STUDY OF HEAVY METALS ACCUMULATION INDEX IN PLANTS USED IN POLLUTED SOILS PHYTOREMEDIATION PROCESS

The mine tailings have a high content in heavy metals, especially Zn, Cu, Mn, Pb, Ni, Cr and others. In phytoremediation activities of mine tailings dumps were used plant species with high capacity to adapt to the physical-chemical properties of this inorganic waste. During the vegetation period, on any soil type, the cultivated plant species extract and accumulate high amounts of heavy metals in roots and terrestrial parts. Metal translocation rate from soil and accumulation in tissues is dependent to metal species biodisponibility capacity from soil organic-mineral structures in correlation with a series of factors like: pH, ionic change capacity, temperature, water retention a.o. Through this experiment was studied the metals amount of accumulation in plants, in roots and also in terrestrial parts. So, in case of Medicago sativa and Festuca arundinaceea, using the Zn, Cu and Mn uptake coefficient was analyzed the rate of translocation in order to monitor the accumulations dynamic. It turned out that Medicago sativa plants registered a higher uptake coefficient value on Cu and Mn. Festuca arundinaceea plants have a higher rate of accumulation in case of Zn. Also, in case of mine tailings polluted soils, the Zn, Cu and Mn translocation degree is higher and in case of soils polluted with mine tailings and with biosolids addition is lower.