Skip to Main content Skip to Navigation
Theses

Modalités de contamination par les polluants organiques persistants des réseaux trophiques lagunaires. Application de la méthode des isotopes stables

Ana Persic
Abstract : As a part of a national biomonitoring project, the principal objective of this study was the determination of bioaccumulation patterns of persistent organic pollutants POPs : organochlorinated pesticides and polychlorobiphenyls within aquatic food webs in the Camargue Biosphere Reserve. The stable carbon and nitrogen isotope analysis, performed on 16 dominant aquatic animal species, confirmed the high complexity of trophic relations, but also their stability determined by constraints related to the natural and anthropic environmental fluctuations. After the detection of all the investigated POPs in all trophic levels, the possible bioaccumulation patterns of the contaminants were analysed. By using the isotopic method, biomagnification process was highlighted for the most persistent pollutants (dieldrin, HCB) but also for Αendosulfan, whose trophic transfer depends on the intensity of the contamination resulting from the biodisponibility of the substance, itself related to the season. For all the other analyzed substances, the bioconcentration directly from water seems to be the dominant way of contamination in a shallow aquatic ecosystem such as the Vaccarès lagoon. Additionally, some biomarkers were validated in situ in relation to the trophic level and the food web structure. The evaluated biochemical indicators failed to demonstrate the existence of a hypothetical "universal biomarker". A synthetic biological parameter of metabolic capacities would represent a considerable asset for such validation. The influence of a chemical or physical disturbance on metabolic allocation of 13C and 15N, supposed stable under given conditions, could be a promising approach.
Complete list of metadatas

https://tel.archives-ouvertes.fr/tel-00008851
Contributor : Ana Persic <>
Submitted on : Wednesday, March 23, 2005 - 12:47:22 PM
Last modification on : Wednesday, March 23, 2005 - 12:47:22 PM
Long-term archiving on: : Friday, September 14, 2012 - 12:15:25 PM

Identifiers

  • HAL Id : tel-00008851, version 1

Collections

Citation

Ana Persic. Modalités de contamination par les polluants organiques persistants des réseaux trophiques lagunaires. Application de la méthode des isotopes stables. Interactions entre organismes. Université Paris Sud - Paris XI, 2004. Français. ⟨tel-00008851⟩

Share

Metrics

Record views

827

Files downloads

5931