Soil contamination with potentially toxic elements (PTEs) results from mining, metal extraction, other industries, and traffic. Due to the accumulation of PTEs, soils remain contaminated even after these activities stop, and the concentrations of PTEs are generally not phytotoxic, so contaminated soils are often used for agricultural purposes. This poses a risk of PTE transfer into plants and the food chain. Therefore, in 2022, we conducted a pot experiment with contaminated garden soils in the greenhouse of the Biotechnical Faculty, at the Department of Agronomy. The aim of this experiment was to determine which amendment most effectively reduces the availability of PTEs in garlic cloves and carrot roots. We considered two types of amendments – organic and mineral. To the contaminated soil from the Upper Meža Valley, we added biochar (B), compost (KO), vermiculite (V), or zeolite (Z) to reduce the mobility of lead and zinc in the soil. Each amendment was represented in both single and double doses in order to determine which was more susceptible to reduced PSE in garlic and carrot vegetables. In addition to the contaminated soil without the addition of (K), we also had a reference treatment with uncontaminated soil from Zgornji Brnik (R). All lead and zinc were determined in the edible part of the vegetable, in the pod or root. Based on the results obtained, we found that the accumulation of Pb and Zn is conditioned by the vegetable that thrives in contaminated soil, as in our experiment there was a smaller accumulation of lead and zinc in the garlic pod, while in the carrot root there was a higher accumulation. The additives only partially affected the lower accumulation of lead and zinc. There were no major differences between single and double doses of organic and mineral supplements. By comparing the limit value of lead allowed in foodstuffs, we found that carrots exceed the norm in all cases, while in the case of garlic all values are below the limit value of 0.10 mg/kg sv. m. Measurements of the height, diameter and weight of the edible part of the vegetables showed that the organic or mineral supplement had no effect on the morphological properties of the vegetables.
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