| Abstract [eng] |
Donatas Riškus. Master ‘s thesis. Soil contamination by heavy metals in the areas of former pesticide storage facilities. 2022. Supervisor Dr. Ilona Kerienė. The purpose of this thesis is to assess the pollution of soil and water bodies with heavy metals in the territories of former pesticide storage facilities and to provide recommendations for pollution management. Stages of research: (1) To investigate the concentrations of heavy metals in soil and water bodies in four areas. (2) To analyze the distribution of heavy metals in soils of different depths, surface water. (3) Assess the condition of the soil in the area of former pesticide storage facilities and provide recommendations for pollution management. Research methods. Soil samples were taken at 4 different locations with a hand drill. Soil samples were taken at two depths: 0-20 cm, 20-40 cm. Surface water is sampled with a shovel. The samples taken were mineralized in acid. The determination of heavy metals in the samples was performed by optical emission spectrometry. Spectral analysis was performed on an iCAP7400 Duo. Comparative analysis of heavy metals in soil and surface water was performed using R and RStudio packages. Research results. The study showed that the soil and surface water of the former pesticide storage areas are contaminated with heavy metals - chromium, nickel, tin - according to the limit values for chemicals set for the soil and surface water of the group of sensitive areas I-IV. As all cases were isolated, pollution is not associated with former pesticide facilities. Analysis of the distribution of heavy metals at different soil depths showed that chromium, nickel, and cobalt tend to accumulate in the deeper soil layer. Seasonality affected the concentrations of barium, cadmium, copper, molybdenum, stibium and iron in the soil. Higher pollution of surface water with barium, chromium, copper, nickel, selenium and tin metals is possible during the colder season. Their concentrations were significantly (p <0.05) higher in the autumn season compared to the spring season. Conclusions. The study showed that the areas of the former pesticide storage facilities are not significantly contaminated with heavy metals and can be used for economic purposes. However, chromium, nickel and cobalt are associated with a higher risk of contamination of soil and surface water with heavy metals. In the case of anthropogenic pollution, these metals can contaminate the soil to a depth of 40 cm and leach into surface water. |
