Relationship of Estuarine Plant Contaminants to Existing Data Bases
Abstract
A field survey was conducted to assess the pollution levels in plants, sediments and waters of the Sado river basin (in the south of Portugal), an area thought to be contaminated with mine effluents and industrial discharges. Field sampling was carried out in the Sado estuary, where sediments and Halimione portulacoides (a salt marsh species) were collected. In the upper zone of the Sado basin, near the pyrites mines of Aljustrel and Lousal, holm-oak (Quercus rotundifolia) and rush (Juncus conglomeratus) plant materials were collected, as well as soil and water samples. Although Sado estuary sediments presented relatively high levels of Cu, the plant did not reveal signs of metal accumulation - their Cu contents were similar to those found on control plants from uncontaminated salt marshes of the Mira river estuary, and to those reported in the literature for uncontaminated plants. Holm-oak trees growing near the pyrites mines presented high heavy metal contents in the leaves and acorns. Metal accumulation in acorns poses a serious health hazard, because these fruits are consumed by local population. Pb levels in acorns are particulary worrying. Juncus conglomeratus growing on an effluent ditch at Lousal mines revealed remarkable adaptation to heavy metal stress. Apparently, the plant was capable of tolerating the extremely high metal concentrations in the sediment, through prevention of translocation from the roots to the shoot.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1988
- Accession Number
- ADA201725
Entities
People
- Fernando S. Henriques
- J. C. Fernandes
Organizations
- NOVA University Lisbon