Resumo:
Contamination by oil spills in coastal ecosystems, especially in mangrove zones, has been common in countries with oil industry. The aim of this study was, therefore, to evaluate the efficiency of application of the two models developed for pilot-scale
remediation, intrinsic bioremediation (indigenous microorganisms), and phytoremediation (Avicennia schaueriana). The degradation of hydrocarbons was determined by gas chromatography (GS) with flame ionization detector. The metals Al, Fe, Pb, Cr, Cu, Zn,and Ni were determined by flame atomic absorption spectrometry in the mangrove
simulated with sediment of Todos os Santos Bay, Brazil. These models also monitor
other biogeochemical parameters (nitrogen, phosphorus, total organic carbon, pH,
redox potentioal, dissolved oxygen, salinity, temperature, bacterial density). The integrated assessment of data showed that both techniques were effective in degrading
organic compounds from oil but that phytoremediation is the most efficient (89% removal). The intrinsic ioremediation model has no direct correlation with metal concentrations, but a positive correlation with Al and Ni was found in the ydrocarbon
removal by phytoremediation. Avicennia schaueriana represents efficiency in phytoextraction and phytostimulation. The results suggest that the phytoremediation
model, through its various mechanisms, may become a technique for the removal of
petroleum hydrocarbons in the presence of metals in mangrove ecosystems near
industrial areas.
