The Sediment Quality Triad (SQT) consists of complementary measures of sediment chemistry, benthic community structure, and sediment toxicity. We applied the SQT at 20 stations in the tidal portion of the Anacostia River from Bladensburg, MD to Washington, DC to establish a baseline of conditions to evaluate the effects of management actions. Sediment toxicity was assessed using 10-day survival...

Here we present a novel approach for the interpretation of stable isotope signatures recorded in benthic foraminifera from subtidal estuarine environments. The stable isotopic composition (δ18O and δ13C) of living Ammonia tepida and Haynesina germanica is examined at four stations in the Auray River estuary (Gulf of Morbihan, France) sampled in two contrasting seasons, spring 2006 and winter 20...

In shallow macrotidal ecosystems with large intertidal mudflats, the sediment-water coupling plays a crucial role in structuring the pelagic microbial food web functioning, since inorganic and organic matter and microbial components (viruses and microbes) of the microphytobenthic biofilm can be suspended toward the water column. Two experimental bioassays were conducted in March and July 2008 t...

Development of repeatable and quantitative tools are necessary for determining the abundance and distribution of different types of benthic habitats, detecting changes to these ecosystems, and determining their role in the global carbon cycle. Here we used ocean color remote sensing techniques to map different major groups of primary producers and estimate net primary productivity (NPP) across ...

Bivalve aquaculture introduces high densities of farmed organisms to the natural environment with potential consequences on a number of ecosystem processes, including modification of nutrient fluxes (e.g. NH4, NOX, PO4, and Si(OH)4) and benthic respiration, and may impact benthic communities. Infaunal clam culture may influence the environment due to the clams themselves [their metabolic proces...

Bioturbation activity of sediment-dwelling organisms promotes the release of contaminants across the benthic-pelagic ecosystem boundary, thereby affecting the exposure to and uptake of sediment associated contaminants at the sediment-water interface by themselves and the entire community around them. This way, bioturbation activity may contribute to species specific sensitivities to sediment as...

A methodology for reoxygenation of in situ benthic chamber systems by enzymatic catalysis of hydrogen peroxide with catalase was developed. For a 10-liter benthic chamber, the injection of 1 ml of catalase suspension (26,000 U ml) followed by 10 ml of 0.5 M hydrogen peroxide solution resulted in complete reoxygenation within 2.5 min at 25 degrees C.

Oxygen and carbon isotope ratios of benthic foraminifers were measured on the continuous middle to lower bathyal sedimentary sequence dated from the upper Maestrichtian to lower Eocene which was recovered at Site 752 in the eastern Indian Ocean. The changes in the carbon isotope values can be correlated with the faunal changes of the benthic foraminifers.

One of the most pervasive human impacts to salt marshes around the world is the introduction of nonnative species. Plant introductions to salt marsh systems have resulted in significant changes ranging from species replacement to broad-scale alteration of ecosystem properties. In this chapter, we examine the changes produced by the invasive Atlantic smooth cordgrass Spartina alterniflora in two...

We summarized studies on the impacts and scale effects of negative (competition, predation, parasitism, herbivory) and positive (mutualism, commensalism, indirect facilitation) species interactions in freshwater benthic habitats since ,1986 and focused on organisms with mainly or entirely aquatic life cycles. Benthologists publishing in J-NABS have contributed robustly to our overall knowledge ...