Nitrogen patterns in subsurface waters of the Yzeron stream: effect of combined sewer overflows and subsurface-surface water mixing.
Water Sci Technol
; 68(12): 2632-7, 2013.
Article
em En
| MEDLINE
| ID: mdl-24355851
ABSTRACT
Urbanization subjects streams to increased nitrogen loads. Therefore studying nitrogen forms at the interface between urban stream and groundwater is important for water resource management. In this study we report results on water δ(18)O and nitrogen forms in subsurface waters of a stream (Yzeron, France). The sites studied were located upstream and downstream of combined sewer overflows (CSO) in a rural area and a periurban area, respectively. Water δ(18)O allowed us to follow the mixing of subsurface water with surface water. Dissolved organic nitrogen and organic carbon of fine sediment increased by 20-30% between rural and periurban subsurface waters in the cold season, under high flow. The highest nitrate levels were observed in rural subsurface waters in the cold season. The lowest nitrate levels were found in periurban subsurface waters in the warm season, under low flow. They corresponded to slow exchange of subsurface waters with channel water. Thus reduced exchange between surface and subsurface waters and organic-matter-rich input seemed to favor nitrate reduction in the downstream, periurban, subsurface waters impacted by CSO.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Esgotos
/
Água Subterrânea
/
Monitoramento Ambiental
/
Hidrodinâmica
/
Água Doce
/
Nitrogênio
País como assunto:
Europa
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article