The work shows the determination of selected metals (Zn, Pb, Cd...) in various plant samples and sediment. To determine the concentrations I used the method and the device with inductively coupled plasma with optical emission spectroscopy. Before the determination, I prepared all samples with acidic microwave digestion. The plants sampled on the island of Maribor were Japanese knotweed and winter horsetail. There is a power plant near the island of Mariborski otok, where five additional grass samples were taken. I sowed alfalfa and peas in the laboratory. During the work, I examined and compared the metal concentrations of different plants from nature, the metal content in the sediment and observed the accumulation of metals on the plants sown in it. I analysed the sediment in two fractions.
With the help of the analyses I found out that it depends on the type of plant how it accumulates certain metals. The content of metals in the sediment is significantly higher than that in the plants, which means that not everything is transferred to the upper parts of the plants. As for the observed metals, I can point out that the concentration of cadmium in the sediment of Lake Ptuj is about 8 ppm, that of lead is 424 ppm and that of zinc is about 1256 ppm. The concentrations of these metals in the sediment exceed the limits specified in the Ordinance on Limit, Warning and Critical Immission Values for Hazardous Substances in Soil. Among the plants, the most cadmium was detected in grass 2 at 5 ppm and the least in horsetail, where the level is below 0.23 ppm. The highest lead concentration of 49 ppm is found in alfalfa, the lowest in grass 5 and ryegrass, where it is only 2 ppm. Zinc is most abundant in all plants, 450 ppm in grass 4 and 56 ppm in sagebrush. As with the previously mentioned metals, the permissible concentrations are also exceeded in the plants.
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