| In the scope of the study of the "on-bottom/off-bottom" mortality model in the south of the Marennes Oléron Bay, the result of the 2003 multidisciplinary study (Dynamor) appears to be the hypothesis of an acute stress, "ultimate" trigger of the mortality episodes in June. In 2004 we aim to look for the nature of this stress through the physico-chemical analysis of the sediment (Eh, pH, sulphides and ammoniacal nitrogen), the organic matter and chlorophyll load on the surface of the sediment between April and July. Herbicides are also measured in the water column, south of the bay (Seudre), during the same period. A "precocious" (around the first week of June) and "weak" (lower mortality rate on this working site since 1997) mortality peak happens when the... |
