Biomonitoring with benthic macroalgae and direct assay of heavy metals in seawater of the Oporto coast (northwest Portugal)
Leal, M.C.F.; Vasconcelos, M.T.; Sousa-Pinto, I.; Cabral, J.P.S. (1997). Biomonitoring with benthic macroalgae and direct assay of heavy metals in seawater of the Oporto coast (northwest Portugal). Mar. Pollut. Bull. 34(12): 1006-1015 In: Marine Pollution Bulletin. Macmillan: London. ISSN 0025-326X; e-ISSN 1879-3363, more |   |
| Authors | | Top | - Leal, M.C.F.
- Vasconcelos, M.T.
- Sousa-Pinto, I., more
- Cabral, J.P.S.
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| Abstract | The concentrations of dissolved Cd, Cu, Hg and Pb in seawater and algae (Enteromorpha spp, andPorphyra spp,) were determined in parallel on three beaches located in the Oporto coast (Portugal), during 8 successive months, comprising periods of low and high biological productivity, The concentrations of dissolved metals in seawater varied markedly during the sampling period and exhibited seasonality. The concentrations of Cd were high in autumn and winter, but low in spring, The concentrations of Cu and Hg were high in autumn, low in winter and peaked in May, The concentrations of Pb were low in autumn and winter, and also peaked in May, It is likely that biological activity was, at least partially, responsible for the observed seasonal changes, The mean concentrations of dissolved metals in seawater were similar to those reported for polluted and industrialized european coastal areas, Metal concentration factors, calculated month-to-month for each alga, metal and site, varied markedly during the sampling period, indicating that concentration factors based on single or few determinations could be misleading, On the contrary, mean concentration factors (calculated by dividing the mean metal concentration in the algae by the mean metal concentration in seawater) were relatively constant at all three sites, indicating that in the Oporto coast, Enteromorpha spp, can be used to estimate the mean concentration of dissolved Cd, Cu and Hg in seawater, and Porphyra spp., the mean concentration of Cd, Cu and Pb, However, considering that future estimates of the concentrations of these metals in seawater should be based on determinations of the metal contents in Enteromorpha spp, and Porphyra spp, carried out on several occasions spanning a considerable period of time, the use of these algae as monitors of heavy metal pollution can have limited practical advantages over the direct assay of the metals in seawater. |
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