Phytoremédiation par Cyperus esculentus de sols pollués par les Eléments Traces Métalliques

Résumé

Today, pollution problems have become very crucial. Anthropogenic activities such as wastewater discharges, household waste, road traffic, the use of fertilizers and pesticides, industrial activities are considered as the main sources of pollution carrying high concentrations of Traces Metallic (ETM). These pollute the ecosystem and cause health problems. In order to contribute to the implementation of biological techniques to remedy this pollution and restore soil quality, the phytoremediation by Cyperus esculentus of two soils polluted by the ETM was considered. After one month of culture Cyperus esculentus showed a good development similar to that of the control grown in unpolluted soil. The lengths of the whole plant of Cyperus esculentus were 65 cm in the control soil versus 63 cm in the polluted soil. The lengths of the aerial and underground part of Cyperus esculentus were 49 cm and 16 cm in the control soil and 48 and 15 cm in the polluted soil. These results thus show that Cyperus esculentus has a good tolerance to the toxicity of the MTEs present in the polluted soil. Phytoremediation of ETM by Cyperus esculentus showed that in low polluted soil Cyperus esculentus reduced by 110.96%, 0.025% and 51.26% respectively an initial Zn concentration of 66.8 mg / kg, Pb of 61.31 mg / kg and Cu 33.61%. In highly polluted soil Cyperus esculentus reduced by 10.63%, 120%, 34.67% and 44.27% respectively an initial Pb concentration of 125 mg / kg, Cd of 0.58 mg / kg, Cu of 208.48 mg / kg and Zn 139.83 mg / kg. These results indicate that Cyperus esculentus is a good candidate for the phytoremediation of Pb, Cd, Cu and Zn.