Accumulation of Heavy Metals by Forb Steppe Vegetation According to Long-Term Monitoring Data

The steppes of the northern Azov Region are extremely favorable for agriculture. Thus, the foremost problem is the cultivation of ecologically safe products under conditions of technogenic pollution. We have studied the effect of aerotechnogenic emissions on the accumulation of heavy metals (HMs) in haplic chernozem, haplic chernozem (stagnic), and calcaric fluvic arenosol and steppe plants Poa pratensis L. and Elytrigia repens (L.) Nevski. of the families Poaceae and Achillea nobilis L. and Artemisia austriaca Jacq. of the family Asteraceae) according to the data from 17 years of monitoring. The accumulation of Pb, Zn, Cd, Cu, Mn, Cr, and Ni in soils and plants under the effect of power plant emissions has been established. The proportion of loosely bound compounds of heavy metals in the polluted soils is 28–52% of the total content. In the monitored plots with the highest technogenic load, the content of Pb, Cd, Cr, and Ni in the studied plants exceeds the maximum permissible level for forage. It has been revealed that HM accumulation in the aboveground part of plants and their roots depends on the amount of pollutants and the biological features of each species. The plant species of the family Poaceae accumulate less microelements in their aboveground part than Asteraceae.