Heavy metal accumulation in the phytomass of plants in the Bolshoy Yugan River valley, Surgut District, Khanty-Mansi Autonomous Okrug–Yugra

   Processes of heavy metal accumulation in plants are increasingly attracting research attention due to the high toxicity of such substances. The pollutants accumulated in the aerial (green leaves, stems, inflorescences) and underground (roots) mass of plants cause oxidative stress associated with the production of reactive oxygen species.   In this work, we investigate the accumulation of heavy metals (nickel, lead, chromium, and cadmium) in the aerial mass of plants growing in the Surgut district of Khanty-Mansi Autonomous Okrug–Yugra.   In total, leaves from 15 plant species widespread in the studied area were collected for elemental analysis by atomic absorption spectroscopy. About 6–7 mg/kg of nickel was found in the green mass of reed canary grass and heal-all (Prunella vulgaris), which exceeds significantly the nickel amount in the aerial mass of сouch grass, marsh bedstraw, and broadleaf plantain. The aerial parts of reed canary grass and broadleaf plantain were found to accumulate more than 4 mg/kg of lead, while those of bladder sedge, сouch grass, and marsh bedstraw accumulate about 2–3 mg/kg of chromium. More than 2 mg/kg of cadmium was found in сouch grass. The results obtained were used to compile series of accumulation of elements in the aerial parts of floodplain plant species. The content of the studied heavy metals in the aerial phytomass of all studied plants, except for сouch grass, ranges within standard values, corresponding to their maximum permissible concentrations.