IADO   05364
INSTITUTO ARGENTINO DE OCEANOGRAFIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
DISSOLVED AND PARTICULATE METALS DISTRIBUTION, AND THEIR
Autor/es:
BELTRAME M. ORNELA, DE MARCO SILVIA, MARCOVECCHIO JORGE
Lugar:
Bahia Blanca, Argentina
Reunión:
Congreso; ECSA 44; 2008
Institución organizadora:
IADO- CONICET, ECSA
Resumen:
Trace metals have proven to be significantly hazardous pollutants in aquatic
environments, even at very low concentrations. Mar Chiquita Coastal Lagoon covers an
area of approximately 60 km2, and drains a tributary watershed of 10000 km2, where a
very important agricultural land use is developed. Besides, agriculture has been
identified as a source of heavy metals via fertilizers and pesticides. Although chemical
and biological processes are common to most estuaries, the distributions of trace metals
greatly vary among them, depending on environmental factors such as hydrodynamics,
residence times, mixing patterns and transport processes. The present work deals with
the analysis of dissolved and particulate heavy metals (Cd, Pb, Cu, Zn, Ni, Mn, Cr) of
high environmental significance, and focusses on the relationships between both forms
and with the suspended particulate matter (SPM). Significant inter-relationships
between the concentrations of several metals, indicated similar sources and/or similar
geochemical processes controlling their levels. Unlike results obtained in other
estuaries, no relationships among metals with SPM were observed. The partition
coefficient of all metals was very variable. The annual average of hydrographic
parameters presented no evidence of abnormality in their distributions. This could
support the fact that no gross change in the chemical speciation of trace metals
occurred. A comparison with other estuaries and coastal areas indicated a great input of
heavy metals. These results suggest that Therefore, the human activities -specially
intense agriculture- within the drainage basin of Mar Chiquita Coastal Lagoon, may
cause metal pollution.2, and drains a tributary watershed of 10000 km2, where a
very important agricultural land use is developed. Besides, agriculture has been
identified as a source of heavy metals via fertilizers and pesticides. Although chemical
and biological processes are common to most estuaries, the distributions of trace metals
greatly vary among them, depending on environmental factors such as hydrodynamics,
residence times, mixing patterns and transport processes. The present work deals with
the analysis of dissolved and particulate heavy metals (Cd, Pb, Cu, Zn, Ni, Mn, Cr) of
high environmental significance, and focusses on the relationships between both forms
and with the suspended particulate matter (SPM). Significant inter-relationships
between the concentrations of several metals, indicated similar sources and/or similar
geochemical processes controlling their levels. Unlike results obtained in other
estuaries, no relationships among metals with SPM were observed. The partition
coefficient of all metals was very variable. The annual average of hydrographic
parameters presented no evidence of abnormality in their distributions. This could
support the fact that no gross change in the chemical speciation of trace metals
occurred. A comparison with other estuaries and coastal areas indicated a great input of
heavy metals. These results suggest that Therefore, the human activities -specially
intense agriculture- within the drainage basin of Mar Chiquita Coastal Lagoon, may
cause metal pollution.