Assessment of the Ecotoxicity of Ag, Bi, Te and Tl According to the Biological Indicators of Haplic Chernozem

Soil contamination with such rare heavy metals as silver (Ag), bismuth (Bi), tellurium (Te), and thallium (Tl) leads to disruption of its agricultural ecological functions. Each these has a different level soil toxicity, which affects the state recovery degree estimated by biological indicators. The work objective is assess ecotoxicity oxides nitrates silver, bismuth, tellurium, indicators Haplic Chernozem. Under conditions laboratory simulation experiment, were introduced into samples soil. for each incubation period was assessed activity enzymes (catalase dehydrogenases), intensity seed development in polluted (the length shoots roots winter wheat), microbiological total number bacteria Azotobacter sp. abundance). For 90 days, when contaminated thallium, most sensitive indicator wheat roots; nitrates, indicator. informative both chemical forms elements (silver, thallium) abundance. ecotoxic among those studied form nitrates. results study may be useful biomonitoring diagnostics soils thallium.