The morphology of passive continental shelves is dictated by the input of sediments from rivers and their redistribution by waves, currents, and gravity-driven flows. The pathways followed by sediments sculpt a landscape whose diversity is rarely matched on Earth’s surface. Sediments are released to the shelf from triangularly shaped, elongated, and dendritic deltas. Barrier islands rise from g...

The aim of this study was to assess heavy metals mobility and toxicity in sediments collected from a dam reservoir in the conditions of intensive human impact by using chemical fractionation and a battery of bioassays. In the studies, the test organisms were exposed to substances dissolved in water (Microtox, Phytotestkit) as well to substances absorbed on the surface of solid particles (Phytot...

Interaction between herbicides and sediments in water systems is an important process occurring in water, which influences the behaviour of the herbicides in water. This paper reports on the sorption of herbicides norflurazon, oxadiazon and trifluralin on soil and the interaction between the herbicides and sediments under stirred and non-stirred conditions. The sorption coefficients of the herb...

Several bacteria-based assays, notably Vibrio fischeri luminescence assays, are often used as environmental monitoring tool for toxicity in sediments that may serve as both sinks and secondary source of contamination in aquatic ecosystems. In this study, we used 30-s kinetic bioassays based on V. fischeri to evaluate the toxicity associated to sediments from five localities with different conta...

The phosphate sorption capacity of intertidal vegetated marsh sediments was measured along a salinity gradient in the Cooper River estuary, South Carolina. The phosphate sorption capacity of the surface sediments (0–10 cm) of a freshwater marsh was higher than the sorption capacity of sediments from brackish and saline marshes, and surface sediments had greater sorption capacity than subsurface...

Platinum contamination in estuarine and coastal sediments has been evaluated in three cores collected from the Tagus Estuary and Prodelta shelf sediments. Elevated concentrations, up to 25-fold enrichment compared to background values, were found in the upper layers of the estuarine sediments. The degree of Pt enrichment in the estuarine sediments varied depending on the proximity to vehicular ...

NO(3) concentration profiles were measured in the sediments of a meso-eutrophic lake with a newly developed microelectrode. The depth of penetration of NO(3) varied from only 1.3 mm in organic-rich profundal silty sediments to 5 mm in organic-poor littoral sandy sediments. The thickness of the zone of denitrification in the organic-rich sediments was <500 mum. Oxygen profiles measured simultane...

This work is undertaken to develop a methodology to enhance the management of dredged marine an the North of France. The main objective of this study is to determine the main characteristics of these sediments. In this order, physical, mineralogical and chemical properties of both types of sediments are measured. Moreover, their potential impacts on the environment are assessed throughout leach...

Chlorophyll degradation products are preserved in marine sediments over timescales of thousands of years. The production of chlorophyll in the water column is related to biological productivity, so chlorophyll degradation products (chlorins) preserved in marine sediments can be used as indicators of paleoproductivity. A new, rapid, nondestructive method of determining chlorin concentrations in ...

Sediments tell a tsunami story Trying to understand where major earthquakes and tsunamis might occur requires analysis of the sediments pouring into a subduction zone. Thick sediments were expected to limit earthquake and tsunami size in the Sumatran megathrust event in 2004, but the magnitude 9.2 earthquake defied expectations. Hüpers et al. analyzed sediments recovered from the Sumatran megat...