Evaluation of the impact of soil contamination with mercury and application of soil amendments on the yield and chemical composition of Avena sativa L.

The purpose of this study was to determine the effect of soil contamination with Hg on the yield and chemical composition of Avena sativa L. Mercury was incorporated into soil in amounts: 0, 50, 100 and 150 mg Hg·kg^-1of soil. Zeolite, lime and bentonite were used to alleviate the soil contamination. Plants cultivated in Hg-polluted soil showed growth inhibition even in the presence of bentonite, lime or zeolite. Under elevated doses of Hg, the yield of aerial mass and roots decreased. The soil amendments mitigated the adverse effect of contamination, with lime and bentonite having a more beneficial influence on the yield than zeolite. The incremental contamination with mercury led to an increase in the content of Hg in the biomass of the plants. A much higher content of Hg was found in roots than in aerial parts. The inactivating substances applied to soil to some extent limited the increase in the content of this metal in all plant organs. Lime proved to be most effective in this regard. An increase in the soil contamination with mercury caused an increased content of nitrogen and potassium in plant organs and a decrease content of phosphorus.