Plant contamination by heavy metals in the impact zone of Novocherkassk Power Station in the south of Russia

The aim of this study is the assessment of Ni, Mn, Cd, Cu, Pb, Cr and Zn accumulation by different herbaceous species and soils on the technogenic areas around power station from the results of long-term monitoring observations. Soil and plant samples were taken annually in the second decade of June from monitoring plots on the areas around Novocherkassk Power Station (Rostov region, South of Russia). Vegetative part of such plants as Ambrosia artemisiifolia L., Achillea nobilis L., Artemisia austriaca, Tanacetum vulgare L., Elytrigia repens L. and Cichorium intybus L. was under the study. The total concentrations of Cr, Ni, Mn, Cd, Cu, Zn and Pb in the soils were determined by X-ray fluorescent scanning spectrometer. Heavy metals in plants were prepared for analysis by dry combustion at 450 A degrees C. The heavy metal concentration in extracts from plants was determined by FAAS. The effect of emissions from the power station on the metal concentration in herbaceous plants and soils was established. Contamination of herbaceous plants and soils with Zn, Cd and Pb on the monitoring plots located at 5 km to the northwest from the power station and the adjacent plots to the emission source was revealed. The metal concentrations in plants growing on sandy alluvial-meadow soil were higher than in the neighbouring light clayey meadow-chernozemic soil by 1.2-2.7 times. It was revealed that T. vulgare, Ambrosia artemisiifolia and C. intybus accumulate a higher concentration of heavy metals (HMs) in their aboveground parts than in roots under technogenic pollution. The results of the 13-year-long monitoring studies showed the increasing of all studied HM concentrations in the wild plants growing within 5 km from the Novocherkassk Power Station (NPS) along the predominant wind direction. The accumulation features of elements on the monitoring plots indicate that the NPS is the main source of aerotechogenic contamination of herbaceous plants and soils with the studied HMs on this area.