton viz. total count, total direct viable and retrievable counts were simultaneously enumerated in these waters. In the stations south of the convergent region designated as section I the population ranged within 108–9 L–1 whereas in the north of the region designated as section II they were one order higher and ranged from 109–10 L–1. The percentage of viability in the region was high corresponding to the generally high chlorophyll and primary productivity encountered in the eastern Aghulas bank. The study substantiates the hypothesis that in the Antarctic, not only the bacterial standing stock but also the active population of bacterioplankton (ca. 50 %) are almost equal in abundance to those in the other oceanic or coastal regions. The viable fraction forms a hitherto unreported significant component of these waters.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 577-580"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01170-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88955307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

The penetration of the Northern Current over the Gulf of Lions (Mediterranean) as a downscaling problem 北流在狮子湾(地中海)的渗透是一个降尺度问题

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01166-5

Francis Auclair, Patrick Marsaleix, Claude Estournel

{"title":"The penetration of the Northern Current over the Gulf of Lions (Mediterranean) as a downscaling problem","authors":"Francis Auclair, Patrick Marsaleix, Claude Estournel","doi":"10.1016/S0399-1784(01)01166-5","DOIUrl":"10.1016/S0399-1784(01)01166-5","url":null,"abstract":"<div>Coastal shelf models suffer from the difficulty of specifying both the initial field and the external circulation at the open boundary. Only basin scale models can have the right space-time variability to routinely provide such information. De facto, such models have however a coarser resolution than the coastal model and the downscaling of the circulation to the high resolution grid is biased. Indeed the models are not necessarily based on the same physics and the interactions of the general circulation with the topography, in particular over the shelf break region, are generally not correctly represented on the large-scale grid. Studying the response of the Northern Current to the atmospheric forcing in the region of Marseille (France) and its interactions with the continental shelf break, we evaluate in this paper the spurious consequences at short and medium range that can result from a crude interpolation of basin scale model outputs to initialize and force along its open boundaries a high resolution coastal model. We show how an analysis of these fields based on a 3D variational initialization technique can improve the results.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 529-544"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01166-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"56208732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 40

Observation of irregular wave transformation in the surf zone over a gently sloping sandy beach on the French Atlantic coastline 法属大西洋沿岸缓坡沙滩上冲浪带不规则波浪变换的观测

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01171-9

Nadia Sénéchal, Hélène Dupuis, Philippe Bonneton, Hélène Howa, Rodrigo Pedreros

{"title":"Observation of irregular wave transformation in the surf zone over a gently sloping sandy beach on the French Atlantic coastline","authors":"Nadia Sénéchal, Hélène Dupuis, Philippe Bonneton, Hélène Howa, Rodrigo Pedreros","doi":"10.1016/S0399-1784(01)01171-9","DOIUrl":"10.1016/S0399-1784(01)01171-9","url":null,"abstract":"<div>The dissipation of the sea-swell frequency band energy (nominally 0.09 < f ≤ 0.3 Hz) and the distribution of low frequency band energy (nominally 0.005 ≤ f ≤ 0.09 Hz) on a transect crossing the surf and swash zones of a fine grained, gently sloping barred beach are investigated with data from a five element synchronous pressure sensor line deployed for 8 d. In this paper, we suggest a rational method to determine the frequency cut-off between the low frequency band and the sea-swell frequency band from the cross-shore evolution of the sea surface elevation energy density spectra. Sea-swell wave heights are depth limited, consistent with previous works whereas low frequency wave heights are independent of the local water depth. In models of surf zone hydrodynamics, wave energy dissipation is often parameterized in terms of γ, the ratio of the sea-swell significant wave height to the local mean water depth. The observed values of γ are well correlated with β/kh (where β is the beach slope, h the mean water depth and k the local wavenumber corresponding to the local centroidal frequency and depth) but the linear regression through the data differs significantly from previous work. Finally, the evolution of the energy distribution in both frequency band indicates the local (not only dependent on the depth) behaviour of two phenomena: the phenomenon of merging shocks and the distribution of low frequency band into two components – principally infragravity motions (0.005 ≤ f < 0.05 Hz) or first subharmonic motions (0.05 ≤ f < 0.09 Hz).</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 545-556"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01171-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"102184338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 55

Seasonal and interannual changes in Intense Benguela Upwelling (1982–1999) 强烈本格拉上升流的季节和年际变化(1982-1999年)

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01173-2

Eberhard Hagen , Rainer Feistel , Jacobus J Agenbag , Thomas Ohde

{"title":"Seasonal and interannual changes in Intense Benguela Upwelling (1982–1999)","authors":"Eberhard Hagen , Rainer Feistel , Jacobus J Agenbag , Thomas Ohde","doi":"10.1016/S0399-1784(01)01173-2","DOIUrl":"10.1016/S0399-1784(01)01173-2","url":null,"abstract":"<div>Monthly maps of remotely sensed sea surface temperatures derived from NOAA/AVHRR thermal images are used to describe changes in ‘Intense Benguela Upwelling’ during 1982–1999. The coastal area under investigation lies between 9–34° S and 8–20° E and the total area of cold water between the coast and the course of the 13 °C isotherm is considered to be an index of intense, active upwelling. It exhibits a decreasing trend over the study period of 18 years and some evidence for a quasi-cycle of about 27 months. Seasonal cycles are discussed for the total cold water area as well as for its mean alongshore and offshore extents. The main season of cold surface water was found to occur between July and September during the austral winter. It peaks in August with a mean area of about 30×103 km2 and relaxes drastically during the rest of the year. The underlying process of intense coastal upwelling is regionally trapped in two coastal zones. These are centred around 26 and 29° S and reach a mean offshore extension of 210 and 130 km, respectively, to form giant upwelling filaments. The area of cold water drastically shrinks, roughly by a factor of two, during weak upwelling years but significantly expands by a factor of about 1.5 during strong years. Associated sea level changes along the south-west African coast were derived from measurements at four coastal stations between 23 and 34° S during 1982–1987. The first principal component describes about 63 % of the total sea level variance. The lowest sea levels were found in the prominent Lüderitz cell near 26° S. On both the annual and interannual time scale, decreasing cold water areas are accompanied by increasing sea levels and vice versa. Mean seasonal cycles reveal that variations in the total cold water area lag behind those in the sea level along the entire south-west African coast by about 1 month.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 557-568"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01173-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75482155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 68

Role of biotic interactions on seasonal migrations of the macrozoobenthos living in the upper tidal-flat of the Mont-Saint-Michel bay, France 生物相互作用对法国圣米歇尔山潮滩大型底栖动物季节性迁徙的影响

Oceanologica Acta Pub Date : 2001-11-01 DOI: 10.1016/S0399-1784(01)01165-3

Tarik Meziane , Christian Retière

{"title":"Role of biotic interactions on seasonal migrations of the macrozoobenthos living in the upper tidal-flat of the Mont-Saint-Michel bay, France","authors":"Tarik Meziane , Christian Retière","doi":"10.1016/S0399-1784(01)01165-3","DOIUrl":"10.1016/S0399-1784(01)01165-3","url":null,"abstract":"<div>On the tidal flat of the western part of the Mont-Saint-Michel bay, the macrozoobenthos of the upper flat is characterised by an assemblage of the Macoma balthica community. The dominant species are M. balthica, Nereis diversicolor and Corophium volutator. A field monitoring during a 1-year period along a four-stations transect perpendicularly to the shore showed that biotic interactions affected the local distributions of these species. This was particularly obvious from late spring to late summer while, because of the density increases, competitions for space and/or resources were induced, which stimulated migrations. Intra-specific competition seemed to induce the migration of the 1-year-old M. balthica. Consequently, the migration of the young bivalves from the level where this species is dominant to upper levels stimulated the migration of C. volutator population. This migration had a negative effect on the abundance of the amphipods. The migration of N. diversicolor during the end of the summer population to the lower levels of the tidal flat seemed to prevent the return of the C. volutator population to their original before-migration area, even though M. balthica density decreased.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 6","pages":"Pages 569-575"},"PeriodicalIF":0.0,"publicationDate":"2001-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01165-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91433357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

A non-linear second-order stochastic model of ocean surface waves 海洋表面波的非线性二阶随机模型

Oceanologica Acta Pub Date : 2001-09-01 DOI: 10.1016/S0399-1784(01)01164-1

Maminirina Joelson, Alfred Ramamonjiarisoa

引用次数: 1

Numerical study of sedimentary impact of a storm on a sand beach simulated by hydrodynamic and sedimentary models 用水动力和沉积模式模拟风暴对沙滩的沉积影响的数值研究

Oceanologica Acta Pub Date : 2001-09-01 DOI: 10.1016/S0399-1784(01)01168-9

Samuel Meulé , Christel Pinazo , Claude Degiovanni , Jean-Paul Barusseau , Maurice Libes

{"title":"Numerical study of sedimentary impact of a storm on a sand beach simulated by hydrodynamic and sedimentary models","authors":"Samuel Meulé , Christel Pinazo , Claude Degiovanni , Jean-Paul Barusseau , Maurice Libes","doi":"10.1016/S0399-1784(01)01168-9","DOIUrl":"10.1016/S0399-1784(01)01168-9","url":null,"abstract":"<div>In marine coastal environments, storms have a major morphological impact on sand beaches. This study, part of the French Programme National d’Environnement Côtier, consisted in developing and applying hydrodynamic and sedimentary models to simulate the major processes that modify sand beaches. In order to study sediment dynamics, we developed three models to simulate waves, currents and sediment transport associated with a storm event. The wave model was a Mild Slope Equation model based on the parabolic approximation of the refraction-diffraction equation of Berkhoff. The hydrodynamic model was obtained by the depth-average of Navier Stockes’ equations forced by the terms of radiation stresses induced by waves. The sedimentary model SEDSIM developed by Martinez and Harbaugh computed, by using empirical formulations, the transport, sorting, erosion and deposit of sediment. The numerical simulations computed the impact of a realistic storm event on a relatively realistic microtidal beach with wave-formed sand bars. The results show that after 15 h of storm, the beach receded on more than 20 m. Two sedimentary bars and an orthogonal sand structure were removed and levelled. A tendency towards a single bar was observed.</div>","PeriodicalId":100980,"journal":{"name":"Oceanologica Acta","volume":"24 5","pages":"Pages 417-424"},"PeriodicalIF":0.0,"publicationDate":"2001-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0399-1784(01)01168-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91211933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4