Ml Of Seawater Research Articles

Sites of release of Putative Sex Pheromone and Sexual Behaviour in FemaleCarcinus maenas(Crustacea: Decapoda)

Pre-moult femaleCarcinus maenasurine was confirmed as a source of putative sex pheromone. The sexual and temporal specificity of bioactivity in pre-moult female urine was demonstrated when urine samples taken from inter-moult and pre-moult male crabs, and inter-moult females, failed to generate a sexual response from receptive males. Detection sensitivity of male crabs to pre-moult female urine was established at a dilution factor of 1μl of urine in 10ml of seawater. Experimental blockage of the site of urine release (the antennal gland opercula) failed to diminish the chemical attractiveness of pre-moult female crabs to test males, implicating at least one further site of putative pheromone release. Observations of female sexual behaviour demonstrated an active role by pre-moult and post-moult female crabs when introduced to male crabs whose locomotor movement had been temporarily restricted.

Chelation ion chromatography as a technique for trace elemental analysis in complex matrix samples

A new method for the determination of lanthanides based on chelation and ion chromatography with absorbance detection is described. γ-Aminobutyrohydroxamate resin or its derivative, N-methyl- γ-aminobutyrohydroxamate resin in a column was used to concentrate and separate lanthanides from the alkali and alkaline earth metals and other matrix components. Various complexing agents were investigated as possible eluants. The influence of a sample matrix and parameters important for quantitative analysis are discussed. Using γ-aminobutyrohydroxamate resin as concentrator, and potassium nitrate (0.02 M) as matrix eliminator, with the mobile phase of oxalic acid (0.03 M, pH 4.5)-diglycolic acid (0.005 M), and 4(2-pyridylazo) resorcinol (6 × 10 −5 M)- ZnEDTA(1 ×10 −4 M) as postcolumn reagent, most of the lanthanides can be separated and determined in the complex matrix samples. The detection limit was found to be 2.5 ng ml −1 for these elements by concentrating 25 ml of sea water.

Life-table evaluation of sediment-associated chlorpyrifos chronic toxicity to the benthic copepod, Amphiascus tenuiremis.

A partial life-cycle experiment was conducted to assess chronic effects of sediment-associated chlorpyrifos, an organophosphate pesticide, on a marine, benthic copepod population. The static-renewal experiment was initiated with 4 treatments including control, 13 replicates per treatment with one female (bearing first clutch of eggs) per replicate. No males were added because one fertilization is sufficient for several clutches. Once weekly, all replicate chamber contents (10-ml culture tubes with 1.5 ml of sediment and 5 ml of seawater) were sieved and enumerated to determine survival and fecundity. Surviving adult females were placed back into chambers with newly spiked sediments. This process was repeated for 7 weeks until all initial females were dead or reproduction had ceased for at least two weeks. Survival and fecundity data were then used to determine population dynamic parameters such as r (intrinsic rate of natural increase) for each treatment. Results revealed a chronic toxicity response with significant population effects (p<0.05) in all pesticide treatments versus the control; concentrations that represent 7-32% of the 96-hr LC50. The control treatment had an r value 26-52% higher than the pesticide treatments. This translated into a control population rate increase of up to twice that of pesticide treatments. In addition, significant reductions in weekly and total fecundity were found in all chlorpyrifos treatments. Based on these results, usage of population parameters with benthic copepods allows for an integrative measurement of population effects from chronic exposure to sediment-associated contaminants.

Studies on the adsorption of trace amounts of beryllium(II) on the surface of silica fibres from an aqueous phase for the development of a novel enrichment technique for electrothermal atomic absorption spectrometry

Trace amounts of beryllium(II) were adsorbed on the surface of silica fibres from a weak alkaline solution. The distribution ratio depended on the pH of the solution; however, a constant value (log D= 5.1) was obtained at pH 9.5 in the concentration range 6.4–220 µmol kg–1 in the silica phase. From the pH versus D curve, it was deduced that the beryllium(II) species adsorbed was (—SiO)Be(OH)2– or (–SiO)2Be(OH)22–. Based on these phenomena a simple enrichment technique was developed for the determination of trace amounts of beryllium(II) by electrothermal atomic absorption spectrometry. A 50–500 ml portion of the sample solution (pH 9.5) containing up to 6 ng of beryllium(II) was passed through a stack of three sheets of silica-fibre filter to collect the beryllium(II), which was then desorbed using three 0.5 ml portions of 0.5 mol l–1 HCl containing 15 mg l–1 of silicon for electrothermal atomic absorption spectrometry. A concentration factor of over 300 was easily attained. The detection limit, based on three times the standard deviation of the blank, was 0.15 ng of beryllium(II) for 500 ml of solution. The method was applied to the determination of beryllium(II) in natural water samples. A quantitative recovery was obtained when 3.0 or 6.0 ng of beryllium(II) were added to 500 ml of sea-water.

Application of flow injection spectrophotometry to the determination of dissolved iron in sea-water

Two flow-injection spectrophotometric procedures have been developed for the determination of trace amounts of iron in sea-water. The first procedure is based on the iron-catalysed oxidation of p-phenetidine by periodate after in-valve separation/preconcentration of iron(III). The limit of detection is 0.05 µg l–1 of iron when concentrating 6 ml of sea-water. The second procedure is based on the selective catalytic effect of iron(III) on the oxidation of N,N′-dialkyl-p-phenylenediamines by hydrogen peroxide. The limit of detection of this method is 0.03 µg l–1 of iron with a sampling rate of 60 h–1. The utility of both flow-injection methods was demonstrated by the determination of dissolved iron in sea-water samples, with an average recovery of 98–110% and an average relative standard deviation of 1.8–8.1%.

Determination of silver in waters and soil by electrothermal atomic absorption spectrometry after complexation and sorption on carbon

A method for the preconcentration of silver is proposed. Silver is complexed by the ammonium salt of dithiophosphoric acid O,O-diethyl ester and sorbed on to carbon. After desorption in a small volume of nitric acid solution, silver is determined by electrothermal atomic absorption spectrometry. In de-ionized water the yield was about 70%, indicating incomplete complexation and/or sorption on the carbon. In purified sea-water (sea-water submitted to solvent extraction to extract silver), the yield was less, about 40%, probably due to the effect of concomitants in the sea-water. The method was applied to sea and river waters and to a soil reference material. Spiked sea-water samples produced an average recovery of 102%, indicating good accuracy if analytical solutions in purified sea-water are used for the calibration. The detection limit (k=3) for 200 ml of sea-water is 0.3 ng l–1. After acid dissolution of the soil sample, ascorbic acid should be added, prior to the complexing agent, to avoid interference of iron(III). Because of the small final volume, high enrichment factors can be obtained.

Determination of cadmium and lead at μg/1 levels in aqueous matrices by chelation ion chromatography

A method for the simultaneous determination of μg/1 or sub-μg/1 levels of cadmium and lead in sea water by chelation ion chromatography is demonstrated. The method consists in the preconcentration of a sea-water sample containing cadmium and lead on an iminodiacetate chelating resin; alkali and alkaline earth metals are removed from the resin with an ammonium acetate buffer, the metals are eluted and separated by cation-exchange chromatography, followed by postcolumn derivatization with 4-(2-pyridylazo)resorcinol and spectrophotometric detection at 520 nm. The concentration and separation steps are automated. The detection limit, when concentrating 200 ml of sea water, was found to be 2 ng for cadmium and 6 ng for lead. Relative standard deviations of 4.5% and 6.8% for 10 μg/1 of cadmium and lead, respectively, were obtained. Transition metals (Fe, Co, Ni, Zn, Cu, Mn) do not interfere in the analysis. An application of the method to the determination of cadmium and lead in sea-water samples collected in the Taranto gulf (Italy) is presented.

Determination of nanomolar concentrations of individual dissolved low molecular weight amines and organic acids in seawater

A concentration technique using diffusion of amines and organic acids across a hydrophobic membrane was developed for the measurement of these compounds in seawater. Using this approach, the amines and organic acids are concentrated from seawater and also are separated from inorganic salts and most other dissolved organic compounds. Amines or organic acids in the concentrated sample are then quantified by gas chromatography. Concentration factors up to 1000 can be achieved. Natural concentrations of amines and most organic acids of 10 nM can be measured in 500 mL of seawater

Rhenium in seawater: Confirmation of generally conservative behavior

A depth profile of the concentration of Re was measured in the Pacific Ocean using a technique we have developed for the clean chemical separation and the precise measurement of Re by isotope dilution and negative thermal ionization mass spectrometry (ID-NTIMS). This technique permits Re concentrations to be determined from 200 mL of seawater with a typical precision of ±5‰. This is an improvement of at least a factor of 100 over the techniques used in previously published determinations of Re in seawater. We obtain a narrow range for Re from 7.20 ± 0.03 to 7.38 ± 0.03 ng/ kg for depths between 45 m and 4700 m. This demonstrates that Re is relatively well mixed throughout the water column and confirms the theoretical prediction that the behavior of Re in the oceans is conservative. When examined in detail, both salinity and the concentration of Re increase by approximately 1.5% between 400 and 4700 m, a correlation consistent with conservative behavior. However, Re appears to be depleted relative to salinity by 1.0–1.5% at 100 m, and enriched by approximately 4% at the surface. These observations suggest a minor level of Re scavenging in near surface waters, and an input of Re to the ocean surface. This work demonstrates the utility of ID-NTIMS for geochemical investigations of certain trace elements that have not previously been amenable to detailed study.

Determination of trace rhenium in sea water by inductively coupled plasma mass spectrometry with on-line preconcentration

An on-line column preconcentration method is decribed for the determination of rhenium in sea water by inductively coupled plasma mass spectrometry. Two dimensions of anion-exchange resin (Dowex-1X8) minicolumn (7 mm × mm i.d. and 14 mm × mm i.d.) were used for the quantitative preconcentration of rhenium in sea water. The concentrated rhenium was eluted from the column with nitric acid. A simple calibration technique with lutetium as internal standard and also isotope dilution were used for the determination of rhenium in sea water. Enrichment factors of 38- or 101-fold were obtained using 10- or 50-ml sea-water samples, respectively, and the relative standard deviations for replicate measurements ( n=3) were 2.62% for natural sea water and 0.34% for synthetic sea water. The detection limits after on-line preconcentration of 10 and 50 ml of sea water were 0.27 and 0.1 pg ml −1, respectively. Almost no contamination blank signal or matrix interferences were observed.

Detection of Gene Expression in Genetically Engineered Microorganisms and Natural Phytoplankton Populations in the Marine Environment by mRNA Analysis

A simple method that combines guanidinium isothiocyanate RNA extraction and probing with antisense and sense RNA probes is described for analysis of microbial gene expression in planktonic populations. Probing of RNA sample extracts with sense-strand RNA probes was used as a control for nonspecific hybridization or contamination of mRNA with target DNA. This method enabled detection of expression of a plasmid-encoded neomycin phosphotransferase gene (nptII) in as few as 10Vibrio cells per ml in 100 ml of seawater. We have used this method to detect expression of the ribulose-1,5-bisphosphate carboxylase large-subunit gene (rbcL) in Synechococcus cultures and natural phytoplankton populations in the Dry Tortugas, Florida. During a 36-h diel study, rbcL expression of the indigenous phytoplankton was greatest in the day, least at night (1100, 0300, and 0100 h), and variable at dawn or dusk (0700 and 1900 h). These results are the first report of gene expression in natural populations by mRNA isolation and probing. This methodology should be useful for the study of gene expression in microorganisms released into the environment for agricultural or bioremediation purposes and indigenous populations containing highly conserved target gene sequences.

Enhancement of Biodegradation of Alaskan Weathered Crude Oil Components by Indigenous Microbiota with the use of Fertilizers and Nutrients

ABSTRACT Bench-scale biodegradability studies of the Alaskan weathered crude oil were undertaken as part of the bioremediation project for the shorelines of Prince William Sound Alaska, contaminated by the Exxon Valdez oil spill. The purpose of the studies was to evaluate the ability of the indigenous microbial consortium of the seawater and island beach areas to biodegrade the weathered crude oil's alkane hydrocarbon and polynuclear aromatic (PAH) constituents in batch-type respirometric reactors and shaker flask systems. Biodegradation studies used Inipol EAP22 and water-soluble nitrogen and phosphorus-containing solution (OECD) as the fertilizer nutrient source. In the respirometric studies, the unpolluted beach material in seawater was spiked with 1,000, 300, and 100 mg/L of weathered crude oil and with Inipol at 5 percent of oil weight or with OECD stock solution concentrates. The contents were brought up to 1,000 mL with seawter. Unpolluted beach material spiked with 10,000, 3,000, and 1,000 mg/L of weathered crude oil and with either Inipol at 5 percent of oil weight or with OECD inorganic salts in 1,000 mL of seawater were used in shaker flask microcosm studies. Temperature of incubation in both studies was 15° C, and culture systems were incubated in darkness. Cumulative oxygen uptake data, growth data, and gas chromatography/mass spectrometry analysis data demonstrate almost complete utilization of the alkane hydrocarbon constituents in the presence of Inipol fertilizer and OECD synthetic medium, and significant biodegradation of the PAH constituents after six weeks of incubation. Control experiments without Inipol or OECD nutrients demonstrated absence of biodegradative activity.

特集 「地球環境および地域環境と化学」 海水中の微量有機スズ化合物の分析ならびにその海洋環境における挙動に関する研究 （第７報） 海水中の微量ジブチルスズおよびトリブチルスズ化合物の定量とその港湾海水中における濃度分布

In order to study the distribution and fate, of butyltin compounds in the marine environment, the concentrations of dibutyltin dichloride (DBTC), tributyltin chloride (TBTC) and tetrabutyltin (TetBT) in seawater collected from several bays were measured. DBTC, TBTC and TetBT at ng/l (ppt) levels in seawater were determined by gas chromatography with flame photometric detection (GC-FPD). DBT and TBT compounds in seawater were hydrogenated to dibutyltin dihydride (DBTH) and tributyltin hydride (TBTH) with sodium borohydride, and simultaneously extracted into dichloromethane. The extract was dried with anhydrous sodium sulfate, and was concentrated to 1 ml on a rotary evaporator at 40°C. The recoveries of DBTC and TBTC added to seawater sample were 87.1-98.4%. The detection limits of DBTC and TBTC using 1000 ml of seawater were 0.01 μg/l and 0.01 μg/l (10 ppt), respectively. Seawater samples (n=62) were collected from Hiroshima Bay (A), Maizuru Bay (B), Murotsu Harbor (C), and Kudamatsu Bay (D) during the period from April 1989 to November 1989 and the distribution of DBTC, TBTC and TetBT in seawater were investigated. The results obtained were as follows:1) The concentrations of butyltin co mpounds in seawater were found to be in the range of N. D. (not detected)-0.40 μg/l for DBTC, N. D. -0.58 μg/L for TBTC and N. D. for TetBT.2) Frequent concentrations of DBTC and TBTC in seawater were in the rang e of 0.010.05 jugg and 0.01-0.05 respectively.3) DBT compound in sea water could be produced by degradation of TBT compound in the marine environmet.4) The concentrations of DBTC and TBTC for Murotsu Harbour (C) were higher than those for Hiroshima Bay (A), Maizuru Bay (B) and Kudamatsu Bay (D). Thus, DBT and TBT compounds were not accumulated in big bays, but in little harbour with relatively poor water exchange.

Bioencapsulation of Therapeutic Quantities of the Antibacterial Romet‐30 in Nauplii of the Brine Shrimp Artemia and in the Nematode Panagrellus redivivus

AbstractNauplii of the brine shrimp, Artemia, and cultures of the soil nematode, Panagrellus redivivus, were fed a suspension of the water‐insoluble antibacterial Romet‐30 (sulfadimethoxine plus ormetoprim) to determine if they could be used as a mechanism for delivery of the drug to larval penaeid shrimp.Romet‐30 was added to groups of brine shrimp nauplii and nematodes in 1 L beakers to achieve a concentration of 3 mg of drug per ml of seawater. After a 4 h uptake period, predetermined numbers of organisms were assayed for antibiotic content using the micro‐plate diffusion method and a Romet‐30 sensitive strain of Vibrio alginolyticus as the indicator. The resulting zones of inhibition were compared to that of a standard Kirby‐Bauer sensitivity disc containing 25 μg of the drug that was placed on each plate as standard control. Negative controls consisted of equal numbers of nauplii and nematodes that were not exposed to the antibiotic. Artemia nauplii and nematodes accumulated approximately 0.1 μg of the drug per nauplius and approximately 0.25 μg per nematode. They exhibited no signs of toxicity from exposure to the drug and contained the antibiotic in sufficient quantity to provide a theoretical therapeutic dose of the drug when fed to penaeid larvae.In subsequent tests, normal and diseased larval Penaeus stylirostris readily accepted Romet‐30 enriched Artemia. Diseased larvae fed the drug in this manner exhibited a statistically greater overall survival and a greater survival to the post‐larval stage by Student's t‐test at the 5% significance level.

Simultaneous multielement determination of trace metals using 10 mL of seawater by inductively coupled plasma atomic emission spectrometry with gallium coprecipitation and microsampling technique

Dosage par cette methode de Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y et Pb avec etalonnage interne utilisant le gallium. La limite de detection pour ces elements varie de 500 (Pb) a 10 ng/L (Cu et Zn). La procedure analytique est simple, puisque environ 50 echantillons peuvent etre enrichis et analyses en 1 heure. La methode a ete appliquee a l'analyse de plusieurs eaux de mer naturelles, elle est particulierement adaptee pour des echantillons de tres faible volume

Rate of Water Admission Through the Madreporite of a Starfish

ABSTRACT Time course studies employing the fluorescent, high molecular weight tracer, fluorescein isothiocyanate dextran, confirm that there is a steady entry of sea water through the madreporite of the starfish, Echinaster graminicola, even under constant environmental conditions. This entry serves to supply replacement fluid to both the water vascular system and the perivisceral coelom, with more going to the latter than the former (10·67 vs 6·35 μl h−1 for a 7·25 g animal). Since nearly 2·4 days may be required for an animal to take up 1 ml of sea water through the madreporite, the rate of entry is too low to be easily seen in direct observation, or to have immediate physiological consequences if prevented. Nevertheless, the rate is probably sufficient to make a substantial contribution to fluid volume regulation, functioning along with osmolyte transport and other processes that have been emphasized in recent literature.

Physiological constraints upon marine organisms

ABSTRACTWhen compared with sea water, most marine invertebrates are isosmotic but show varying degrees of ionic regulation, from accumulation of potassium and calcium to reductions of magnesium and sulphate. A reduction of sulphate in pelagic animals such as jellyfish and salps, and an accumulation of ammonium ions in arrow-worms (Sagitta) contribute to their near-neutral buoyancy. Marked reductions in salinity exclude mahy marine invertebrates. In the Baltic, polychaetes, bivalve molluscs and decapod crustaceans are reduced from 193, ninety-two and sixty-four species in the Belt Sea (salinity S 10-30‰) to three, four and two in the Gulf of Finland (salinity S 5-9‰). The chelicerateLimuluscan stand a wide range in salinity, a few insect larvae can tolerate concentrations of 200% sea water, while the branchiopod shrimpArtemiacan stand crystallising brine (36-37% NaCl). Very few species can tolerate temperatures of 40°C. One such species is the polychaeteAlvinella pompejana,a hydrothermal vent animal at East Pacific Ridge (to the W of S America). The harpacticid copepodTigriopusliving in evaporating rockpools has a lethal temperature of 42°C at a salinity of S 90‰, but at S 8‰ that temperature is 34°C. Lack of oxygen and presence of hydrogen sulphide limit the distribution of animals in certain areas. Most active animals have respiratory pigments in their principal body fluid. Burrowing invertebrates such asArenicolaandLingulahave respectively haemoglobin in the blood and haemerythrin in the coelomic fluid, with mean oxygen capacities of 6 ml O2per 100 ml in each case, compared to 0·6 and 0·5 ml in sea water at 10° and 20°C.

Secretory capacity of the lachrymal salt gland of hatchling sea turtles,Chelonia mydas

The lachrymal salt glands ofChelonia mydas were functional when hatchlings emerged from the nest. Osmotic concentrations up to 720 mosmol kg−1 were recorded in spontaneously produced tears (salt gland secretions). When injected with a Na+ load (1500–2700 μmol (100 g)−1) newly emerged hatchlings produced tears ranging in osmotic concentration from 1000–1900 mosmol kg−1 with Na+ secretion rates from single glands of 200–475 μmol (100 g·h)−1. In these circumstances the rate of sodium excretion, via the salt glands, was equivalent to the sodium content of 0.2 to 0.5 ml of sea water per hour. Since the apparent drinking rate of hatchlings within the first two days of entering sea water was approximately 0.5 to 1.7 ml per day, the excretion of Na+ imbibed by drinking is well within the secretory capacity of the lachrymal salt glands.

Determination of trace elements in sea water by graphite-furnace atomic absorption spectrometry after preconcentration by tetrahydroborate reductive precipitation

A method is described for the preconcentration of 16 elements from coastal and deep ocean sea water based on their reductive precipitation by sodium tetrahydroborate. The enrichment factors obtained were sufficient to permit the analysis of a near-shore sea-water reference material (11 elements) and an open ocean sea-water reference material (9 elements). Recoveries from 900 ml of sea water ranged from 80 to 107% (100-ml sample for Mn) with absolute blanks between <1.0 ng (Se) and 20 ng (Cu). Estimated detection limits varied from 0.3 ng l −1 (Pb) to 19 ng l −1 (As) based on a 36-fold concentration of a 900-ml sample.

Pathogenicity and host specificity of Labyrinthuloides haliotidis (Protozoa: Labyrinthomorpha), a parasite of juvenile abalone

Infections with Labyrinthuloides haliotidis, an achlorophyllous, eucaryotic protist, were lethal to almost all juvenile abalone (Haliotis kamtschatkana and Haliotis rufescens) less than 6 months of age in an abalone mariculture facility in British Columbia, Canada. In laboratory experiments, L. haliotidis isolated from infected abalone or grown in axenic nutrient medium was infective for abalone (H. kamtschatkana) less than 4.0 mm in shell length and 140 days of age. Ten days after exposure to at least 104 parasites in 20 mL of sea water, about 90% of these abalone died with numerous parasites throughout the tissues of the head and foot. By about 190 days of age, regardless of shell size, abalone mortalities were reduced to less than 50% after exposure to about 105 parasites. Finally, by about 340 days of age, most juvenile abalone (4.0 to 10.5 mm in shell length) did not succumb after three consecutive exposures, 13 days apart, to between 2 × 105 and 5 × 106L. haliotidis. Larger abalone (15 to 25 mm in shell length) did not become infected following intramuscular injections of about 1.5 × 104L. haliotidis. Small juvenile scallops (Patinopecten yessoensis) and juvenile oysters (Crassostrea gigas), both less than 8 months of age, were also resistant to infection. However, two of the oysters with badly cracked shells became infected. This suggests that if L. haliotidis can gain access, it is capable of using living oyster tissue as a source of nutrients for growth and multiplication.