Will the power plant at Rio Manso, Brazil, cause elevated mercury levels of fish and reduced fish populations?
2003 (English)In: Revista Saúde e Ambiente, Vol. 6, no 1-2, 12-26 p.Article in journal (Refereed) Published
In newly constructed hydroelectric reservoirs, it has been shown that the mercury concentration in fish rises. This phenomenon is known mainly from studies in the Nothern Hemisphere. In the present study, the background levels of mercury in fish, soil, and sediment in an area of western Brazil were determined before the area was inundated due to the construction of a hydroelectric power plant. Predatory fish from Rio Manso and Rio Casca were analysed for mercury (Hg). The total Hg concentration in the 13 samples ranged between 72 and 755 ng/g w.w. Organic carbon, nitrogen, and sulphur, total Hg, and citrate-dithionite-bicarbonate (cdb) extractable aluminium, iron, and manganese of soil and sediment were also determined to get a better understanding of parameters influencing Hg geochemistry. The average Hg concentrations in soil and sediment were 24.5 and 24.7 ng/g dry weight, respectively, which is within the background levels found in the region. Both sediment and soil were rich in amorphous aluminium and iron oxy-hydroxides. Mercury correlated positively to these in sediments and negatively in soil. A strong positive correlation between mercury and sulphur was found in sediment. Finally, it is discussed how the hydro power plant has influenced the environment and especially the fish population, indicating an acute need of measures to minimize present and future deterioration.
Place, publisher, year, edition, pages
2003. Vol. 6, no 1-2, 12-26 p.
hidroelectric power plant, mercury in fish, mercury in soil
IdentifiersURN: urn:nbn:se:uu:diva-76455OAI: oai:DiVA.org:uu-76455DiVA: diva2:104367