Consulta: creatorFacets:"Launeau, P."
Registros recuperados: 2
Data/hora: 13/06/2024 00:57:17

Two-dimensional distribution of living benthic foraminifera in anoxic sediment layers of an estuarine mudflat (Loire Estuary, France)
Provedor de dados: 5
Autores: De Chanvalon, A. Thibault; Metzger, E.; Mouret, A.; Cesbron, F.; Knoery, Joel; Rozuel, Emmanuelle; Launeau, P.; Nardelli, M. P.; Jorissen, F. J.; Geslin, E.
We present a new rapid and accurate protocol to simultaneously sample benthic living foraminifera in two dimensions in a centimeter scale vertical grid and dissolved iron in high resolution (200 μm). Such an approach appears crucial to study foraminiferal ecology in heterogeneous environments. The foraminiferal faunas of the main intertidal mudflat of the Loire estuary are dominated by Ammonia tepida, which accounts for 92 % of the living assemblage (CTG-labeled). Its vertical distribution shows a first density maximum at the surface, a sharp decrease in the next two centimeter followed by a well defined second maximum between 3 and 8 cm depth. The heterogeneity of A. tepida in this 3–8 cm depth layer was calculated by the Moran's Index and reveals lateral...
Tipo: Text
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00277/38786/37335.pdf

Simultaneous nitrite/nitrate imagery at millimeter scale through the water-sediment interface
Provedor de dados: 5
Autores: Metzger, E.; Thibault, Aubin; Cesbron, F.; Barbe, A.; Launeau, P.; Jezequel, D.; Mouret, A.
The present study describes new procedures to obtain at millimeter resolution the spatial distribution of nitrite and nitrate in porewaters, combining diffusive equilibrium in thin films (DET), colorimetry and hyperspectral imagery. Nitrite distribution can be easily achieved by adapting the well-known colorimetric method from Griess (1879) and using a common flatbed scanner with a limit of detection about 1.7 µmol L-1. Nitrate distribution can be obtained after reduction into nitrite by a vanadium chloride reagent. However, the concentration of vanadium chloride used in this protocol brings coloration with a wide spectral signature that creates interference only deconvolvable by imaging treatment from an entire visible spectrum for each pixel (spectral...
Tipo: Text
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00344/45510/45064.pdf