Assessment and Forecast of Soil Conditions of the Central Ciscaucasia and the Caucasus with Chromium Contamination

Abstract

Laboratory simulation of pollution with chromium (VI) oxides of 11 main types and subtypes of soils in the Central Ciscaucasia and the Caucasus was carried out: ordinary chernozems (Och), leached soil (Ls), podzolic soil (Ps), modal soil (Ms), redzina soil (Rs) , dark gray forest soil (Dgfs), slightly unsaturated brown forest soil (Subs), mountain-meadow soddy soil (Mmss), soddy-torfy soil (Sts), chernozemic soil (Chs), mountain meadow steppe soil (Mmsts). Impact analysis of 100, 1000 and 10000 mg/kg of chromium on the most sensitive and informative indicators of soil conditions (number of bacteria, enzyme activity, plant growth and development) and ecological functions of soils were performed. Regional ecologically safe concentrations of total chromium in the studied soils were established: Chs – 85 mg/kg, Ls, Och, Dgfs, Subs, Sts – 110 mg/kg, Rs – 115 mg/kg, Och – 120 mg/kg, Mmss – 125 mg/kg, Ms – 135 mg/kg, Mmsts – 140 mg/kg. Predictive deterioration maps of the biological state and violation of the ecological and agrarian soil functionality in the Central Ciscaucasia and the Caucasus in case of contamination with concentrated chromium were developed, indicating a very high environmental hazard of chromium.