Consulta: creatorFacets:"Bonin, P"
Registros recuperados: 3
Data/hora: 01/06/2024 08:03:45

Comparison of methods for measuring denitrifying activity in marine-sediments from the western mediterranean coast
Provedor de dados: 5
Autores: Raymond, N; Bonin, P; Bertrand, Jc.
Different types of denitrification rates in coastal marine sediments from the Western Mediterranean coast (France) were simultaneously determined by varioUS C2H2 inhibition techniques: in situ denitrifying activity in intact cores or sediment slurries; DEA (Denitrifying Enzyme Assays); and potential activity. Denitrifying activity was also estimated by the use of kinetic parameters (Km and V(max)). Values for denitrifying activities in the top two centimetres ranged from 0 to 50-mu-moles of nitrous oxide produced per litre of sediment per day, and were similar when intact core or sediment slurries were used. DEA showed comparable values for all the study sites. The potential activity ranged from 298-600-mu-moles per litre per day. Estimated activity based...
Tipo: Text
Palavras-chave: DENITRIFICATION; C2H2 BLOCKAGE; MARINE SEDIMENT; MEDITERRANEAN.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00100/21148/18767.pdf

Influence of shellfish farming activities on nitrification, nitrate reduction to ammonium and denitrification at the water-sediment interface of the Thau lagoon, France
Provedor de dados: 5
Autores: Gilbert, F; Souchu, Philippe; Bianchi, M; Bonin, P.
The seasonal patterns of nitrification, denitrification and dissimilatory ammonium production (DAP) rates were studied in the sediment of 2 stations in the Thau lagoon (south of France). The station ZA was located within the shellfish farming zone and the station B was the reference site. A marked effect of shellfish fanning on bacterial activities was observed. Spatial differences were associated with discrepancies in the organic content and the reduction state of sediments, i.e. highest reductive processes (denitrification and DAP) were noted in shellfish farming area, whereas the oxidative process (nitrification) was predominant outside the farming zone. At both stations, the DAP activity increased in September (autumn) concomitant with an increase of...
Tipo: Text
Palavras-chave: Shellfish farming; Nitrogen bacterial processes; Nitrification; Nitrate reduction to ammonium; Denitrification; Thau lagoon; Mediterranean Sea; Sediment-water exchanges.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00070/18145/15697.pdf

Reduction du nitrate dans les sediments marins. Comparaison des activites mesurees in vitro et in situ
Provedor de dados: 5
Autores: Esteves, J; Bonin, P; Blanc, F; Mille, G; Bertrand, J.
In vitro nitrate reduction in hydrocarbon-polluted marine sediments has been studied by flow-through system. By analysing the rate of nitrate comsumption as a function of nitrate concentration the authors determined the Michaelis-Menten kinetics parameters. (km = 330 mu M; vax = 2.0 mu M/g super(-1)/h super(-1). The authors found a value of 60 mu M/m super(-2)/h super(-1) for the rate of in vitro nitrate consumption derived from the above kinetic parameters and from the nitrate concentration in the sediment. In parallel a value of 67.4 mu M/m super(-2)/h super(-1) was found for the rate of nitrate consumption under in situ conditions. The great similarity between both results would favor the in vitro technique as a valid and more convenient one.
Tipo: Text
Palavras-chave: MED; Biogeochemistry; Oil pollution; Methodology; Environmental conditions; Experimental research; Comparative studies; Metabolism; Bacteria; Sediment chemistry; Reduction; Nitrates; Denitrification; Nitrogen cycle.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-979.pdf