YEAR COMPARISON OF CONTENTS OF THE RISK ELEMENTS IN STREAM-SIDE SEDIMENTS IN THE UPPER FLOW OF THE RIVER NITRA

摘要

The aim of the work was to compare the content of Cd, Pb, Ni, Zn, Cu, Cr, Co and Hg in Upper Nitra riverside in years 2011 and 2012. The samples of riverside sediments were collected from 9 sites along the upper flow of Nitra river. Distance between the starting site Opatovce upon Nitra and end point site Topo??any was about 50 km. Risk metals contents in the soil samples were determined and evaluated according Law 220/2004. The flame atomic absorption spectrometry was the used analytical method for heavy metal levels determination. The average values of pH/KCl were 7,32 (2011) and 7,19 (2012), it means 1,8 % decreased value in comparison to 2011. In 2012 the average Cd sediment content was by 6% higher and the Hg content up to three times higher than those in 2011. The improvement of present situation would be to take effective measures such as better cleaning of waste water from the industrial enterprises and urban agglomeration as well as new waste water treatment plants building.