Showing papers in "Marine Chemistry in 1999"

TL;DR: The importance of underground estuaries in coastal aquifers has been emphasized by the use of chemical tracers in the coastal ocean as mentioned in this paper, which can be used to evaluate the importance of these unseen estuars in supplying not only chemical tracer, but also nutrients, to coastal waters.

TL;DR: In this paper, a comparison of black carbon based on thermal oxidation and hot concentrated nitric acid pretreatments revealed that the latter significantly overestimates combustion derived carbon phases, and that black carbon accounts for about 15 to 30% of total organic carbon and therefore reduces the fraction of sedimentary organic carbon.

TL;DR: In this article, the authors collected sediment cores from San Francisco Bay (SFB) and one sediment core in Tomales Bay (TB), a reference estuary, and determined the concentrations of Ag, Al, Cr, Cu, Fe, Hg, Mn, Ni, Pb, V and Zn.

TL;DR: The optical properties of the Orinoco River plume were investigated during two cruises to the eastern Caribbean using absorption and fluorescence spectroscopy as mentioned in this paper, and it was found that high concentrations of dissolved organic carbon and abundance of colored dissolved organic matter (CDOM) in the Eastern Caribbean were related to the discharge of the river.

TL;DR: In this article, cross-flow ultrafiltration studies were carried out in the Trinity river estuary of Galveston Bay in July, 1993, May, 1994 and July 1995 to study the phase speciation for a number of metals (e.g., Cd, Cu, Co, Fe, Ni, Pb, Zn) in estuarine waters.

TL;DR: In this paper, the authors studied the biogeochemical cycling of Hg in the Chesapeake Bay and its tributaries, including sampling transects into Baltimore Harbor, a region where sediment Hg concentrations can exceed 5 nmol g−1 and sediment MMHg concentrations approach 50 pmolg−1.

TL;DR: In this article, a brief review of the possible ramifications of organic-mineral interactions for estuaries, using the well-studied Amazon River/Estuary system as an example, is presented.

TL;DR: In this paper, the Fly and Sepik rivers of Papua New Guinea (PNG) were studied and the degree to which river input and estuarine reactions affect the rare earth element (REE) composition of surface sea water in the western tropical Pacific Ocean.

TL;DR: Fluorescence of dissolved proteinaceous materials was examined in two estuaries differing primarily in river input as mentioned in this paper, and low-wavelength excitation (220-230 nm) was found to be more useful than the high wavelength excitations (280 nm) usually reported in the literature.

TL;DR: In this paper, the authors used a new thermodynamic model to compute the barite saturation index of ocean waters, mainly from GEOSECS data, and showed that equilibrium between barite and seawater is reached in a number of places: cold surface waters of the Southern Ocean, waters at intermediate depths (2000-3500 m) in the Pacific, deep waters (2000 -3500m) of the Gulf of Bengal.

TL;DR: Sediment chronologies based on radioisotope depth profiles were developed at two sites in the San Francisco Bay estuary to provide a framework for interpreting historical trends in organic compound and metal contaminant inputs as discussed by the authors.

TL;DR: In this paper, sediment cores collected from Richardson and San Pablo Bays in San Francisco Bay were used to reconstruct a history of polycyclic aromatic hydrocarbon (PAH) contamination.

TL;DR: In this paper, a radiochemical technique was used to investigate the photoreduction of gaseous mercury in the presence of humic substances and showed that the reaction rate increased with humic concentration and presence of light.

TL;DR: In this article, the authors traced aluminum sulfide mineral aerosol (dust) from its predominant North African source to the Sargasso Sea and derived estimates of the residence time of dissolved and total aluminium, manganese, and iron in the euphotic zone of the sargasso sea.

TL;DR: In this article, a model was developed to help interpret the relative contributions of different end-members to the mixing zones of the Mississippi and Atchafalaya Rivers during 1993 and 1994.

TL;DR: In this paper, the conditional stability constants of metal-sulfide complexes were determined in pH 8 seawater at various salinities, by flow-analysis with detection by cathodic stripping voltammetry (FA-CSV).

TL;DR: In this article, a diffusion-reaction model of the carbonate system (CO2, HCO3−, CO32−, H+, OH−, B(OH)3, B(O)4−) in the microenvironment (the diffusive boundary layer) of living planktic foraminifera is presented.

TL;DR: In this article, the authors investigated the chemical composition of the CO 2 -rich water at Tutum Bay in shallow water along the inner shelf that contains a patchy distribution of coral-algal reefs.

TL;DR: In this paper, the role of surfactant organic matter in marine aerosol production has been studied under conditions in which there is a large coverage of whitecaps on the sea surface.

TL;DR: Loscher et al. as discussed by the authors studied the distribution of iron in the Antarctic Circumpolar Current (ACC) along a north-south transect at ∼89°W and found that dissolved Fe was found at low concentrations ranging from 0.05 nM near the surface to 0.5 nM in deeper waters.

TL;DR: In this paper, rare earth element (REE) determinations have been made on 25 surface seawater samples on a longitudinal transect from Asia to North America within a latitudinal band of 24-32°N.

TL;DR: The degree of atmospheric saturation for O2, Ar, and N2 gases in water can be determined to accuracies of ± 0.1-0.3% using mass spectrometry to determine the gas ratios and Winkler titrations for oxygen analysis.

TL;DR: In this article, the role of surface chemistry in controlling the release of NH4+ from resuspended sediments in the large, shallow, negative estuary Laguna Madre, TX was examined.

TL;DR: In the Laptev Sea, the concentration of dissolved organic matter (DOM) and silicate in the Lena River generated a concentration gradient extending towards the oceanic regions.

TL;DR: In this paper, seawater samples were poisoned with mercuric chloride to assess its suitability for the long-term storage measurement of inorganic nutrients, and the results showed that poisoning with mercury chloride is a suitable method for the storage of in organic nutrients.

TL;DR: In this article, the y-intercept of a plot of the organic carbon retained by a glass-fiber filter against the volume filtered by Niskin® and Go-Flo® bottles was assessed using coastal seawater, and the intercept was approximately two-fold greater than the precombusted filter blank.

TL;DR: In this paper, the authors examined the variation in marine and terrigenous sources of the organic matter during the last 15,000 Cal. yr BP, hydrogen index values, C/N ratios, and specific biomolecules (short- and long-chain n-alkanes, short-chain fatty acids, sterols, alkenones, and pigments) were determined in three sediment cores from the Laptev Sea continental margin.

TL;DR: In this paper, the authors examined how diffusion and chemical reactions in the microenvironment of a phytoplankton cell influence the efficiency of both strategies to increase the bioavailability of iron and to reduce iron stress.

TL;DR: In this paper, the trace element content of marine phytoplankton reflects nutritional status, species composition, surface area to volume ratios, and interactions with bioactive and toxic elements in the ambient seawater.