This paper aims at assessing the concentrations of heavy metals and the isotopic composition of lead 210Pb in different fractions of sediment produced in the watershed that makes up the Mãe d'água dam and thus characterizing the distribution of metals along the sedimentary column and inferencing in the urbanization of the same process. Sample collection was carried out in June 2014; eight sedim...

This paper introduces a radiographic system for imaging marine sedimentary structures in situ, as an alternative to the currently used intrusive and tedious process of imaging extracted core samples in the laboratory. The system consists of a small isotopic source and a film incorporated into a device that can penetrate the sediment. The design of the device is introduced, and the results of mo...

1. Nutrients released from lake sediments can influence water column nutrient concentrations and planktonic productivity. We examined sediment nutrient release [soluble reactive phosphorus (SRP) and ammonia (NH4 )] at two sites in a eutrophic reservoir (Acton Lake, OH, U.S.A.) that differed in physical mixing conditions (a thermally stratified and an unstratified site). 2. Sediment nutrient rel...

Perfluorinated compounds (PFCs) were detected in sediment core samples collected in Tokyo Bay to reveal their time trends. The core sample deposited during 1950s-2004 was divided into two- to three-year intervals and the concentrations of 24 types of PFCs were determined. Perfluorooctane sulfonate (PFOS) decreased gradually from the early 1990s and its precursor decreased rapidly in the late 19...

Low-temperature fluid flow has been identified as an important component of the heat, mass and chemical flux at sites of active venting. One way to study the movement of water through hydrothermal deposits is to analyse the pore-fluids extracted from sulfidic sediments. The composition of diffuse flow fluids in one sediment core from the south of the active TAG mound reflects the dilution of hi...

Desulfurivibrio alkaliphilus strain AHT2(T) is a strictly anaerobic sulfidogenic haloalkaliphile isolated from a composite sediment sample of eight hypersaline alkaline lakes in the Wadi al Natrun valley in the Egyptian Libyan Desert. D. alkaliphilus AHT2(T) is Gram-negative and belongs to the family Desulfobulbaceae within the Deltaproteobacteria. Here we report its genome sequence, which cont...

Community composition of the infaunal bivalve fauna of the St. Lucie Estuary and southern Indian River Lagoon, eastern Florida was sampled quarterly for 10 years as part of a long-term benthic monitoring program. A total of 38,514 bivalves of 137 taxa were collected and identified. We utilized this data, along with sediment samples and environmental measurements gathered concurrently, to assess...

A mixing model derived from first principles describes the bulk density (BD) of intertidal wetland sediments as a function of loss on ignition (LOI). The model assumes that the bulk volume of sediment equates to the sum of self-packing volumes of organic and mineral components or BD = 1/[LOI/k1 + (1-LOI)/k2], where k1 and k2 are the self-packing densities of the pure organic and inorganic compo...

Lake Sapanca, which is located on the Sakarya-Sapanca-İzmit corridor in NW Turkey, is a freshwater lake with numerous fish farms in its catchment. Palynological analyses including non-pollen palynomorphs of a short (38.5 cm) and a longer sediment core (586 cm), taken in the centre of the lake and dated in previous investigations, revealed the presence of brackish and marine palynomorphs. The lo...

In a study of a sediment core from the US Atlantic Coastal Plain (Ocean Drilling Program Site 174X-Millville), Wright and Schal-ler (1) claim to have resolved the onset of the Paleocene/Eocene carbon isotope excursion (CIE) across 13 y. Such a rapid change would require an enormous and instantaneous release of isotopically light carbon into the ocean/atmosphere, implicating comet impact. The cl...