5 - L'oxygène

A Control for Microbiological Functioning

by Gilles Billen (editorial coordination), Michel Poulin (editorial coordination)
december 2004
210 x 297 30 pages In stock
5,40 €
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Over nearly fifty kilometres downstream from Rouen, the Seine is oxygen-depleted for over six months of the year. This serious problem of water quality was even more acute in the sixties. The water's oxygenation level closely reflects the balance of algal photosynthesis, heterotrophic degradation of organic matter, produced by algae or brought by effluents, and of ammonium's oxydation into nitrates by nitrification. Oxygen inputs from the upstream flow and exchanges with the atmosphere are not sufficient to compensate for the deficit, once the flow rate falls below 500 m³/s. Mathematical modelling provides better understanding of short-term variations in the estuary's oxygenation, linked to tidal and seasonal cycles, and its long-term variations, linked to changes in human acivities in the basin over the past fifty years. This tool can assess the measure to be taken to improve the oxygen level in future.

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Language(s): French

Publisher: Ifremer

Edition: 1st edition

Collection: Programme scientifique Seine-Aval

Published: 1 december 2004

Reference Booklet: SA9908

EAN13 Booklet: 9782844330307

Format (in mm) Booklet: 210 x 297

Pages count Booklet: 30

Weight (in grammes): 153


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