Fresh Marine Research Articles

TBT contamination of an artisanal subsistence fishery in Suva harbour, Fiji

Abstract The intertidal zone around the Suva Peninsula, Fiji, supports separate finfish and invertebrate subsistence fisheries. This important source of fresh marine food for many low-income families around metropolitan Suva is under threat from foreshore reclamation projects and from anthropogenic biochemical pollution. Damage to or loss of this invertebrate intertidal fishery would remove a significant area where urban dwellers can pursue this traditional (non-cash) means of seafood acquisition. In 1996, Suva Peninsula was considered for the development of a marina, hotel, aquarium, roads, walls, and other structures. There is also increasing evidence of a serious anthropogenic TBT (tributyltin) pollution threat to the local invertebrate fishery. Although this substance is well known to have ecologically deleterious effects, its use is unregulated in Fiji. The inputs are likely to be large commercial vessels, and in particular the shipyards around the west side of Suva Harbour, where TBT antifouling coatings are both applied and removed, the old paint debris being allowed to wash into the harbour. Inputs from small boats are probably less important as there are relatively few (

Sequence stratigraphy of the Middle Devonian Winnipegosis carbonate-prairie evaporite transition, southern Elk Point Basin

The Middle Devonian Winnipegosis reefs in the southern Saskatchewan portion of the Elk Point Basin contain extensive vadose diagenetic features, such as dissolution breccia, and cavities/caves filled by microbialite, pisolite and anhydrite. Basinal facies adjacent to reef buildups are characterized by the Ratner laminite, which consists of three brining-upward successions of laterally continuous, laminated dolomite and anhydrite. The basal cycle starts with a relatively thick unit of anhydrite-free, millimeter-scale dololaminite, changing upward into interlaminated carbonate and anhydrite, and ending with enterolithic, nodular to mosaic anhydrite. Subsequent cycles generally lack the dololaminite of the basal cycle. The Ratner laminite grades upward into the bedded to massive mosaic anhydrite of the Whitkow Member (lower Prairie Evaporite) in areas adjacent to reefs. Deposition of the Ratner laminite and the Whitkow Anhydrite is interpreted as genetically related to the vadose diagenetic processes, when the Elk Point Basin became restricted. The carbonate laminite in the basal Ratner was accumulated when seepage of fresh marine water through the barrier kept pace with the rate of evaporation, preventing a complete drawdown and desiccation of the basin. Precipitation of the laminated carbonate was stimulated by vadose diagenesis of the carbonate buildups and by microbial activity. Each Ratner brining-upward succession represents a progressive drawdown when the rate of basin brine evaporation exceeded seepage of marine water into the basin. Marine water seeping through the reefs was enriched in calcium cations by Mg++−Ca++ exchange with the limestone (dolomitization) and by dissolution of reef rocks, and was responsible for the precipitation of calcium sulphate in areas adjacent to the carbonate reefs through brine mixing processes. During vadose diagenesis of the Winnipegosis reefs and deposition of the Ratner laminite and Whitkow Anhydrite, brine level in the barred Elk Point Basin was controlled by the rate of seepage of marine water through the barrier, which in turn was controlled by eustatic sea level changes in the open ocean. The basal anhydrite-free dololaminite of the Ratner represents a Falling Stage System Tract when evaporative drawdown was largely compensated by seepage of marine water into the basin. The interlaminated carbonate and anhydrite of the middle and upper Ratner are interpreted as a Lowstand System Tract associated with evaporative drawdown and increased cyanobacterial activity under near-desiccation conditions when evaporation exceeded seepage. The Whitkow Anhydrite represents a Transgressive System Tract deposited during sea level rise in the open ocean that led to an increased rate of seepage, higher basin brine level and diminished microbial influence on bedding structures.

Accumulation of Mutagenic Xenobiotics in Fresh Water (Lake Baikal) and Marine (Hornoya Island) Ecosystems

Extracts from tissues of a wide range of aquatic organisms (plants, plankton, decapods, molluscs, fish, Baikal seals, and fish-eating birds and their eggs) from Lake Baikal and from the Selenga River estuary and tissue extracts of birds breeding on Hornoya Island (northern Norway) were assayed for mutagenicity using the Ames Salmonella/microsome test. The activities of cytochrome P-450 and the enzymes of phase II of detoxification were also studied in the liver of fish and birds. Evidence was found for the accumulation of mutagens in the food chain. The relationship of bioaccumulation to the levels of enzyme activities possessing both detoxification and activation functions is discussed in the cases of fish and birds. The accumulation of mutagens was found to depend on the activity and the level of induction of the enzymes providing the detoxification and metabolic activation in the livers of fish and birds.

Écoulement tridimensionnel à surface libre Approche h-s: Partie II

ABSTRACT The works that are the object of the present paper consist of developing a model to simulate free surface flows applicable at sea, river, and lake, under loads as various as floods, density gradient between salt water—fresh water, marine coast or gales. This model based upon finite element method, implies an approach that we called h-s. This latter privileges, as it occurs in nature for the problems that we wish to study, the horizontal dimension to vertical dimension, which under goes a special treatment. We note that the pressure can be hydrostatic or not. This method is based upon a finite element approximation along with the horizontal plane (x, y), and upon analytical one along with z. The choice of the series and the number of its terms depend on the physics of the problem and the required accuracy. We have used a hybrid element T6L for the spatial discretization. For the time discretization, we have used two schemes. The first one is that of backward Euler, and the second is explicit of La...

Observations of organic material in individual marine particles at Cape Grim during the First Aerosol Characterization Experiment (ACE 1)

During the First Aerosol Characterization Experiment (ACE 1) field campaign in November and December 1995, the particle analysis by laser mass spectrometry instrument was used to measure the composition of ambient particles in situ at Cape Grim, Tasmania, under various conditions ranging from clean marine air to moderately polluted air. Internal mixtures of sea‐salt compounds and organic species were detected in over half of the negative spectra during clean marine conditions and in about 62% of the negative spectra during polluted conditions. In clean marine air masses, aerosol organics appeared to have two distinct source mechanisms depending on the extent of aerosol aging. Organic peaks had a positive trend with sodium sulfate peaks, indicating that organics and excess sulfate may accumulate in aged marine aerosol particles by similar mechanisms. When the sodium sulfate content was low, iodine had a positive trend with organics, which is consistent with organics and iodine originating from the surface‐active layer of the ocean and becoming incorporated into fresh marine particles by bursting bubbles. Based on limited laboratory calibrations, the average organic mass is estimated to be of the order of 10% of the sea‐salt content and is consistent with some of the missing mass fraction for Cape Grim particles (S. Howell et al., manuscript in preparation, 1997), which is the measured difference between gravimetric and ionic mass.

Hydrocarbons, sterols and alkenones in sinking particles in the Indian Ocean sector of the Southern Ocean

Abstract Hydrocarbons, sterols and alkenones were analyzed in samples collected from a 10 month sediment trap time series deployed in the Indian Ocean sector of the Southern Ocean. Fluxes and within-class distributions varied seasonally. During higher mass and organic carbon (OC) flux periods, which occurred in austral summer and fall, fresh marine inputs were predominant. Vertical fluxes were most intense in January, but limited to one week in duration. They were, however, low compared with other oceanic regions. In contrast, low mass and OC flux periods were characterized by a strong unresolved complex mixture (UCM) in the hydrocarbon fraction and a high proportion of stanols as a result of zooplanktonic grazing. Terrigenous inputs were not detectable. The alkenone compositions were consistent with previous data on suspended particles from Antarctic waters. However, U37K′ values diverged from the linear and exponential fits established by Sikes, E. L. and Volkman, J. K. Calibration of alkenone unsaturation ratios (U37K′) for paleotemperature estimation in cold polar waters. Geochimica et Cosmochimica Acta, 1993, 57, 1883–1889], in the low temperature range. The seasonal pattern of alkenone production implied that IPT (integrated production temperature) is likely to be strongly imprinted by austral summer and fall SST (sea surface temperature).

Automated systems for identification of heterotrophic marine bacteria on the basis of their Fatty Acid composition

The fatty acid methyl ester composition of a total of 71 marine strains representing the genera Alteromonas, Deleya, Oceanospirillum, and Vibrio was determined by gas-liquid chromatographic analysis. Over 70 different fatty acids were found. The predominant fatty acids were 16:0, 16:1 cis 9, summed-in-feature (SIF) 4 (15:0 iso 2OH and/or 16:1 trans 9) and SIF 7 (18:1 cis 11, 18:1 trans 9, and/or 18:1 trans 6) for all the strains considered, but minor quantitative variations could be used to distinguish the different genera. In addition to a conventional statistical processing method to analyze the data and draw comparison between species and genera, an approach involving neutral network-based elaboration is applied. The statistical analysis and dendrogram representation gave a comparison of the species considered, while the neural network computation provided a more accurate assignment of species to their genera. Moreover, by using neural networks, it was possible to conclude that only 22 fatty acids were important for the identification of the marine genera considered. A database of Alteromonas, Deleya, Oceanospirillum, and Vibrio fatty acid methyl ester profiles was generated and is now routinely used to identify fresh marine isolates.

Sources and chemistry of PM 10 aerosol in Santa Barbara County, CA

PM 10 aerosols were collected during 1989 every sixth day at six sites in Santa Barbara County, CA. Samples were analyzed for sulfate, nitrate, and ammonium ions, carbon, and elements. Chemical Mass Balance (CMB) receptor modeling was conducted to determine the sources of PM 10 . Motor vehicles, road dust, and marine aerosol accounted for 30–42, 25–27, and 18–23% of PM 10 , respectively, at three urban sites: Santa Barbara, Santa Maria, and Santa Ynez. The marine contribution was 55–63% of PM 10 at two marine background sites. Fresh marine aerosols were characterized by low levels of urban emissions, low concentrations of secondary sulfate and nitrate, and generally higher levels of acidity. Conversely, marine aerosols aged by contact with land-based emissions had higher concentrations of secondary ammonium sulfate and nitrate.

Changes in carbohydrate metabolism of Pila globosa in response to crustacean hyperglycemic hormone.

Hyperglycemia was caused in the snail Pila globosa by the injection of the hyperglycemic hormones obtained from fresh water crabs (Oziotelphusa senex senex) and marine tiger prawns (Penaeus monodon). Tissue glycogen and total carbohydrates presented a significant decrease which indicated that the source of hyperglycemia was the tissue carbohydrates. The hyperglycemic principles also increased the tissue phosphorylase activity and provided evidence for a possible action of the crustacean hyperglycemic hormones in non-arthropod species.

Monitoring the progress of attempts to reduce nutrient load and inputs of certain compounds in the north sea by 50%

During the winter period an inverse linear relation is found between the concentration of dissolved nutrients (phosphorus and nitrogen) and salinity in the Dutch coastal zone. This indicates a conservative behavior of these compounds from the river, through the estuary to the sea. During summer this relation is much more scattered because of biological processes. The physical and statistical properties of the relationship between salinity and the concentration of dissolved inorganic phosphorus and nitrogen are used to calculate when, where, and how many samples have to be taken in order to monitor a reduction of a compound accurately. It appeared that at any given salinity in the estuary and in the sea, the winter period is the most suitable season to detect a reduction of a given dissolved compound. The higher the salinity in the estuary, the more samples are required to prove the reduction significantly. A reduction of only 10% cannot even be demonstrated by field measurements during summer at salinities above 25. It is concluded that one cruise from the river to the sea, covering the salinities from 0 to 35 during the winter period, aimed at establishing the relationship between the concentration and salinity by taking samples at a salinity interval of for instance 1%, is sufficient to monitor a wide-ranging reduction of 10%–50% in both the fresh water and marine water. This program must be combined with a sampling at a salinity of 0, directed to determine the riverine temporal variability.

海産生鮮魚介類を対象とした赤痢菌検査法の検討

Recovery experiments of Shigella strains from fresh marine fish and shellfishes, including fresh sea urchin, which have been artificially contaminated with the strains, were performed using the improved Shigella broth-enrichment method and the culture method reported by Mehlman et al. All of the 43 Shigella stock cultures strains tested were recovered easily by the enrichment method from sea urchin individuals inoculated with a small number of viable cells of each strain. That is, a total of 24 strains (56%) were recovered from sea urchin individuals inoculated with less than 10 viable cells per one individual, and the other 19 strains were also recovered when 10 to 1,000 cells of each strain were inoculated. Recovery of Shigella strains from fish and shellfishes by the enrichment method was hardly affected by the number of contaminated bacteria (SPC, standard plate counts) in these materials. In order to confirm reliability of the enrichment method, similar experiments were performed using S. flexneri strain B as the inoculum and more fish and shellfishes as the samples (24 specimens of fresh sea urchins, 11 specimens of fresh oysters and 5 other specimens including prawns). Except for one oyster specimen which showed an especially high SPC value, the inoculum was able to be recovered from most of the materials inoculated with less than 10 viable cells, and all of the tested samples became Shigella positive when they were inoculated with up to 1,000 viable cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Loss of calcareous microfossils from sediments through gypsum formation

Abstract Laboratory experiments with fresh marine sediments demonstrate the dissolution of calcareous microfossils (foraminifers) and the production of “authigenic” gypsum. Slow oxidation of iron sulfide in the presence of oxygen drives the following reactions: 1. (1) 4FeS + 9O2 + 6H2O = 4FeO(OH) + 4SO2−4 + 8H+ or 2 FeS 2 + 7 1 2 O 2 + 5 H 2 O = 2 FeO ( OH ) + 4 SO 2− 4 + 8 H + 2. (2) H+ + CaCO3 = Ca2+ + HCO−3 3. (3) Ca2+ + SO2−4 + 2H2O = CaSO4·2H2O Three-month experiments resulted in minor to total dissolution of different species from estuarine and open ocean sediments. Elphidium ustilatum was the most resistant to dissolution whereas Elphidium subarcticum was the first species to disappear completely. Agglutinated foraminifers are nearly completely destroyed largely because of bacterial decay of the test binding agent. Loss or partial loss of species may occur either in conditions of storage after collection or because of changing environmental conditions (primarily oxygen levels) at the sediment—water interface.

Spatial distribution of catecholaminergic cells in the fish retina.

The cell density, distribution pattern, and morphology of catecholaminergic (CA) cells have been studied by fluorescence microscopy of retinal flat-mounted preparations from various species of fresh water, estuary, and marine is lowest in the central region surrounding the optic disc, slightly higher in the intermediate region, and highest in the periphery. The size of CA-cells is smaller the higher their density. Following administration of L-Dopa, dompamine, or noradrenaline, the density of CA-cells approximately doubled, due to the appearance of small fluorescent cells. CA-cells are arranged in rows along radial lines which fan out from the optic disc. In large cells of the central and intermediate regions three to five processes arise from the some and extend and ramify irregularly in the inner plexiform layer, while in small cells from the intermediate and peripheral regions two processes arise from opposite poles and extend regularly in a direction perpendicular to the rows of cells and parallel to the retinal margin. In the retina of the marine fish Holocentrus sp CA-cells are fewer in number compared to other fish studied and their processes extend without any regular pattern. In the toad their size and density are homogenous throughout the retina, and their processes show a regular arrangement.

Observations on the particulate chlorine distribution in the Houston-Galveston area

Abstract The chlorine component of total suspended paniculate (TSP) measured in the Houston-Galveston area during 10 days in June and September, 1975 has been examined for spatial variation and correlation with wind speed. The background concentrations of chlorine vary over an order of magnitude (from 0.2 to 6.6 μg m −3 ), and are found to depend on wind speed and direction. Higher background concentrations are associated with inland penetration of fresh marine air from the Gulf of Mexico. These background [Cl] variations are taken into account in order to identify anthropogenic [Cl] sources. Significant non-marine sources of [Cl], located in the industrialized Pasadena-Houston Ship Channel area, are evident in our data.

Examination of the Elutriate Test, a Screening Procedure for Dredging Regulatory Criteria

Water quality parameters were considered in a series of tests, including the Standard Elutriate Test designed to appraise the elutriate techniques. Both the conditional stability constant and the complexing capacity of the elutriate were greater than those of background waters. Although the concentration of the Standard Elutriate can be greater than 1.5 times the original concentration for the four heavy metals considered (Zn, Hg, Pb, Cd), it may be still less than the standards for drinking water and fresh water or marine aquatic life. Thus, such releases themselves should not significantly affect the water quality. It appears that improvement of the existing dredging regulatory criteria concerning Hg, Pb and Zn is desirable. On the other hand, our tests indicate that the release of phosphorus can be large and might significantly affect the water quality in actual open water disposal. It is suggested, therefore, that further research be performed to elucidate the behaviour of phosphorus release from dredged spoils, and that the concentrations of phosphorus and other constituents in the elutriates be compared to the standards. Finally, it is suggested that an acceptable test should realistically reflect the occurrence at the disposal site and consequently, should at least incorporate an estimated resulting sediment-water ratio and a mixing process representative of the dump site.

A Staged Fracturing Treatment for Multisand Intervals

A fracturing method, devised for effectively stimulating massive formations containing many individual sand lenses, has been used to stimulate about 450 wells completed in Eocene-age reservoirs in Venezuela. The method has made possible the development of otherwise uneconomic low-permeability reservoirs. Introduction The producing acreage owned by Creole Petroleum Corp. in the Lake Maracaibo area of Venezuela is situated in the Bolivar Coastal field. The field is approximately 57 miles long from the northern to the southern limit and 52 miles across at its widest point. Creole's leases - about 220,000 acres underlying Lake Maracaibo - and the total area leased before 1971 are shown in Fig. 1. Lake Maracaibo is a body of shallow, brackish water approximately 100 miles long and 70 miles wide. The maximum depth is about 100 ft, and the average depth is about 60 ft. The important reservoir rocks in the Bolivar Coastal field are those deposited during the Miocene, Eocene, and Cretaceous ages. Of these reservoir rocks, only the Eocene formations are of interest in this discussion. The Eocene section (see Fig. 2) consists of about 8,500 ft of alternating well cemented sandstones, siltstones, and shales of fresh, brackish, and shallow marine deposition. The Eocene formations are separated from the overlying Miocene formations by a major unconformity. Sands in the Misoa section of the Eocene are designated as the B-1-X through B-9-X sands. Fault blocks within these sands are termed "reservoirs" and given the designation B-1-X.1, B-1-X.2, etc. The B-1-X through B-5-X reservoirs, which we refer to as the "Upper Eocene Reservoirs," normally have average permeabilities of about 10 md. The total gross thickness of the productive reservoirs is 500 to 600 ft, of which 15 to 20 percent is sand. Because of the relatively low formation permeability and the heterogeneous nature of the reservoir, development could not be justified without stimulation to increase production rates. The fracturing technique used to effectively stimulate the Upper Eocene reservoirs is described in this paper. Included are details of the design and paper. Included are details of the design and execution of the treatment, a comparison of theoretical and observed stimulation ratios, average production data for all treatments, and a comparison of results obtained with different staging techniques. Reservoir Description The Upper Eocene reservoirs consist of a series of sand bodies that were deposited in a shallow marine environment and represent transgressive offlap from the northeast. Because of the depositional environment, these sands consist of many lenticular, low-permeability stringers interbedded in massive shale sections. The individual stringers are generally thin and cannot be correlated from well to well. The B-2-X sands are typical of the Upper Eocene reservoirs and will be discussed for illustrative purposes These sands increase in depth from about 3,500 purposes These sands increase in depth from about 3,500 ft at the north end of the reservoir to about 6,500 ft at the south end. As previously stated, reservoir properties are very heterogeneous. properties are very heterogeneous. JPT P. 897

Diurnal Variation of Aerosol Trace Element Concentrations In Livermore, California*

Concentrations of 15 atmospheric aerosol trace elements in Livermore, California, were measured by neutron activation analysis in 2–hour filter samples for 58 hours during 3 typical summer days. All elements showed cyclic patterns with concentration variations of factors of 3 to 10. Three basic patterns were seen: (1) Na and Cl in phase with each other and nearly perfectly out of phase with the others, with a late night maximum for both; (2) All other elements except Br, showing a midafternoon maximum; and (3) Br, which had morning and evening peaks suggestive of automotive sources. Details of the patterns suggest a diurnal circulation model for the Livermore Valley involving alternation between fresh and aged marine air. Comparison of the trace element patterns with those of CO, NO2, and “oxidant” was not definitive.

High-Pressure Compaction Studies and Chemistry of Solutions Squeezed Out of Muds at Different Stages of Compaction: ABSTRACT

Remaining moisture content (% dry basis) was determined for various clays (montmorillonite, hectorite, illite, kaolinite, dickite, halloysite), marine mud, and soil samples and plotted versus the logarithm of pressure (up to 500,000 psi.). The straight-line relation at pressures above 40-1,000 psi. (depending on type of clay) suggests that compaction is more or less a simple continuous process in the pressure range studied. The resistance to compression apparently increases with higher packing density and more strongly coalesced structures. Most of the water is squeezed out during a relatively short period of time (1-4 days), and equilibrium is reached after about 7-60 days (depending on type of clay). The calculated (from water loss) permeability of clay at high overburd n pressures (15,000-400,000 psi.) is in the order of 10-10-10-13 darcys, values characteristic of nearly impervious soils. Consequently, compaction appears not to be limited by low permeability, but rather by resistance to grain deformation. The salinity of squeezed-out solutions (using fresh marine mud, various types of clay, and sea water) progressively decreases with increase in overburden pressure. Consequently, mineralization of interstitial solutions in shale should be less than that of waters in associated sandstone. Reliable results in determining the chemistry of interstitial solutions of marine mud require that nearly all fluid be squeezed from each sample and require pressures in the 150,000-400,000 psi. range. Experiments concerning X-ray analysis of compacted clay for deciphering the magnitude of overburden pressure were inconclusive. End_of_Article - Last_Page 608------------

The Structure of Cilia, Especially in Gastropods

Next article FreeThe Structure of Cilia, Especially in GastropodsLeonard W. WilliamsLeonard W. Williams Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 41, Number 489Sep., 1907 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/278835 Views: 180Total views on this site Citations: 7Citations are reported from Crossref PDF download Crossref reports the following articles citing this article:Jeremy F. Reiter, Keith Mostov Vesicle transport, cilium formation, and membrane specialization: The origins of a sensory organelle, Proceedings of the National Academy of Sciences 103, no.4949 (Dec 2006): 18383–18384.https://doi.org/10.1073/pnas.0609324103 Bibliography, (Jan 1962): 91–160.https://doi.org/10.1016/B978-0-08-009623-0.50030-1Alfred M. Lucas Coordination of ciliary movement. I. Methods of study and the relation of ciliary coordination to ciliary inhibition, Journal of Morphology 53, no.22 (Jun 1932): 243–263.https://doi.org/10.1002/jmor.1050530203Wilhelm Ludwig Zur Theorie der Flimmerbewegung (Dynamik, Nutzeffekt, Energiebilanz), Zeitschrift für vergleichende Physiologie 13, no.33 (Sep 1930): 397–504.https://doi.org/10.1007/BF00338171D. Atkins On Abnormal Conditions of the Gills in Mytilus edulis . Part I. On Permanent Natural Reversal of the Frontal Cilia on the Gill Filaments of Mytilus edulis, Journal of the Marine Biological Association of the United Kingdom 16, no.33 (Oct 2009): 919–970.https://doi.org/10.1017/S0025315400073148 The mechanism of ciliary movement, Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character 93, no.650650 (Jan 1997): 104–121.https://doi.org/10.1098/rspb.1922.0007O. P. Dellinger The cilium as a key to the structure of contractile protoplasm, Journal of Morphology 20, no.22 (Jul 1909): 171–210.https://doi.org/10.1002/jmor.1050200202