La Tour du Valat

Institut de recherche pour la conservation des zones humides méditerranéennes

Titre :	Trace element speciation and behavior in the tidal Delaware River
Auteurs :	G. F. Riedel, Auteur ; J. G. Sanders, Auteur
Type de document :	Article
Dans :	Estuaries (21(1) MAR 1998)
Article en page(s) :	78-90
Résumé :	Measurements of dissolved As, Cr, Cu, and Se using species-selective techniques were made in the tidal freshwater Delaware River at four sites in July 1991, January 1992, and March 1992. Concentrations of dissolved As, Ct, and Sr were generally higher in July than in March or January. Copper concentrations were relatively constant. Both As and Cu increased in concentration in the region of Philadelphia. Measurements of As, Cd, Cr, Cu, Pb, Ni, Se, and Zn in seston were made during the July 1991 and March 1992 sampling using both a total digest and a series of sequential Leaches. A large fraction of most of the elements, in the order Cd > Zn > Ph Cu > Ni greater than or equal to As > Cr > Se, was solubilized by weak acid. The remainding fraction, for elements where the acid leach was not complete, was released by a rigorous digestion with concentrated acids. Based on estimates of similar rivers, Ph and Zn appear to he substantially enriched in Delaware River seston compared to other rivers draining, the same geological provinces. Arsenic, Se, and Cd in seston may be moderately enriched.

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