The Influence of Heavy Metals on Growth and Development of Eichhornia crassipes Species, Cultivated in Contaminated Water

摘要

Many plants are capable of accumulating heavy metals (called hyperacumulators), one of which is the water hyacinth Eichhornia crassipes Mart. The roots of this water plant naturally absorb pollutants, including heavy metals such as Pb, Hg, Zn, Co, Cd, and Cu and can be used for wastewater treatment. The aim of this study was to assess the influence of heavy metals on growth and development of water hyacinth and to determinate the uptake capacity of heavy metals of this species. It was evaluated for its effectiveness in reducing pollution potential in wastewater. From the combination of experimental factors 11 variants resulted. The results showed that Eichhornia absorbed a high quantity of Pb (504 mg/kg dry matter) and Cu (561 mg/kg dry matter) in their roots. More Cu accumulated in the root compared to Pb. The level of Zn absorption was lower in roots (84 mg/kg dry matter) and also in stem plus leaves (51 mg/kg dry matter). A high quantity of Cd (281 mg/kg dry matter) was removed from stem plus leaves of Eichhornia while the level of Co was very low (45 mg/kg dry matter). Regarding the growth and development of this plant it was found that in tanks with Pb plants had a better development and had flowers also, and in the case of Cd, Co, Cu at a double dose of maximum admissible limits, the plants died and the growing period was shorter.