The identification of nitrate-nitrogen (NO3–N) origin is important in the control of surface and ground water quality. These are the main sources of available drinking water. Stable isotopes (15N and 18O) for NO3–N and along with a 1-D reactive transport model were used to study the origin and processes that lead to nitrogen transformation and loss in a major stream that flows into a reservoir ...

In recent years growing human pressure on agricultural land in the north of the Lao PDR has led to accelerated degradation processes along hillslopes, and higher sediment delivery rates to streams. Furthermore, high demand from urban centres is attracting farmers to cultivate vegetables in riparian areas. These land-use changes may have negative affects on stream water quality. The aims of this...

Here, we describe the metagenome and functional composition of a microbial community in a historically metal-contaminated tropical freshwater stream sediment. The sediment was collected from the Mina Stream located in the Iron Quadrangle (Brazil), one of the world's largest mining regions. Environmental DNA was extracted and was sequenced using SOLiD technology, and a total of 7.9 Gbp was produ...

This research studied the occurrence of estrogens in the Upper Satilla watershed, Georgia, USA, which was impacted by poultry litter land application and discharge from a sewage treatment plant (STP) receiving poultry wastes. Over 14 months, four estrogens in stream water, sediment, suspended particles, and STP samples were quantified by LC/MS. Estrogens were consistently found in the STP influ...

The effectiveness of four road turn–out ditch treatments (vegetation, rip–rap, sediment fences, and settling basins) in reducing sediment export to the forest floor was evaluated. These four runoff control methods are commonly prescribed to control forest road runoff and sediments. The study utilized runoff samplers, runoff diversion walls, sediment filter bags, and erosion stakes to evaluate r...

Urbanization of a watershed increases impervious area, and consequently increases stormwater runoff. When left uncontrolled, these increases in stormwater runoff cause downstream flooding, accelerate channel erosion, and impair aquatic habitat. Increases in the magnitude and duration of stormwater runoff that accompany uncontrolled development allow a stream to carry more sediment than it could...

Geochemistry of surface hyporheic stream sediments, multivariate statistics and GIS database proved successful tools for assessing toxic element contamination in East Attica region. The objectives of this study were to assess the degree of contamination and to describe the surface hyporheic stream sediment geochemical variations in relation to geology, lithology and anthropogenic activities of ...

We hypothesise that stream sediment elemental composition can predict mean and minimum concentrations of alkalinity, Ca and Mg in the river water throughout a river network. We tested this hypothesis for the River Derwent catchment in North Yorkshire, England, by using 6 years of water chemistry data from the Environment Agency and a digital elevation model to flow path-weight British Geologica...

Accumulations of sediment beneath the Antarctic Ice Sheet contain a range of physical and chemical proxies with the potential to document changes in ice sheet history and to identify and characterize life in subglacial settings. Retrieving subglacial sediments and sediment cores presents several unique challenges to existing technologies. This paper briefly reviews the history of sediment sampl...