THE INFLUENCE OF HEAVY METALS ON THE BIOLOGICAL ACTIVITY OF RETISOLS
Environmental problems have not lost their relevance for the Non-Chernozem zone of Russia, the southern part of which belong to the Ryazan region, where in a number of areas there is a critical situation of cultural landscapes contamination of with heavy metals. The aim of the research was to assess the influence of multi-level heavy metal contamination of Retisols for the parameters of its phytotoxicity and the activity of soil enzymes. In the model experiment on Retisols, it was shown that the complex effect of heavy metals that are priority for the Ryazan region such as copper, zinc, lead, cadmium, at doses of 1.5 and 3.5 UEC (approximate permissible concentration) reduces the activity of soil enzymes and has a toxic effect on the cereal-legume mixture. In the variant of the experiment with heavy metal content of 0.5 UEC in the soil, the studied elements, mainly zinc and copper, act as chemical meliorants for Retisols depleted with trace elements. The combined effect of heavy metals (Cu, Zn, Pb, Cd) in doses of 1.5 and 4.5 UEC is phytotoxic what negatively affects the biometric indicators of the cereal-bean mixture, and also leads to accumulation in the biomass in quantities exceeding the permissible standards.