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Modelling The Advection Of Vertically Migrating Shrimp Larvae, Peter C. Rothlisberg, John A. Church, Andrew M. G. Forbes Jan 1983

Modelling The Advection Of Vertically Migrating Shrimp Larvae, Peter C. Rothlisberg, John A. Church, Andrew M. G. Forbes

Journal of Marine Research

The role of larval advection in determining the complex, large-scale patterns of immigration of penaeid postlarvae in the Gulf of Carpentaria is investigated by modelling the interaction between diurnal vertical migration of larvae with wind-forced and tidal currents. Eight vertical migration schemes are modelled in which both the timing of the migration and the position of the larvae in the water column are varied. These schemes are then coupled with both two-dimensional and three-dimensional models of the currents of the Gulf, to examine horizontal advection of larvae. When the larvae migrate vertically with a diurnal period, their horizontal advection is …


A Dead Central American Coral Reef Tract: Possible Link With The Little Ice Age, Peter W. Glynn, Ellen M. Druffel, Robert B. Dunbar Jan 1983

A Dead Central American Coral Reef Tract: Possible Link With The Little Ice Age, Peter W. Glynn, Ellen M. Druffel, Robert B. Dunbar

Journal of Marine Research

Radiocarbon analyses, stable isotopic measurements and extensive field observations were made of coral reefs off the Pacific coast of Costa Rica and Panama. These analyses showed that live coral reefs in the Gulf of Papagayo, Costa Rica, were severely depleted in number, size and variety of species, compared to reefs in the major upwelling zone of the Gulf of Panama. Coral growth in the Gulf of Papagayo consisted mainly of dead reefs that died from 150–300 years B.P. The δ18O records revealed that most of the dead reefs were exposed to relatively cool water immediately preceding death. We …


Tidal Currents, Winds And The Morphology Of Phytoplankton Spatial Structures, M. Levasseur, J. C. Therriault, L. Legendre Jan 1983

Tidal Currents, Winds And The Morphology Of Phytoplankton Spatial Structures, M. Levasseur, J. C. Therriault, L. Legendre

Journal of Marine Research

Chlorophyll a, nutrients and salinity distributions were studied at two spatial scales (10 cm and 0.25 to 2.5 km) in the St. Lawrence Estuary (Quebec, Canada), in order to investigate the role of tidal currents and winds in the formation and maintenance of spatial structures. Data were collected according to a synoptic sampling pattern using three sampling platforms simultaneously, and they were analyzed using analysis of variance. The sampling pattern was repeated on four occasions during July 1980.Analyses of variance indicated significant spatial heterogeneities of about the same magnitude at the two scales studied for chlorophyll and nutrients, whereas …


The Relative Magnitude Of Biological And Physical Sediment Reworking In An Intertidal Community, Jonathan Grant Jan 1983

The Relative Magnitude Of Biological And Physical Sediment Reworking In An Intertidal Community, Jonathan Grant

Journal of Marine Research

Tidal sediment reworking was compared to biogenic reworking by benthic-feeding fishes and macrofaunal invertebrates on an intertidal sandflat in South Carolina. Flume-determined rates of ripple migration were combined with field measurements of current velocity to characterize physical reworking. Bioturbation by dasyatid rays was measured by counting newly formed feeding excavations at low tide. On both an areal and volumetric basis, ray reworking amounted to <1% of that reworked by ripple migration. Approximately 30% of the sediment surface was covered by feeding pits during the July maximum of ray activity, with only a small proportion of these newly formed per day. Sediment ingestion by the hemichordate Saccoglossus kowalevskii, was less important than ray bioturbation in comparison to tidal sediment reworking. Sediment displacement by free-burrowing haustoriid amphipods was estimated to be important relative to other biogenic sources, but still <1% of the disturbance produced by bedform migration. However, an abundant infaunal species, the polychaete Paraonis fulgens, …


Environmental Heterogeneity And Plankton Community Structure In The Central North Pacific, T. L. Hayward, E. L. Venrick, J. A. Mcgowan Jan 1983

Environmental Heterogeneity And Plankton Community Structure In The Central North Pacific, T. L. Hayward, E. L. Venrick, J. A. Mcgowan

Journal of Marine Research

Spatial and temporal patterns of heterogeneity in nutrients (PO4, NO3), integrated water column chlorophyll, integrated water column primary production, and macrozooplankton biomass in the central North Pacific are described on spatial scales ranging from less than one to several thousand kilometers and on temporal scales from one day to 12 years. Fluctuations in these properties represent an index of the biological response of the ecosystem to physical forcing on various scales. These patterns are an important aspect of ecosystem structure because environmental perturbations may affect the outcome of biological interactions between populations. Heterogeneity in each property …


Upwelling Rates For The Equatorial Pacific Ocean Derived From The Bomb 14c Distribution, P. D. Quay, M. Stuiver, W. S. Broecker Jan 1983

Upwelling Rates For The Equatorial Pacific Ocean Derived From The Bomb 14c Distribution, P. D. Quay, M. Stuiver, W. S. Broecker

Journal of Marine Research

A north-south cross section of bomb-produced radiocarbon (14C) in the upper 1000 m of the central equatorial Pacific Ocean (CEP) was measured in April, 1979 during Leg 3 of the NORPAX shuttle experiment. The 14C shows an equatorial mixed layer depletion of ∼40‰ compared to subtropical surface waters. Upwelling of deeper, 14C depleted water maintains this minimum. Two subsurface tongues of high 14C water, found north and south of the equator, are associated with high salinity water and probably result from exchange with subtropical surface water. The continued increase in mixed layer 14C levels …


Effect Of Sea Ice Meltwater On The Alkalinity Of Seawater, E. P. Jones, A. R. Coote, E. M. Levy Jan 1983

Effect Of Sea Ice Meltwater On The Alkalinity Of Seawater, E. P. Jones, A. R. Coote, E. M. Levy

Journal of Marine Research

Alkalinity values in the top few hundred meters in Baffin Bay were about 100 μeq kg—1 above those expected from deeper values when the effect of salinity is removed. This “excess” alkalinity is attributed to calcium carbonate that precipitated from brines in sea ice and was subsequently reintroduced into the water column when the ice melted. The “excess” alkalinity is then used to estimate the amount of sea ice meltwater formed in Baffin Bay.


Helium, Neon, And Tritium In The Black Sea, Z. Top, W. B. Clarke Jan 1983

Helium, Neon, And Tritium In The Black Sea, Z. Top, W. B. Clarke

Journal of Marine Research

Measurements of the 3He/4He ratio, and concentrations of helium, neon, and tritium have been made in samples collected at station 1355 in the Black Sea during the 1975 cruise of R/V Chain. Helium concentrations increase rapidly from 400 m to about 1000 m and then less rapidly below 1000 m. The maximum He concentration excess is about 16% above solubility equilibrium. Neon concentrations are constant, within a few percent of solubility equilibrium, below 400 m. The He-Ne data thus clearly indicate a large component of radiogenic 4He in the deep water from decay of U …


Light-Shade Adaptation And Vertical Mixing Of Marine Phytoplankton: A Comparative Field Study, Paul G. Falkowski Jan 1983

Light-Shade Adaptation And Vertical Mixing Of Marine Phytoplankton: A Comparative Field Study, Paul G. Falkowski

Journal of Marine Research

The hypothesis is examined that the recent light history of phytoplankton contains information about vertical mixing processes in the euphotic zone. Chlorophyll/P700 ratios are used to estimate the degree of light or shade adaptation in natural phytoplankton communities. Along with information about the time- and light-dependent rates of change of chlorophyll/P700 ratios, a model is presented to estimate how recently populations at the surface were at the 1% light depth and vice versa. The model is based on first-order kinetics and employs a temperature correction. The model is used to estimate vertical displacement rates (i.e., piston velocities) on …


Benthos Biomass And Oxygen Deficiency In The Upwelling System Off Peru, Rutger Rosenberg, Wolf E. Arntz, Esmeralda Chumán De Flores, Luis A. Flores, Guido Carbajal, Imme Finger, Juán Tarazona Jan 1983

Benthos Biomass And Oxygen Deficiency In The Upwelling System Off Peru, Rutger Rosenberg, Wolf E. Arntz, Esmeralda Chumán De Flores, Luis A. Flores, Guido Carbajal, Imme Finger, Juán Tarazona

Journal of Marine Research

Data are presented on macrobenthic (≥ 1 mm) biomass and species composition, sulfur bacteria (Thioploca), demersal fish catches, organic content of sediment and dissolved oxygen at 65 stations (35-360 m) along the upwelling area off north Peru in 1980-1981. Oxygen concentration close to the bottom was high only down to about 20 m depth and at 20-700 m it was generally < 0.8 ml l−1. Organic content of sediment increased significantly with water depth. Macrofauna were found at all stations with a general dominance of small polychaetes. Macrofaunal biomass showed a significant positive correlation with oxygen concentration; below 0.6 ml …


The Effect Of Pressure On The Thermodynamic Properties Of Seawater, Frank J. Millero, Donald R. Schreiber Jan 1983

The Effect Of Pressure On The Thermodynamic Properties Of Seawater, Frank J. Millero, Donald R. Schreiber

Journal of Marine Research

For many thermodynamic calculations in oceanography it is necessary to know the effect of pressure (or depth) on various thermodynamic properties. … Recently, a new equation of state for sea-water (Millero et al., 1980; Millero and Poisson, 1981) has been adopted by the UNESCO/ICES/IAPSO joint panel on oceanographic tables and standards. By appropriate differentiation of this equation of state, it is possible to determine the pressure derivatives for the specific volume of seawater solutions. To estimate the effect of pressure on the partial molal thermochemical properties (Millero and Leung, 1976), it is necessary to know the partial molal volumes of"sea …


On The Mean Dynamical Balances Of The Gulf Stream Recirculation Zone, James C. Mcwilliams Jan 1983

On The Mean Dynamical Balances Of The Gulf Stream Recirculation Zone, James C. Mcwilliams

Journal of Marine Research

The time mean circulation is analyzed at a site on the southern edge of the Gulf Stream Recirculation Zone (31N, 70W) from data taken in the POLYMODE Local Dynamics Experiment. Additional mean quantities are described from a combination of dynamical assertions and inferences. The mean vorticity balance is examined to infer the mean vertical velocity and eddy relative vorticity flux divergence. The vertical velocity is found to be mostly upward and an order of magnitude larger than the downward surface Ekman pumping. In the mean heat, salt, density, and potential vorticity budgets, the mean advections of these quantities are nonzero, …


Comparative Biogeochemistry Of Water In Intertidal Onuphis (Polychaeta) And Upogebia (Crustacea) Burrows: Temporal Patterns And Causes, Robert C. Aller, Josephine Y. Yingst, William J. Ullman Jan 1983

Comparative Biogeochemistry Of Water In Intertidal Onuphis (Polychaeta) And Upogebia (Crustacea) Burrows: Temporal Patterns And Causes, Robert C. Aller, Josephine Y. Yingst, William J. Ullman

Journal of Marine Research

The burrows of macrobenthos represent an important class of sedimentary microenvironments which significantly influence chemical, biological, and physical characteristics of a deposit. In intertidal regions, the time-dependent changes in composition during ebb-tide of water contained in burrows is a sensitive indicator of biogenic and abiogenic chemical reactions in burrow walls and adjacent sediment. Comparison of time series water samples taken from Onuphis jenneri (polychaete) and Upogebia affinis (crustacean) burrows in the same tidal flat demonstrate substantial differences in biogeochemical microenvironments despite the spatial proximity of the two species. Both types of burrows are influenced by the same general kinds of …


On The Variability Of The Loop Current In The Gulf Of Mexico, W. Sturges, J. C. Evans Jan 1983

On The Variability Of The Loop Current In The Gulf Of Mexico, W. Sturges, J. C. Evans

Journal of Marine Research

It is of considerable interest to know to what extent offshore currents may drive flows on the continental shelf. We have used the northernmost position of the Loop Current, from hydrographic data, to piece together a time series 13 years long. This record samples the lowest frequencies well but undersamples the amplitude of variations with periods of ∼8 months by a factor of 2. The "annual" variation of the Loop Current appears to be a relatively broad spectral peak rather than a sharp spectral line. We find as much power at periods near 30 months as at periods near a …


Relationship Of Water Motion To The Shallow Water Distribution And Morphology Of Two Species Of Sea Urchins, Andrew L. Lissner Jan 1983

Relationship Of Water Motion To The Shallow Water Distribution And Morphology Of Two Species Of Sea Urchins, Andrew L. Lissner

Journal of Marine Research

A 13-month field and laboratory study was conducted at Santa Catalina Island, California, USA to determine some of the effects of water motion on the shallow water distribution of the sea urchin Centrostephanus coronatus Verrill. The depth distribution of another sea urchin species, Strongylocentrotus franciscanus (A. Agassiz), includes shallow areas of strong water motion (<2 m depth) from which C. coronatus is absent. Differences in attachment strength and morphology of the two species were investigated as possible mechanisms affecting the differences in depth distribution. Density of C. coronatus along subtidal transects generally increased with increased depth, ranging from 0 individuals at depths less than …


The Role Of Colloid Chemistry In Providing A Source Of Iron To Phytoplankton, Mark L. Wells, Niko G. Zorkin, A. G. Lewis Jan 1983

The Role Of Colloid Chemistry In Providing A Source Of Iron To Phytoplankton, Mark L. Wells, Niko G. Zorkin, A. G. Lewis

Journal of Marine Research

Culture experiments with the coastal marine diatom Thalassiosira pseudonana (WHOI clone 3H) demonstrate that, as an iron source, freshly prepared colloidal ferric hydroxide can produce better cell yield than the more crystalline goethite or hematite, Ageing or heating of the prepared ferric hydroxide stock causes a reduction in cell yield. This reduction appears to be related to increased thermodynamic stability of the colloid as suggested by thermogravimetric analysis and relative dissolution rates. The reduction in cell yield can be prevented by the addition of the chelating agent EDTA prior to, but not after, ageing or heating of the ferric hydroxide …


Oceanic Property Transport, Lagrangian Particle Statistics, And Their Prediction, R. E. Davis Jan 1983

Oceanic Property Transport, Lagrangian Particle Statistics, And Their Prediction, R. E. Davis

Journal of Marine Research

The relationship between the transport of scalar properties and the statistics of material particle motion is examined. It is shown that evolution of the mean concentration field is determined by the statistics of single particles while two particle statistics describe the typical dispersal of individual property clouds. It is argued that oceanic observations of quasi-Lagrangian floats provide a useful and direct description of lateral advection and eddy dispersal. A simple model for predicting statistics of particle dispersal from Eulerian statistics of velocity is advanced. This model is tested against simulations of particle motion in random two-dimensional velocity fields with prescribed …


Vertical Motion Of The Thermocline, Nitracline And Chlorophyll Maximum Layers In Relation To Currents On The Southern California Shelf, J. J. Cullen, E. Stewart, E. Renger, R. W. Eppley, C. D. Winant Jan 1983

Vertical Motion Of The Thermocline, Nitracline And Chlorophyll Maximum Layers In Relation To Currents On The Southern California Shelf, J. J. Cullen, E. Stewart, E. Renger, R. W. Eppley, C. D. Winant

Journal of Marine Research

A continuous four-day time series of nitrate concentration, temperature, chlorophyll fluorescence, and currents, sampled at fixed depths, revealed that distributions of temperature and nitrate could be accounted for by vertical motions in the water column associated with the semidiurnal internal tide and internal waves. A probable mixing event was observed: the transport of nitrate into the surface-layer associated with shear instabilities generated by internal waves. On temporal scales of less than a few hours, the variation of chlorophyll fluorescence could also be explained by vertical advection. However, on longer scales, swimming behavior of the phytoplankton assemblage (dominated by Ceratium spp. …


Lagrangian Eddy Statistics From Surface Drifters In The Eastern North Atlantic, Alain Colin De Verdiere Jan 1983

Lagrangian Eddy Statistics From Surface Drifters In The Eastern North Atlantic, Alain Colin De Verdiere

Journal of Marine Research

In 1976–1977, 16 surface drifters were seeded regularly in an area about 100 km in diameter, providing a good opportunity to study diffusion induced by the mesoscale eddies present in this part of the eastern North Atlantic. It is found herein that Taylor's formula relating the diffusivity (rate of dispersion) of marked fluid parcels to the integral of the Lagrangian correlation function is accurate up to 30 days. The diffusivity, initially zero, reaches a plateau after about 10 days. The diffusivities associated with the time scale of the energy containing eddies (30 days) are 2.3 107 cm2/s …


Regulation Of Phytoplankton Communities By Physical Processes In Upwelling Ecosystems, Walker O. Smith, George W. Heburn, Richard T. Barber, James J. O'Brien Jan 1983

Regulation Of Phytoplankton Communities By Physical Processes In Upwelling Ecosystems, Walker O. Smith, George W. Heburn, Richard T. Barber, James J. O'Brien

Journal of Marine Research

Sinking rates of particles were superimposed on the x-z-t current field observed at 15S off the coast of San Juan, Peru in March–May, 1977 to calculate particle trajectories in the upwelling circulation. Vertical velocities were calculated by a modified variational objective analysis technique using the measured onshore and longshore currents in conjunction with the physical constraint of mass continuity. The calculated vertical flow showed considerable temporal and spatial variability, with the mean vertical transport varying by two orders of magnitude over the 16 km wide continental shelf. Changes in direction occurred rapidly (within 24 h) as has been observed for …


Equatorial Ocean Response To Growing And Moving Wind Systems With Application To The Atlantic, R. H. Weisberg, T. Y. Tang Jan 1983

Equatorial Ocean Response To Growing And Moving Wind Systems With Application To The Atlantic, R. H. Weisberg, T. Y. Tang

Journal of Marine Research

Investigation is made into the response of an equatorial ocean to growing and moving zonal wind systems as motivated by observations of maximum upwelling central to the equatorial Atlantic basin and westward progressing thermal and momentum signatures near the surface. Analytical solutions to the linear, reduced gravity, equatorial β-plane equations of motion subject to a long wave approximation are given for three easterly forcing functions: 1) linearly expanding fetch with constant stress, 2) linearly expanding fetch and stress, and 3) constant fetch and stress, translating westward. The results, as they may relate to the equatorial Atlantic Ocean, are discussed.


Enhanced Growth Of A Filter-Feeding Bivalve By A Deposit-Feeding Polychaete By Means Of Nutrient Regeneration, James R. Weinberg, Robert B. Whitlatch Jan 1983

Enhanced Growth Of A Filter-Feeding Bivalve By A Deposit-Feeding Polychaete By Means Of Nutrient Regeneration, James R. Weinberg, Robert B. Whitlatch

Journal of Marine Research

Sediment reworking and tube irrigation by the deposit-feeding polychaete, Clymenella torquata, reduced the quantity of particulate organic matter (POM) at the sediment-water interface and increased concentrations of dissolved nutrients (nitrite, ammonia, silicate, phosphate) in the water overlying laboratory microcosms. To determine the effect of these changes on growth of the filter-feeding bivalve, Gemma gemma, clams of the same initial size were grown under different laboratory conditions, representing all combinations of the following three treatments: (a) presence or absence of light, (b) presence or absence of C. torquata, and (c) proximity to C. torquata (clams living in sediment with worms or …


A Subsurface Particle Maximum Layer And Enhanced Microbial Activity In The Secondary Nitrite Maximum Of The Northeastern Tropical Pacific Ocean, P. C. Garfield, T. T. Packard, G. E. Friederich, L. A. Codispoti Jan 1983

A Subsurface Particle Maximum Layer And Enhanced Microbial Activity In The Secondary Nitrite Maximum Of The Northeastern Tropical Pacific Ocean, P. C. Garfield, T. T. Packard, G. E. Friederich, L. A. Codispoti

Journal of Marine Research

Profiles of light transmission, dissolved oxygen, dissolved nutrients, electron transport system (ETS) activity, temperature and salinity were made in the northeastern tropical Pacific Ocean. A particle maximum at 150–300 m within the oxygen minimum and secondary nitrite maximum was associated with the salinity maximum of Subtropical Subsurface Water. A subsurface maximum in ETS activity was also found to be associated with the secondary nitrite maximum and the particle maximum. Persistence of these features at a constant depth and their location within a minimum in vertical static stability suggest an advective and/or in situ origin for the particles and an in …


Equatorial Current Measurements, I. Moored Observations, James R. Luyten Jan 1982

Equatorial Current Measurements, I. Moored Observations, James R. Luyten

Journal of Marine Research

The low frequency fluctuations in the western Indian Ocean are dominated by energetic variability with relatively small horizontal and vertical scales. The time series of horizontal current and temperature exhibit a number of energetic events which, for the most part, are not sufficiently resolved to assign a spatial scale to the underlying process....


On The Movements Of Deep Mesoscale Eddies In The North Atlantic, Doron Nof Jan 1982

On The Movements Of Deep Mesoscale Eddies In The North Atlantic, Doron Nof

Journal of Marine Research

A simplified three layer model is considered in order to examine the movements of deep mesoscale eddies such as the isolated Mediterranean eddies observed off the Bahamas. These anticyclonic eddies are found in the permanent thermocline more than 6000 km away from their parent water mass and are characterized by a lens-like cross section....


Temporal And Spatial Patterns Of Monsoonal Upwelling Along Arabia: A Modem Analogue For The Interpretation Of Quaternary Sst Anomalies, Warren L. Prell Jan 1982

Temporal And Spatial Patterns Of Monsoonal Upwelling Along Arabia: A Modem Analogue For The Interpretation Of Quaternary Sst Anomalies, Warren L. Prell

Journal of Marine Research

Several lines of evidence suggest that monsoonal circulation and its associated upwelling in the Arabian Sea have experienced significant fluctuations during the past 105 years. To construct an analogue model to interpret such changes, we have used the monthly average sea-surface temperature (SST) data from Hastenrath and Lamb (1979) to define the temporal and spatial pattern of upwelling along Arabia....


Wave Damping By Monomolecular Surface Films And Their Chemical Structure. Part I: Variation Of The Hydrophobic Part Of Carboxylic Acid Esters, Heinrich Hühnerfuss, Philipp Lange, Wolfgang Walter Jan 1982

Wave Damping By Monomolecular Surface Films And Their Chemical Structure. Part I: Variation Of The Hydrophobic Part Of Carboxylic Acid Esters, Heinrich Hühnerfuss, Philipp Lange, Wolfgang Walter

Journal of Marine Research

Plunger generated 1.0, 1.3, 1.8, 2.0, 2.3, and 2.5 Hz waves have been used to investigate the direct wave damping effect of carboxylic acid ester surface films….


A Comparison Of Moored And Free-Drifting Sediment Traps Of Two Different Designs, Nick Staresinic, Klaus Von Bröckel, Nenad Smodlaka, C. Hovey Clifford Jan 1982

A Comparison Of Moored And Free-Drifting Sediment Traps Of Two Different Designs, Nick Staresinic, Klaus Von Bröckel, Nenad Smodlaka, C. Hovey Clifford

Journal of Marine Research

The Kiel conical sediment trap and a 3:1 right cylinder were simultaneously deployed in both free-drifting and moored modes on four separate occasions over the Peruvian shelf in order to compare downward flux measurements derived from each….


On Forced Coastal Trapped Waves At Low Latitudes In A Stratified Ocean, R. D. Romea, J. S. Allen Jan 1982

On Forced Coastal Trapped Waves At Low Latitudes In A Stratified Ocean, R. D. Romea, J. S. Allen

Journal of Marine Research

The response on the continental shelf and slope of a baroclinic ocean to driving by an alongshore wind stress at the coast…


Perspectives Of Research On Detritus: Do Factors Controlling The Availability Of Detritus To Macroconsumers Depend On Its Source?, K. R. Tenore, L. Cammen, S. E.G. Findlay, N. Phillips Jan 1982

Perspectives Of Research On Detritus: Do Factors Controlling The Availability Of Detritus To Macroconsumers Depend On Its Source?, K. R. Tenore, L. Cammen, S. E.G. Findlay, N. Phillips

Journal of Marine Research

Various factors have been suggested as regulating the availability of detritus to detritivores, e.g., particle-size and microbial dynamics, nutritional composition of detritus per se, and chemical inhibitors/ enhancers. These factors might vary in importance depending on detritus source: fecal pellets, vascular plants, or seaweed-derived detritus. We review the literature to evaluate the above factors and suggest that future research on detritus should consider regulatory mechanisms which depend on detritus type.