Citation: Berthelot H, Bonnet S, Camps M, Grosso O and Moutin T (2015) Assessment of the dinitrogen released as ammonium and dissolved organic nitrogen by unicellular and filamentous marine diazotrophic cyanobacteria grown in culture. Front. Mar. Sci. 2:80. doi: 10.3389/fmars.2015.00080 Assessment of the dinitrogen released as ammonium and dissolved organic nitrogen by unicellular and filamento...

Dissolved inorganic and organic nitrogen levels are elevated in aquatic systems due to anthropogenic activities. Dissolved organic nitrogen (DON) arises from various sources, and its impact could be more clearly constrained if specific sources were identified and if the molecular-level composition of DON were better understood. In this work, the pharmaceutical carbamazepine was used to identify...

Coastal ecologists and managers have frequently used nitrogen stable isotopes (delta15N) to trace and monitor sources of anthropogenic nitrogen (N) in coastal ecosystems. However, the interpretation of delta15N data can often be challenging, as the isotope values fractionate substantially due to preferential retention and uptake by biota. There is a growing body of evidence that carbon isotopes...

Riverine nitrogen distribution is increasingly controlled by anthropogenic activities in their watersheds, regardless of spatial scale, climate, and geographical zone. Consequently, modelling efforts to predict the export of nitrogen from rivers worldwide have used attributes such as population density, land use, urbanization and sanitation. These models have greatly enhanced our understanding ...

Quantitative studies of the dissolved nitrogen in man have been previously made only for short periods of time, chiefly in determinations of cardiac output (Bornstein, 1919). Measurements of nitrogen absorption and elimination not only give an approximation of cardiac output, but also a’fford a representation of the absorption and elimination of all chemically inert gases, specifically the inha...

Access to bioavailable nitrogen often limits primary production in marine and freshwater ecosystems. Around 70% of nitrogen transported by rivers worldwide consists of dissolved organic nitrogen (DON), but its bioavailability has been poorly investigated. To assess the potential bacterial growth on DON, we developed a bioassay employing natural DON and bacterial inocula in medium manipulated to...

All steels contain some amount of dissolved gases such as oxygen, hydrogen and nitrogen of which nitrogen is effective in improving the mechanical and corrosion properties of stainless steels if it remains in solid solution or precipitates as very fine and coherent nitrides or carbo-nitrides with iron or alloying elements. When nitrogen is added to austenitic steels it can simultaneously improv...

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of...

A model of the concentrations of suspended solids (SS) in the aeration tanks and in the effluent from these during Aeration tank settling (ATS) operation is established. The model is based on simple SS mass balances, a model of the sludge settling and a simple model of how the SS concentration in the effluent from the aeration tanks depends on the actual concentrations in the tanks and the slud...