Organic matter (OM) remineralization may be considered a key function of the benthic compartment of marine ecosystems and in this study we investigated if the input of labile organic carbon alters mineralization of indigenous sediment OM (OM priming). Using 13C-enriched diatoms as labile tracer carbon, we examined shallow-water sediments (surface and subsurface layers) containing organic carbon...

Sedimentary phosphorus sPd composition was investigated in Effingham Inlet, a fjord located on the west coast of Vancouver Island in Barkley Sound. Solid-state P nuclear magnetic resonance sNMRd spectroscopy was applied to demineralized sediment samples from sites overlain by oxic and anoxic bottom waters. The two sites were similar in terms of key diagenetic parameters, including the mass accu...

Unusual peaks in turbidity were detected in two branches of the Whittard Canyon in June 2013. Enhanced nepheloid layers (ENLs) were defined as layers with concentrations of suspended particulate matter exceeding those of nepheloid layers typically observed in a given region. Here, ENLs had peaks in turbidity and elevated suspended particulate matter concentrations exceeding ~1 mg L(-1) with the...

Although the deep sea is the largest ecosystem on Earth, its infaunal ecology remains poorly understood because of the logistical challenges. Here we report the morphology of relatively large burrows obtained by in situ burrow casting at a hydrocarbon-seep site and a non-seep site at water depths of 1173 and 1455 m, respectively. Deep and complex burrows are abundant at both sites, indicating t...

The aquatic eddy-correlation technique can be used to noninvasively determine the oxygen exchange across the sediment-water interface by analyzing the covariance of vertical flow velocity and oxygen concentration in a small measuring volume above the sea bed. The method requires fast sensors that can follow the rapid changes in flow and the oxygen transported by this flow to calculate the momen...

We present and compare small sediment-water fluxes of O2 determined with the eddy correlation technique, with in situ chambers, and from vertical sediment microprofiles at a 1450 m deep-ocean site in Sagami Bay, Japan. The average O2 uptake for the three approaches, respectively, was 1.62 ± 0.23 (SE, n = 7), 1.65 ± 0.33 (n = 2), and 1.43 ± 0.15 (n = 25) mmol m–2 d–1. The very good agreement bet...

We examined annual nutrient changes (nitrate, phosphate and ammonium) and the net dissolved organic carbon (DOC), nitrogen (DON) and phosphorus (DOP) release using in situ benthic incubations in a Posidonia oceanica meadow and in unvegetated sediments of Magalluf Bay (Mallorca Island, Spain) at monthly intervals. We also examined the role of the P. oceanica meadow in the C:N:P ratio transformat...

   This paper describes the work done between IUST and two Iranian steelworks to evaluate and review the performance of mould fluxes in current use for continuous casting. Calculations have been performed to compare actual values of powder consumption, viscosity and break temperature of the fluxes in current use with required values derived from published empirical rules for casting conditions....

Benthic foraminifera at Ocean Drilling Program (ODP) Hole 692B were studied to understand variations in oxygen and organic-matter fluxes bottom waters during the Early Cretaceous. The upper Berriasian lower Barremian black shales, characterized by high concentrations of total organic carbon (TOC) ranging between 1.3 18%, deposited an outer neritic-upper bathyal environment (~200–500 m) accordin...