Fitorremediação por meio de plantas ornamentais para recuperação de áreas urbanas contaminadas com chumbo

Abstract

This study aimed to evaluate the resistance of ornamental plants in environments contaminated with Pb (lead) and determine whether they can be used for lead remediation in the environment. The study of the potential to absorb / adsorb lead form the contaminated soils of Tradescantia pallida (purple-heart), Ophiopogon jaburan (mondo grass), Sansevieria trifasciata (mother-in-law's tongue) and Cuphea gracilis (false-heather). The plants were placed into plastic pots containing soil and substrate. The experiment was distributed in a completely randomized design and added to the soil the amount of approximately 20.0 grams of lead sulfate II (PbSO4), there was also the witness for reference purposes, with four replications, totaling thirty-two vessels. During the experiment the plants were weekly photographic for monitoring and comparing the development of plants. After 20 weeks of contamination the plants were prepared for laboratory chemical analysis made by atomic absorption spectroscopy and flame plasma. The results showed that all species have the potential to adsorb Pb into the roots. To visually evaluate the growth of the species comparing the uncontaminated and contaminated individuals, could not be verified evidence of intoxication, and these had a normal growth. With the exception of S. trifasciata, the plants develop defense mechanisms to prevent the contaminant is translocated to the shoot. All species receiving contamination Pb showed an appearance similar to that of control plants and none of the individuals died, indicating a resistance for element.