CHROMIUM BIOACCUMULATION IN SOME HERBACEOUS SPECIES FROM CONSTANTA LITTORAL AREA (ROMANIA)

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-12-6 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 61, 1183-1190 pp, DOI: 10.5593/sgem2017/61/S25.154

ABSTRACT

Screening the local flora for metal bioaccumulators is of great importance, the aim being that of finding species valuable for bioremediation (bioindicators, phytostabilizers, phytoextractors) or biomining.

Chromium content was determined, through atomic absorption spectrometry (HR-CSAAS, air-acetylene, 357 nm) in aboveground organs eight common species growing on the beaches and adjacent areas in Constanta, Romania: Argusia sibirica, Atriplex sagittata, Echium italicum, Conium maculatum, Malva sylvestris, Onopordum acanthium, Plantago lanceolata and Rumex crispus. Corresponding soil samples for Cr content were also analyzed and Biological Accumulation Coefficients (BAC) was determined.

In all analyzed species, Cr content was above the “standard reference” value of 1.5 mg/kg. The highest concentrations were found in O. acanthium (32.75 mg/kg average), however, these are far below the 1,000/300 mg/kg minimal conventional threshold for Cr hyperaccumulation. Other species with high Cr content were M. sylvestris, E. italicum and C. maculatum.

None of the eight species had a BAC above 1, while average values higher than 0.5 were found in O. acanthium, M. sylvestris and E. italicum.

Results show that, while having an above-average Cr content, none of the selected species is valuable as a phytoextractor, under natural conditions. However, high metal concentration, as well as BAC values indicate a possible potential for phytostabilization in O. acanthium, M. sylvestris and E. italicum, requiring further research to be confirmed.

Keywords: phytoaccumulation, chromium, herbs, biological accumulation coefficient, coastal area