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| Deborde, Jonathan; Abrill, Gwenael; Mouret, Aurelia; Jezequel, Didier; Thouzeau, Gerard; Clavier, Jacques; Bachelet, Guy; Anschutz, Pierre. |
| A study was conducted in Arcachon Bay, France, to determine the effect of seasonal dynamics in a Zostera noltii meadow on P and Fe cycles in the superficial sediments of a tidal mudflat. The redox-sensitive Fe particulate pool and associated P in the root zone showed a seasonal variation following the growth and decay of Z. noltii biomass, with a maximum content during the growth period. In comparison, the bare sediments did not show significant seasonal changes. A dissolved inorganic phosphorus (DIP) uptake was measured from the water column to the sediment in vegetated sediments, whereas a net DIP efflux was observed in the unvegetated sediments. During the growth period, the formation of an iron oxihydroxide-rich zone occurred and acted as a trap for... |
| Tipo: Text |
Palavras-chave: Nutrient; Eelgrass growth; Intertidal zone; Lagoon; Early diagenesis. |
| Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00603/71539/69966.pdf |
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| Anschutz, Pierre; Deborde, Jonathan. |
| The speciation of Phosphorus (P) in geologic materials can inform diverse investigations in such as aquatic biogeochemistry, soil sciences, and paleo-oceanography. Here, we describe in detail a set of sequential extraction schemes to measure P concentrations from several operationally defined phases: pore water, exchangeable or loosely sorbed P, Fe-bound P, P associated with biogenic apatite, P associated with authigenic apatite and carbonate forms, P associated with detrital apatite and inorganic forms, and organic P. The two benefits of the procedures we describe compared to prior methodological studies are: (1) fast, simple and inexpensive colorimetric methods have been developed for P determination in all the different matrices; and (2) the Fe-bound... |
| Tipo: Text |
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| Ano: 2016 |
URL: https://archimer.ifremer.fr/doc/00375/48616/49431.pdf |
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| Deborde, Jonathan; Anschutz, Pierre; Chaillou, Gwenaelle; Etcheber, Henri; Commarieu, Marc-vincent; Lecroart, Pascal; Abril, Gwenael. |
| Suspended particles and surface waters were collected in the Gironde estuary (southwestern France) along the salinity gradient. Dissolved inorganic phosphorus (DIP) was analyzed in the filtered surface waters. The suspended particles were sequentially leached to determine five fractions of phosphorus: exchangeable or loosely sorbed P, reactive Fe-bound P, refractory Fe oxide-bound P, P associated with apatite and carbonates, and organic P. Experiments were conducted to determine the effects of temperature, salinity, and DIP concentration on phosphorus sorption/desorption processes. The concentration and distribution of particulate phosphorus was homogeneous along the salinity gradient of the estuary, whereas it was variable in time and space in the... |
| Tipo: Text |
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| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00603/71538/69943.pdf |
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| Mulder, Thierry; Cirac, Pierre; Gaudin, Mathieu; Bourillet, Jean-francois; Trainer, J.; Normand, Alain; Weber, O.; Griboulard, R.; Jouanneau, Jean-marie; Anschutz, Pierre; Jorissen, Frans. |
| Submarine canyons are narrow but deep submarine valleys that extend for hundreds of meters. They represent the most impressive structures that shape the present morphology of passive continental margins. They can occur off the mouth of rivers: the Tagus, Zaire, Amazon, and Orinoco in the Atlantic; the Indus in the Indian Ocean; and the Var, Rhone, and Ebro in the Mediterranean. Some are at times disconnected from any stream mouth such as the Nazare canyon, off Portugal, despite the fact that it is close to the coast. Some were connected to a river mouth during lowstands of sea level, such as the Wilmington canyon in the northwest Atlantic, or the Blackmud canyon in the northeast Atlantic. |
| Tipo: Text |
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| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/00071/18201/15769.pdf |
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