Mercury in sediments and pore waters at a contaminated site in the Tagus estuary

Mercury in sediments and pore waters at a contaminated site in the Tagus estuary

 Two sediment cores were collected at a contaminated site of the North Channel in the Tagus estuary. Sediments were sliced in 1 to 2-cm vertical sections. Major and minor elements, total organic carbon, total mercury (HNO3 digest), acid volatile sulphides –AVS– (1M HCl and 3M HCl) and simul...

Descrición completa

Gardado en:
Detalles Bibliográficos
Autores principales: Canário, J, Vale, C, Caetano, M
Formato: Online
Idioma:eng
Publicado: Iniversidad Autónoma de Baja California 2003
Acceso en liña:https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/163
Etiquetas: Engadir etiqueta
Sen Etiquetas, Sexa o primeiro en etiquetar este rexistro!
id oai:cienciasmarinas.com.mx:article-163
record_format ojs
spelling oai:cienciasmarinas.com.mx:article-1632019-04-25T00:16:25Z Mercury in sediments and pore waters at a contaminated site in the Tagus estuary Mercurio en sedimentos y aguas intersticiales de un sitio contaminado del estuario del Tajo Canário, J Vale, C Caetano, M mercury sediment pore waters Tagus estuary mercurio sedimento agua intersticial estuario del Tajo  Two sediment cores were collected at a contaminated site of the North Channel in the Tagus estuary. Sediments were sliced in 1 to 2-cm vertical sections. Major and minor elements, total organic carbon, total mercury (HNO3 digest), acid volatile sulphides –AVS– (1M HCl and 3M HCl) and simultaneously extractable iron, manganese and mercury were determined in the solids. Labile and total mercury (after UV irradiation) were measured in pore waters. Total mercury concentrations in the first 25 cm of sediment were around 100 nmol g–1, reflecting mainly anthropogenic discharges. A slightly compacted sediment layer (< 1 cm thickness) containing lower Hg concentrations (5 nmol g–1) capped the contaminated sediment. Mercury extracted with 1M HCl was only detected in this layer where AVS are low. In the sediment column, AVS were higher (50 to 197 µmol g–1), labile mercury was detected in pore waters down to 3.5-cm depth, and total dissolved Hg showed a broad maximum at 6 cm of depth (1.1 nM). The co-existence of high AVS and high total dissolved mercury implies the presence of ligands in pore waters with high affinity to mercury, which competes with sulphides and retains the metal in solution. Se colectaron dos núcleos de sedimento en un sitio contaminado del Canal del Norte del estuario del Tajo. Los sedimentos fueron cortados en secciones verticales de 1 a 2 cm. Se determinaron elementos mayores y menores, carbón orgánico, mercurio total (digeridos con HNO3), sulfuros volátiles en ácido –AVS– (HCl 1M y HCl 3M), así como hierro extraíble, manganeso y mercurio en los sólidos. El mercurio lábil y total (después de irradiarlo con UV) fue medido en aguas intersticiales. Las concentraciones totales de mercurio en los primeros 25 cm de profundidad del sedimento fueron de alrededor 100 nmol g–1, reflejando principalmente descargas antropogénicas. Una capa poco compactada de sedimento (< 1 cm de grosor) con bajas concentraciones de Hg (5 nmol g–1) cubría el sedimento contaminado. El mercurio extraído con HCl 1M sólo fue detectado en esta capa donde los AVS son bajos. En la columna de sedimento, los AVS fueron más elevados (50 a 197 µmol g–1). El mercurio lábil fue detectado en el agua intersticial hasta los 3.5 cm de profundidad y el Hg disuelto total mostró un amplio máximo a los 6 cm (1.1 nM). La coexistencia de una gran cantidad de AVS y un alto contenido de mercurio disuelto total implica la presencia de ligandos en las aguas intersticiales, con una alta afinidad al mercurio, los cuales compiten con los sulfuros y mantienen el metal en solución. Iniversidad Autónoma de Baja California 2003-03-06 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article Artículo Arbitrado application/pdf https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/163 10.7773/cm.v29i4.163 Ciencias Marinas; Vol. 29 No. 4 (2003); 535-545 Ciencias Marinas; Vol. 29 Núm. 4 (2003); 535-545 2395-9053 0185-3880 eng https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/163/139
institution Ciencias Marinas
collection OJS
language eng
format Online
author Canário, J
Vale, C
Caetano, M
spellingShingle Canário, J
Vale, C
Caetano, M
Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
author_facet Canário, J
Vale, C
Caetano, M
author_sort Canário, J
title Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
title_short Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
title_full Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
title_fullStr Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
title_full_unstemmed Mercury in sediments and pore waters at a contaminated site in the Tagus estuary
title_sort mercury in sediments and pore waters at a contaminated site in the tagus estuary
description  Two sediment cores were collected at a contaminated site of the North Channel in the Tagus estuary. Sediments were sliced in 1 to 2-cm vertical sections. Major and minor elements, total organic carbon, total mercury (HNO3 digest), acid volatile sulphides –AVS– (1M HCl and 3M HCl) and simultaneously extractable iron, manganese and mercury were determined in the solids. Labile and total mercury (after UV irradiation) were measured in pore waters. Total mercury concentrations in the first 25 cm of sediment were around 100 nmol g–1, reflecting mainly anthropogenic discharges. A slightly compacted sediment layer (< 1 cm thickness) containing lower Hg concentrations (5 nmol g–1) capped the contaminated sediment. Mercury extracted with 1M HCl was only detected in this layer where AVS are low. In the sediment column, AVS were higher (50 to 197 µmol g–1), labile mercury was detected in pore waters down to 3.5-cm depth, and total dissolved Hg showed a broad maximum at 6 cm of depth (1.1 nM). The co-existence of high AVS and high total dissolved mercury implies the presence of ligands in pore waters with high affinity to mercury, which competes with sulphides and retains the metal in solution.
publisher Iniversidad Autónoma de Baja California
publishDate 2003
url https://www.cienciasmarinas.com.mx/index.php/cmarinas/article/view/163
_version_ 1715723937727381504

Títulos similares