Data/hora: 05/06/2024 17:12:02

Provedor de dados: | 5
País: | France
Título: | Comportement géochimique des herbicides et de leurs produits de dégradation en milieu estuarien et marin côtier
Autores: | Munschy, Catherine.
Data: | 1995-04-11
Ano: | 1995
Palavras-chave: | Estuaires; Herbicides; Chloro-triazines; Dé-éthylatrazine; Comportement géochimique; Phase dissoute; Conservativité; Flux; Estuaries; Herbicides; Chloro-triazines; De-ethylatrazine; Geochemical behaviour; Conservative mixing; Flux.
Resumo: | The presence and geochemical behaviour of herbicides were investigated in estuarine and marine waters of the French coasts (Seine, Charente, Gironde estuaries and Rhône delta). These organic contaminants were quantified by capillary Gas Chromatography (GC) using Nitrogen-Phosphorus Detecter and identified by GCIMS (Mass Spectrometry). A liquid-solid extraction method using XAD-2 resins was developed,  allowing the analysis of both chloro-triazines and their degradation products in the nanogram per litre (ng.l-1) detection range. Different types of chemicals were identified in the estuarine and coastal waters: triazine, amide and acetanilide herbicides. These compounds are mainly present in the water phase, with less than 1% associated with particulate matter. Simazine, atrazine and de-ethylatrazine (DEA), one of the degradation products of atrazine, were detected at ali sampling sites and during ali seasons. The concentration levels of herbicides depend on location, season and type of compounds. The concentrations of simazine, atrazine and DEA in the fluvial zone ranged between 21-299 ng.l-1, 35-591 ng.l-1 and 23-110 ng.l-1 respectively, and between 5-63 ng.l-1 , 4-70 ng.l-1 and 5-19 ng.l-1 in high salinity waters (S&gt;30). The dissolved herbicides behave conservatively during estuarine mixing. Gross riverine fluxes of pesticides transported by rivers into the estuaries are similar to net fluxes exported to the sea. Gross fluxes of dissolved atrazine vary between 0.12 kg.d-1 in the Charente estuary and 25.1 kg.d-1 in the Gironde estuary, and between 0.11 and 7.4 kg.d-1 for DEA in the Charente estuary and Rhône delta respectively.
Tipo: | Text
Idioma: | Francês

Identificador:

http://archimer.ifremer.fr/doc/00443/55443/56962.pdf

http://archimer.ifremer.fr/doc/00443/55443/

Editor: | Université Paris 6
Formato: | application/pdf

Fonte:

1995 Université Paris 6

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