Interpretación de tendencias históricas de contaminación por metales pesados en testigos de sedimentos de la ría de Pontevedra
- Rubio, B.
- Gago, L.
- Vilas, F:
- Nombela, M.
- García-Gil, S.
- Alejo, I.
- Pazos, O.
ISSN: 0212-5919
Ano de publicación: 1996
Volume: 12
Número: 1
Páxinas: 137-152
Tipo: Artigo
Outras publicacións en: Thalassas: An international journal of marine sciences
Resumo
It is often claimed that coastal areas and estuaries can preserve temporal records of anthropogenic input of heavy metals to the environment. Because of their large adsorption capabilities, finegrained sediments represent a major repository for contaminants. Thus, they can be used for historical reconstruction. Several reearches have used sediment cores to reconstruct the history of coastal pollution. The aim of this paper is the interpretation of vertical profiles of heavy metals in recent sediments from the Ría de Pontevedra. Four sediment cores were collected, in different muddy subaqueous area of the Ría, by using a gravity-corer. Corers lengths ranged betwwen 30 and 62 cm and were resampled in 2 cm intervals for analytical work. Total contents of Al, Fe, Nm, Ni, Co, Cr, Cu, Zn and Pb were determined by ICP-AES. The results have allowed us to differentiate two groups of elements showing a consistently different vertical distribution pattern: 1) Co, Ni and Cr contents showed nearly constatn values in all the corers and 2) Zn, Pb and Cu contents showed an upward increase. Aluminium was used as a normalizing factor to compensate for intersample variations in sediment texture. Principal component analysis applied to the element/Al ratio was used in order to obtain a global view of the differences.