Titre de série :	United States Geological survey water supply paper, 2307
Titre :	Analysis and interpretation of water-quality trends in major U.S rivers, 1974-1981
Type de document :	texte imprimé
Auteurs :	Smith, A. R. ; Alexander, B. R. ; Gardon, W. M.
Mention d'édition :	USGPO
Editeur :	USGPO
Année de publication :	1987
ISBN/ISSN/EAN :	CI-04012
Note générale :	Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.
Langues :	Anglais (eng)
Mots-clés :	Qualité de l'eau  Analyse de l'eau  Hydrochimie  Réseau hydrographique  Hydraulique urbaine
Index. décimale :	627 Génie hydraulique
Résumé :	Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.
Note de contenu :	Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.

United States Geological survey water supply paper, 2307. Analysis and interpretation of water-quality trends in major U.S rivers, 1974-1981 [texte imprimé] / Smith, A. R. ; Alexander, B. R. ; Gardon, W. M.  . -  USGPO . - USGPO, 1987.
ISSN : CI-04012
Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.
Langues : Anglais (eng)

Mots-clés :	Qualité de l'eau  Analyse de l'eau  Hydrochimie  Réseau hydrographique  Hydraulique urbaine
Index. décimale :	627 Génie hydraulique
Résumé :	Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.
Note de contenu :	Water quality records from two nationwide sampling networks are now of sufficient length to permit nationally consist analysis of long-term water-quality trends at more than 300 locations on major US rivers. Particularly noteworthy are widespread decreases in lead and fecal bacteria concentrations and widespread increases in nitrate, arsenic, and cadmium concentrations. There is evident that atmospheric deposition of a variety of substances has played a surprisingly large role in water-quality changes.