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The Role Of Double Diffusive Interleaving In Mesoscale Dynamics: An Hypothesis, Eric S. Posmentier, A. D. Kirwan Jr. Jan 1985

The Role Of Double Diffusive Interleaving In Mesoscale Dynamics: An Hypothesis, Eric S. Posmentier, A. D. Kirwan Jr.

Journal of Marine Research

It is hypothesized that double diffusive interleaving can act to enhance the temperature, salinity and buoyancy signatures of some mesoscale structures. The hypothesis is founded on theoretical results showing that the fluxes produced by double diffusive interleaving can have counter-gradient components, and on the observations that isolated mesoscale rings have a long lifetime and that there is intense interleaving in the frontal zone typically surrounding the ring. Quantitative examples for a warm and a cold core ring demonstrate the feasibility of the hypothesis. Some suggestions are given for extending the hypothesis to include other mesoscale features. Also theoretical investigations and …


Analyses Of The Settling Velocities Of Fecal Pellets From The Subtidal Polychaete Amphicteis Scaphobranchiata, Paul D. Komar, Gary L. Taghon Jan 1985

Analyses Of The Settling Velocities Of Fecal Pellets From The Subtidal Polychaete Amphicteis Scaphobranchiata, Paul D. Komar, Gary L. Taghon

Journal of Marine Research

Measured settling velocities of fecal pellets produced by Amphicteis scaphobranchiata, a deposit-feeding subtidal polychaete worm, are analyzed to determine the effects of pellet shapes and to arrive at improved formulae for predicting settling rates of fecal pellets in general. Drag coefficients calculated from the measured settling velocities and pellet densities decrease with increasing Reynolds numbers, the trend roughly paralleling the drag-coefficient curve for spheres but having higher values due to the nonspherical shapes of the pellets. No clear dependence could be found on the pellet shapes, however, when the shape is expressed as pellet elongation (length/width). Comparisons are also made …


Tidal Rectification And Frontal Circulation On The Sides Of Georges Bank, John W. Loder, Daniel G. Wright Jan 1985

Tidal Rectification And Frontal Circulation On The Sides Of Georges Bank, John W. Loder, Daniel G. Wright

Journal of Marine Research

Using Wright and Loder's (l985a,b) depth-dependent tidal rectification model and Garrett and Loder's (1981) diagnostic frontal circulation model, predictions of the residual circulation associated with the topographic rectification of tidal currents and the summertime density field on the northwestern and open ocean sides of Georges Bank are made and compared with observations. In general, the estimates of both wintertime and summertime along-isobath currents are in qualitative agreement with observations, but the agreement between predicted and observed cross-isobath currents is poor. The circulation associated with tidal rectification is primarily along isobaths in an anticyclonic sense around the Bank at all depths. …


Effects Of The Marine Deposit-Feeders Heteromastus Filiformis (Polychaeta), Macoma Balthica (Bivalvia), And Tellina Texana (Bivalvia) On Averaged Sedimentary Solute Transport, Reaction Rates, And Microbial Distributions, Robert C. Aller, Josephine Y. Yingst Jan 1985

Effects Of The Marine Deposit-Feeders Heteromastus Filiformis (Polychaeta), Macoma Balthica (Bivalvia), And Tellina Texana (Bivalvia) On Averaged Sedimentary Solute Transport, Reaction Rates, And Microbial Distributions, Robert C. Aller, Josephine Y. Yingst

Journal of Marine Research

Experimental studies of the deposit-feeders Heteromastus flliformis, Tellina texana, and Macoma balthica demonstrate that, at natural population abundances, each species has major effects on sediment overlying water solute transport, bulk sediment reaction rates, and microbial distributions. Using Cl− as a conservative tracer, one-dimensional transport models show that the effective diffusion coefficient, De, in the presence of these macrofauna is ∼2–5× the molecular diffusion value in the upper 8–12 cm of sediment. In general, the exact value of De is time dependent as shown by time-course experiments with Heteromastus and by comparison of one-dimensional model predictions with …


Factors Affecting The Distribution Of The Introduced Bivalve, Mercenaria Mercenaria, In A California Lagoon—The Importance Of Bioturbation, Richard C. Murphy Jan 1985

Factors Affecting The Distribution Of The Introduced Bivalve, Mercenaria Mercenaria, In A California Lagoon—The Importance Of Bioturbation, Richard C. Murphy

Journal of Marine Research

Quantitative surveys of the Colorado Lagoon and Marine Stadium (Long Beach, California, USA) indicated that the bivalve communities in the Lagoon and in the Stadium were dramatically different, even though water exchanged freely between the two systems for most of the year. In the Lagoon the mean total bivalve density was 143 · m−2 with a density of the introduced clam, Mercenaria mercenaria, of 78 · m−2. In the Stadium the mean total clam density was 57 · m−2 and M. mercenaria was absent. In the Lagoon, bivalve populations were dominated by suspension-feeders, while in the …


Biological Observations In The Marginal Ice Zone Of The East Greenland Sea, Sharon L. Smith, Walker O. Smith, Louis A. Codispoti, David L. Wilson Jan 1985

Biological Observations In The Marginal Ice Zone Of The East Greenland Sea, Sharon L. Smith, Walker O. Smith, Louis A. Codispoti, David L. Wilson

Journal of Marine Research

The distribution of nutrients, phytoplankton and zooplankton was investigated during summer, 1983 in the marginal ice zone of the East Greenland Sea. Nutrient levels, especially inorganic nitrogen, were extremely low, and probably limited the growth of phytoplankton during this period. An ammonium maximum at the base of the euphotic zone, generally around 50 m, was found repeatedly and appeared to be controlled by active nitrogen regeneration and decreased ammonium uptake at low light levels. Chlorophyll a levels were elevated at the ice-edge, but were even higher in an area influenced by an eddy. Species of zooplankton were accurate indicators of …


Large Scale Pattern Of Recruitment By The Labrid, Semicossyphus Pulcher: Causes And Implications, Robert K. Cowen Jan 1985

Large Scale Pattern Of Recruitment By The Labrid, Semicossyphus Pulcher: Causes And Implications, Robert K. Cowen

Journal of Marine Research

The pattern of recruitment of sheephead, Semicossyphus pulcher, is described throughout a major portion of its range over a period of 7–9 years. The relative recruitment success was determined using both field transects and age-structure data. The observed pattern of recruitment was compared to both spatial and year-to-year variations in the current regime within the region using both average flow data (CalCOFI data base) and satellite imagery. It was found that in areas with larval sources to the north and south, recruitment occurred consistently from year-to-year. However, in areas where there was no larval sources "upstream" of the typical current …


Wind-Driven Mid-Ocean Baroclinic Gyres Over Topography: A Circulation Equation Extending The Sverdrup Relation, R. A. De Szoeke Jan 1985

Wind-Driven Mid-Ocean Baroclinic Gyres Over Topography: A Circulation Equation Extending The Sverdrup Relation, R. A. De Szoeke

Journal of Marine Research

What is the circulation driven by wind stress in a stratified ocean above topography? This question was answered by Sverdrup (1947) for vertically integrated transport over flat topography only. By applying the ideas and methods of Rhines and Young (1982a,b), a modified form of the Sverdrup transport relation can be derived for the case of stratification and topography in certain circumstances. This circulation equation is, in quasigeostrophic form,J(Ψ, βy + χf0h′T/H) = − χf0−1gAH J(βy, h′T) + z · ∇xτ/ …


Annual Cycles Of Nutrients And Chlorophyll In Narragansett Bay, Rhode Island, Michael E. Q. Pilson Jan 1985

Annual Cycles Of Nutrients And Chlorophyll In Narragansett Bay, Rhode Island, Michael E. Q. Pilson

Journal of Marine Research

Nutrient concentrations in Narragansett Bay change in a regular way through the seasons, so that characteristic and well defined cycles are observed, but are different for each nutrient. The cyclic changes are not explainable by processes in the water column alone, nor by advection, even though the replacement time of water in the bay is only 10–40 days. It appears possible to incorporate much of the cycling activity in 13-m3 microcosms, so these must include the dominating features of the complex biogeochemical processes involved. Observations in the microcosms suggest that the processes maintaining the annual cycles are sufficiently strong …


Coupling Of The Gulf Of California To Large-Scale Interannual Climatic Variability, Tim R. Baumgartner, Niels C. Christensen Jr. Jan 1985

Coupling Of The Gulf Of California To Large-Scale Interannual Climatic Variability, Tim R. Baumgartner, Niels C. Christensen Jr.

Journal of Marine Research

The source of interannual changes in the ocean climate of the Gulf of California, indicated by sea level and shore temperature anomalies, is determined by comparison with large-scale circulation in the Pacific Ocean and atmosphere. Independent modes of variability in the large-scale circulation are defined by empirical orthogonal function analysis of eight time series representing the principle ocean currents and surface wind systems. Interannual ocean climate in the Gulf of California is related only to the equatorial mode of variability commonly known as the El Niño/Southern Oscillation. There is no discernible relationship between the Gulf and independent modes of variability …


Spectral "Fingerprinting" Of Phytoplankton Populations By Two-Dimensional Fluorescence And Fourier-Transform-Based Pattern Recognition, P. B. Oldham, E. J. Zillioux, I. M. Warner Jan 1985

Spectral "Fingerprinting" Of Phytoplankton Populations By Two-Dimensional Fluorescence And Fourier-Transform-Based Pattern Recognition, P. B. Oldham, E. J. Zillioux, I. M. Warner

Journal of Marine Research

The selectivity of fluorescence spectroscopy is exploited for the characterization of marine algae. Two-dimensional, digital images of in vivo fluorescence intensity versus excitation and emission wavelengths, called excitation-emission matrices (EEMs), are used as spectral "fingerprints" for marine phytoplankton populations. Fourier-transform-based pattern recognition is described along with its inherent strengths and weaknesses for the analysis of natural populations. The EEMs of unknown algae are compared to a library of standard EEMs representing 23 algal species and 6 classes with better than 80% accuracy. The EEMs acquired under different physiological conditions are used in determining pattern recognition reliability. The potential for fingerprinting …


Spectral Observations Of Pigment Fluorescence In Intermediate Depth Waters Of The North Pacific, William W. Broenkow, Alan J. Lewitus, Mark A. Yarbrough Jan 1985

Spectral Observations Of Pigment Fluorescence In Intermediate Depth Waters Of The North Pacific, William W. Broenkow, Alan J. Lewitus, Mark A. Yarbrough

Journal of Marine Research

Vertical profiles at three stations off the California coast showed spectral differences between fluorescence at the primary fluorescence maxima (near 100 m) and the deeper maximum (near 800 m). Two broad-band excitation and several narrow or high-pass emission filters were used with an in situ fluorometer to 1500 m. Interpretation of these data suggests: (1) chlorophyll a was found throughout the water column, with intermediate depth fluorescence about one-third the intensity of that in the primary maximum; (2) phycobilin fluorescence was stronger at intermediate depths than near the surface; and (3) a pigment which fluoresces beyond 700 nm was also …


The Role Of Bacteria In The Turnover Of Organic Carbon In Deep-Sea Sediments, Gilbert T. Rowe, Jody W. Deming Jan 1985

The Role Of Bacteria In The Turnover Of Organic Carbon In Deep-Sea Sediments, Gilbert T. Rowe, Jody W. Deming

Journal of Marine Research

The cycling of organic carbon in the deep sea was inferred from measurements of sediment trap and box core samples taken on the Biscay and Demerara abyssal plains of the North Atlantic. Of the input of organic carbon to the bottom, less than 10% was buried, i.e., not consumed biologically. Based on laboratory measurements of bacterial activity in the sediment samples, incubated under in situ temperature and pressure, it was possible to attribute at least 13 to 30% of the total inferred biological consumption of organic carbon to microbial utilization. The complementarity of results from these biochemical and microbiological measurements …


Interstitial Water Iodine Enrichments In Sediments From The Eastern Pacific, S. J. Wakefield, H. Elderfield Jan 1985

Interstitial Water Iodine Enrichments In Sediments From The Eastern Pacific, S. J. Wakefield, H. Elderfield

Journal of Marine Research

The vertical distribution of iodine has been examined in interstitial waters of sediment cores from the Peru Basin, Bauer Basin, Guatemala Basin and the East Pacific Rise and the sediments have been analyzed for iodine and organic carbon. Interstitial water profiles show a strong enrichment of iodine at the sediment surface relative to overlying sea water. This enrichment is much greater than would have been expected had all the iodine originated solely from the breakdown of newly sedimented plankton. This implies recycling of iodine in the region of the water-sediment interface with most of the upward diffusing iodine being rescavenged …


Drifter Spectra And Diffusivities, John F. Middletown Jan 1985

Drifter Spectra And Diffusivities, John F. Middletown

Journal of Marine Research

The relationships between Eulerian and Lagrangian (or drifter) diffusivities and spectra are explored in detail using the Lagrangian correlation predictor due to Corrsin (1959). The analysis, applicable to homogeneous, isotropic velocity fields shows that an important dimensionless parameter in the Euler-Lagrange transformations is the ratio α of Eulerian integral TE to advective Ta time scales. It is found that the diffusivity may be approximated to within 10% by the function qν2TE (q2 + α2)−1/2 where ν2 is the mean-square velocity component and q ≃ 0.63. This result is found …


The Concentrating Of Organisms At Fronts: A Cold-Water Fish And A Warm-Core Gulf Stream Ring, Donald B. Olson, Richard H. Backus Jan 1985

The Concentrating Of Organisms At Fronts: A Cold-Water Fish And A Warm-Core Gulf Stream Ring, Donald B. Olson, Richard H. Backus

Journal of Marine Research

Net hauls made in and around a warm-core Gulf Stream ring in April and June 1982 suggest a concentrating of the mesopelagic fish Benthosema glaciale (family Myctophidae) in the frontal zone at the east edge of the ring. In April, Benthosema was found in very small numbers in the two-month old ring, as was to be expected from the subpolar-temperate distribution of this fish and the warm-water origin and age of the ring. By June, age-0 fish had been recruited to the population susceptible to capture by the midwater trawl. These young fish were about five times as abundant at …


Blooms Of The Pelagic Tunicate, Dolioletta Gegenbauri: Are They Associated With Gulf Stream Frontal Eddies?, Don Deibel Jan 1985

Blooms Of The Pelagic Tunicate, Dolioletta Gegenbauri: Are They Associated With Gulf Stream Frontal Eddies?, Don Deibel

Journal of Marine Research

Satellite-directed sampling was used to determine whether blooms of Dolioletta gegenbauri are associated with warm filaments of Gulf Stream frontal eddies. Radio-transmitting drogues were used to mark the center of the bloom so that physical and biological covariables could be measured inside and outside of bloom waters.The bloom was not in the warm filament of a frontal eddy, but was 60 – 70 km northwest of the temperature front between outer-shelf water and the Gulf Stream—in upwelled water probably originating from the eddy's cold core. This cold-core remnant (CCR) water was stranded between 2 middle-shelf fronts.The doliolid bloom resulted from …


Association Of An Ice-Nucleating Pseudomonad With Cultures Of The Marine Dinoflagellate, Heterocapsa Niei, Ray Fall, Russell C. Schnell Jan 1985

Association Of An Ice-Nucleating Pseudomonad With Cultures Of The Marine Dinoflagellate, Heterocapsa Niei, Ray Fall, Russell C. Schnell

Journal of Marine Research

The observations that terrestrial ice nuclei can have a biogenic origin and that certain bacteria can initiate freezing at exceptionally warm temperatures (−1.5°C) are now well documented. Less well understood are active ice nuclei (−2 to −5°C) found in sea water, marine fog and the marine atmosphere in general. Recently, the authors have isolated an ice nucleation-active (INA) bacterial strain (FB 1032) from cultures of the marine dinoflagellate, Heterocapsa niei. FB 1032 is halotolerant and phenotypically similar to Pseudomonas fluorescens biotype G, although it differs from biotype G strains in its bacteriophage sensitivity and expression of the INA phenotype. …


Seasonal Variability Of The Surface Dynamic Topography In The Tropical Atlantic Ocean, Jacques Merle, Sabine Arnault Jan 1985

Seasonal Variability Of The Surface Dynamic Topography In The Tropical Atlantic Ocean, Jacques Merle, Sabine Arnault

Journal of Marine Research

The seasonal changes of the surface dynamic topography are studied using a merged data set including MDT, XBT and Nansen observations, collected in the 20S–30N tropical Atlantic until 1978. Two regions of maximum seasonal variability appear. One lies north of the equator extending zonally approximately under the mean position of the Inter-Tropical Convergence Zone (ITCZ). The second one is found in the eastern equatorial region (Gulf of Guinea). The two regions vary out of phase and are separated by a pivot point around 25W in the equatorial plane. Another near 180° phase change is observed at the northern edge of …


Differential Responses Of Two Nearshore Infaunal Assemblages To Experimental Petroleum Additions, Jeffrey L. Hyland, Eva J. Hoffman, Donald K. Phelps Jan 1985

Differential Responses Of Two Nearshore Infaunal Assemblages To Experimental Petroleum Additions, Jeffrey L. Hyland, Eva J. Hoffman, Donald K. Phelps

Journal of Marine Research

Empirical support is provided for the hypothesis that benthic communities found in relatively constant and predictable environments are less stable (resistant and resilient) following unusual disturbances than lower-diversity communities found in more inconstant and unpredictable environments. A less diverse benthic community (i.e., the Streblospio-Tubificoides assemblage) inhabiting an inconstant and unpredictable, shallow marsh cove was disturbed less and recovered faster from an experimental addition of No. 2 fuel oil, than the more diverse benthos (i.e., the Nucula-Mediomastus assemblage) inhabiting a relatively more constant and predictable, deeper coastal embayment. Disturbed sediment had a stimulatory effect on most populations in the marsh and …


Seasonal Oxygen Cycling And Primary Production In The Sargasso Sea, W. J. Jenkins, J. C. Goldman Jan 1985

Seasonal Oxygen Cycling And Primary Production In The Sargasso Sea, W. J. Jenkins, J. C. Goldman

Journal of Marine Research

The hydrographic record at Station S in the Sargasso Sea shows the development of a subsurface oxygen maximum within the euphotic zone which must be of photosynthetic origin. Consideration of insolation, heat budgets and available 3He/3H data yields an estimate of the order of 5 M m−2 y−1 for the vertically integrated oxygen production rate. Gas exchange calculations reveal a similar oxygen flux leaving the surface, and examination of respiration cycles below the euphotic zone yields consistent results. Such results point to new production of the order of 50 g C m−2 y−1 …


Western Boundary Circulation Driven By An Alongshore Wind: With Application To The Somali Current System, Julian P. Mccreary, Pijush K. Kundu Jan 1985

Western Boundary Circulation Driven By An Alongshore Wind: With Application To The Somali Current System, Julian P. Mccreary, Pijush K. Kundu

Journal of Marine Research

The linear, continuously stratified, eastern-boundary model of McCreary (1981) is extended to apply to a western ocean boundary and to wind fields with curl. The model has vertical and horizontal mixing, and both types of mixing are important in its dynamics. Solutions are represented as expansions in vertical modes, and the dynamics of low-order and high-order modes are very different. Low-order modes tend to be in Sverdrup balance in the interior ocean, and to form a Munk layer at the coast. High-order modes are in Ekman balance in the interior ocean, and the coastal balance is two dimensional.The model is …


A Zero Potential Vorticity Model Of The North Brazilian Coastal Current, G. T. Csanady Jan 1985

A Zero Potential Vorticity Model Of The North Brazilian Coastal Current, G. T. Csanady

Journal of Marine Research

The North Brazilian Coastal Current (NBCC) is idealized as an inertial, surface layer jet of equatorial origin, intruding along the coast into a northern water mass of constant, positive potential vorticity. Dissipation is accounted for by supposing that some equatorial water leaks out in the northwest corner of the intrusion. The problem is closed by adopting the free streamline boundary condition (between the northern and equatorial water masses) of continuous layer depth and velocity.Calculations are made for flow (intruding and return) supposed parallel to the coast; this approximation is verified à posteriori. The results show a narrow intrusion region along …


The Annual Cycle In The Central Equatorial Pacific Ocean, Peter R. Gent Jan 1985

The Annual Cycle In The Central Equatorial Pacific Ocean, Peter R. Gent

Journal of Marine Research

A linear, periodic model using the long-wave approximation on the equatorial β-plane is forced by the annual cycle of zonal wind stress from the Pacific Ocean. The forcing is deduced from the monthly data set of Hellerman and Rosenstein. The model results are compared with observations of the annual cycle which are mainly of temperature in the upper central Pacific Ocean from the Hawaii-Tahiti shuttle experiment. The agreement is good in phase, but poor in amplitude. The effect on model results of different friction assumptions and coefficients shows that no tuning of the parameters significantly improves the comparison with …


Sofar Float Trajectories Associated With The Newfoundland Basin, William J. Schmitz Jr. Jan 1985

Sofar Float Trajectories Associated With The Newfoundland Basin, William J. Schmitz Jr.

Journal of Marine Research

The connection between the current systems and water masses in the Newfoundland Basin and the North Atlantic Subtropical Gyre has been controversial for some time. SOFAR floats have now been launched in the Newfoundland Basin, and others observed to move there. Floats were typically deployed in pairs at nominal depths of 700 m (thermocline level) and 2000 m (deep). A thermocline level float set in the North Atlantic Current near 45N drifted to about 50N before recirculating, whereas a deep float deployed concurrently eventually moved south and west around the Grand Banks. A float pair deployed in the interior of …


Habitat Complexity Of Polychaete Tube-Caps: Influence Of Architecture On Dynamics Of A Meioepibenthic Assemblage, Susan B. Bell Jan 1985

Habitat Complexity Of Polychaete Tube-Caps: Influence Of Architecture On Dynamics Of A Meioepibenthic Assemblage, Susan B. Bell

Journal of Marine Research

A series of field experiments was conducted in a shallow sandflat in Tampa Bay, Florida, to examine the relationship between the abundance and diversity of meiofauna and the architectural complexity of tube-caps constructed by the polychaete, Diopatra cuprea. Two groups of azoic tube-caps were utilized: 1) tube-caps collected from the field and defaunated in the laboratory or 2) tube-caps created in laboratory aquaria with azoic sediment under controlled conditions. Tube-caps were designated "high" or "low" complexity based upon the amount of shell hash incorporated into tube-cap structure, replanted into sediments at 2 sites during February–April 1982 and collected 1, 3, …


Evolution Of Sea-Surface Temperature In The Tropical Atlantic Ocean During Fgge, 1979: Ii. Oceanographic Fields And Heat Balance Of The Mixed Layer, Robert L. Molinari, John F. Festa, Eric Marmolejo Jan 1985

Evolution Of Sea-Surface Temperature In The Tropical Atlantic Ocean During Fgge, 1979: Ii. Oceanographic Fields And Heat Balance Of The Mixed Layer, Robert L. Molinari, John F. Festa, Eric Marmolejo

Journal of Marine Research

Surface meteorological and surface and subsurface oceanographic data collected during 1979 are used to describe sea-surface temperature, mixed layer depth, zonal current component and net oceanic heat gain fields and to estimate the terms in a heat balance relation for the mixed layer. The terms are evaluated monthly on a 6° of latitude by 10° of longitude grid which covers the equatorial Atlantic from 9S to 9N. The first balance tested is between changes in mixed layer temperature and surface energy fluxes. These fluxes can account for more than 75% of the variance in the original time series of the …


Three-Dimensional Shelf Circulation Along An Eastern Ocean Boundary, Julian P. Mccreary Jr., Shenn-Yu Chao Jan 1985

Three-Dimensional Shelf Circulation Along An Eastern Ocean Boundary, Julian P. Mccreary Jr., Shenn-Yu Chao

Journal of Marine Research

A linear, three-dimensional, continuously stratified model is used to study wind-driven ocean circulation near an eastern coast in the presence of a continental shelf. A simplifying assumption is that the alongshore flow field is in geostrophic balance. This assumption allows steady solutions to be obtained numerically with a very efficient scheme. As a result, it is possible to find solutions for a wide variety of model parameters and shelf profiles.A band of equatorward wind forces the ocean, and the resulting solutions have many features in common with observations at eastern boundaries. They all have a surface equatorward jet, but do …


Meiofauna-Sediment Interactions Around Subtropical Seagrass Sediments Using Factor Analysis, A. W. Decho, W. D. Hummon, J. W. Fleeger Jan 1985

Meiofauna-Sediment Interactions Around Subtropical Seagrass Sediments Using Factor Analysis, A. W. Decho, W. D. Hummon, J. W. Fleeger

Journal of Marine Research

Subtidal meiobenthic samples were collected from sediments within a seagrass bed (Thalassia testudinum) and an adjacent barren sand area in the Florida Keys. Fine-scale differences in sediment and heterogeneity, with respect to sediment grain parameters were analyzed using factor analysis. Sediment heterogeneity was related to meiofaunal distributions. Eighteen meiofaunal taxa representing 15 phyla were found. Nematodes comprised 58% of the total meiofauna. Eight gastrotrich, 26 harpacticoid, and one cyclopoid species were found. In comparing the seagrass area to the barren sand area by ANOVA, significant differences in density were noted for total meiofauna and polychaetes, but not for …


Phytoplankton Patchiness: Inferences From Particle Statistics, Andrew F. Bennett, Kenneth L. Denman Jan 1985

Phytoplankton Patchiness: Inferences From Particle Statistics, Andrew F. Bennett, Kenneth L. Denman

Journal of Marine Research

We examine the influence of mesoscale turbulence and random growth rate fields upon phytoplankton patchiness, on length scales from 1 km to 100 km and time scales from 1 day to 100 days. We consider phytoplankton concentrations with quite general nonlinear growth rate functions, such that the concentration is bounded for all time. We use, and justify the use of, particle separation statistics to deduce variance spectra of nonlinearly transformed concentration. Two growth rate models are examined: an advected field, and a locally specified field. Both lead to initial patchiness in the concentration, correlated with the growth rate field. The …