Showing papers in "Marine Chemistry in 1997"

TL;DR: In this paper, surface sediments, collected in the Gironde estuary during February and October 1993, were analysed for polycyclic aromatic hydrocarbons (PAHs) and the aromatic fractions were separated by liquid chromatography of the extracts and analysed by gas chromatography/mass spectrometry (GC/MS).

TL;DR: In this paper, the authors developed a numerical model to make quantitative predictions of dissolved iron concentrations from place to place, based on measured or estimated values of the carbon export flux, are in remarkable agreement with the observed profiles at all stations from the North Atlantic through the Southern Ocean to the North Pacific.

TL;DR: In this article, the authors adapted the "ammonia diffusion" method of nitrate extraction for natural-abundance level nitrogen isotopic measurement of oceanic nitrate, and characterized the blanks inherent in this method and designed a protocol to minimize them.

TL;DR: In this paper, the average C:N ratios of particulate organic matter (POM) and high-molecular-weight dissolved organic carbon (DOM) were 7.7 and 16.7, respectively.

TL;DR: In this article, concentrations of dissolved Y and rare-earth elements (REE) are reported for oxic eastern Mediterranean seawater from the western Levantine Basin, and for anoxic hypersaline brine and overlying oxic seawater in the Tyro sub-basin, the latter data allowing a comparative study of Y and REE behaviours during redox-cycling.

TL;DR: In this article, a segmented flow analysis was used for routine determination of ammonia in sea and estuarine waters, based on the reaction of ammonia with orthophtaldialdehyde (OPA) and sulfite.

TL;DR: In this article, a spectrophotometric method is described for the determination of dissolved mono- and polysaccharides in seawater, based upon the well known alkaline ferricyanide reaction, but uses the reagent 2,4,6-tripyridyl-s-triazine (TPTZ) to give a strongly colored complex with the reduced iron.

TL;DR: The Moss Landing data compares well with less extensive data from at least four other labs; it appears that the community begins to agree on the distribution of iron in the ocean.

TL;DR: In this paper, surface microlayer samples were collected using a stainless steel screen, along with subsurface bulk seawater, and were analyzed for low-molecular-weight (LMW) carbonyl compounds, including formaldehyde, acetaldehyde, propanal, glyoxal, methylglyoxal and pyruvic acid.

TL;DR: In this paper, the role of colloidal organic matter in regulating the estuarine behavior of trace contaminants is examined, focusing on one aspect of the problem: the partitioning of contaminants between organic and inorganic particles, colloids and solution.

TL;DR: The diagenetic behavior of anthropogenic mercury accumulated in sediments of the Saguenay Fjord (Canada) was investigated in this article, where box-cores taken along its main axis and in the St. Lawrence estuary were analyzed for bulk sediment and porewater total and methyl-mercury concentrations as well as a number of other chemical variables.

TL;DR: In this article, the authors explored various procedures for hydrolyzing combined sugars, which would be compatible with highperformance anion-exchange chromatography and pulsed amperometric detection (HPLC-PAD).

TL;DR: In this paper, the authors derived a model that simulates inorganic carbon diffusion and reactions in the vicinity of phytoplankton cells, where carbon uptake is balanced by both diffusional transport across and chemical reactions within the depleted boundary layer.

TL;DR: In this article, a method for the preparation of 2-nitrophenylhydrazide derivatives of low-molecular-weight organic acids in aqueous samples and their subsequent analysis via HPLC with absorbance detection is described.

TL;DR: For the Pomeranian Bight of the Baltic Sea the influence of riverine POM is clearly reflected in the isotopic ( δ 15 N, δ 13 C ) signature of suspended matter and surface sediments as discussed by the authors.

TL;DR: In this article, colloidal organic matter (COM) was isolated using cross-flow ultrafiltration and subsequently characterized for its elemental (C, N, and S) and isotopic (13C and 14C) composition.

TL;DR: In this article, the authors infer that 13C-depleted methane is generated near the top of the methanogenic zone when carbon of 13Cdepleted ΣCO2, produced by microbially-mediated anaerobic methane oxidation, is recycled back to methane through CO2 reduction.

TL;DR: Analysis of the data indicates that a clearer separation of the geochemical sources can be seen with the sterols and suggests that the fatty alcohol provide more information on secondary processes rather than primary origins.

TL;DR: In this paper, the authors measured the mercury speciation and partition in two macro-tidal estuaries, the Loire and the Seine, during several cruises covering various hydrological conditions.

TL;DR: In this paper, the authors improved the analytical methods for determining iron in seawater, based on the established procedure, and carried out fundamental studies for chemical speciation of iron The blank value of the system used was ∼ 005 n M and the detection limit (3 SD) was 001 n M.

TL;DR: The results of the ICES Intercomparison Exercise for nutrients in seawater as discussed by the authors indicated that systematic (particularly relative) errors are widespread, and that many procedures deviate from optimal operating conditions.

TL;DR: In this paper, it was shown that hydrogen peroxide decomposition in natural seawater appears primarily mediated by microorganisms less than 1μm diameter, especially the prokaryotes Vibrio pelagius and Synechococcus sp.

TL;DR: In this paper, water samples collected along the Scheldt estuary during several cruises were analysed for fundamental physico-chemical parameters and for dissolved and particulate trace metals (Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn).

TL;DR: In this paper, three independent, but not mutually exclusive, models are presented to explain these time-varying SRP concentrations: (1) convective mixing; (2) atmospheric deposition; and (3) upward P flux.

TL;DR: Wang et al. as mentioned in this paper used a silica gel crystal growth technique to produce pyrite under conditions approximating those commonly occurring in anoxic marine sediments, and found that the presence of marine organic matter (freeze-dried plankton) caused an increase in the sulfidization rate of goethite and a major decrease in the rate of Pyrite formation.

TL;DR: In this article, the position of the fluorescence maximum and the apparent fluorescence efficiency (A.Fl.E) were measured during estuarine mixing of waters in different European estuaries.

TL;DR: In this article, the authors made observations of N2O concentrations and of the dual stable isotopic composition of n2O in the eastern tropical North Pacific (ETNP) and the Arabian Sea and determined across the oxic/suboxic boundaries that occur in the water columns of the ETNP and Arabian Sea.

TL;DR: In this article, elemental and molecular organic matter concentrations were analyzed in sediments from the Lower St. Lawrence Estuary and the Saguenay Fjord in order to evaluate the historic evolution of pulp and paper mills solid-waste inputs in the system in the last decades and the relative reactivities of lignin and bulk organic materials in coastal sediments.

TL;DR: In this paper, a simple and fast method to measure dissolved total reducible iodine in natural waters using cathodic stripping voltammetry is presented, where Iodate is promptly reduced to iodide by ascorbic acid (0.5 mM) at pH ≤ 2.7, and total iodine is measured as iodide.