Effect of various amendments on the fractions of potentially toxic elements in a contaminated environmental sample

Kateřina Vejvodová

Bakalářská práce

Abstract:

It was hypothesised that soil acidification significantly decreases the bonding of PTE in soil to the easily exchangeable fractions as well as non-labile fraction. Addition of clay to soil samples will result in greatly decreased plant available content of PTE.Clay amendments, kaolinite and vermiculite, were added at a 10% application rate to contaminated garden soil to reduce plant available metal(loid)s as well as other criterions that will reduce the impact of PTE on the environment. The garden soil samples were taken from Kutná Hora and after determining the soil properties, the samples were split into two groups; normal soil and acidified soil. The original soil was acidified by the addition of HNO3, to observe if pH would influence the adsorption of the metal(loid)s. The normal and acidified soils were prepared into 50 ml beakers in triplicates and a control, and were placed in room temperature with occasional watering. Samples were analysed three times over an eight-week period to evaluate the effect of the clays on arsenic, cadmium, lead and zinc bioavailability, pseudo total concentrations and different fractions of a BCR sequential extraction. After eight weeks, the pseudo total values remained either slightly over or under the original values, with no significant changes in absolute values. Soils amended with vermiculite, vermiculite in acidified soil and kaolinite in acidified soil had values increase in week four, only to decrease in week eight. Kaolinite in the original soil managed to decrease plant available zinc by 0.6% over eight weeks. Vermiculite, vermiculite in acidified soil and kaolinite in acidified soil decreased plant available zinc by 0.3-1.1% in week four, but concentrations increased by 0.2% in week eight. Vermiculite and kaolinite proved to reduce plant available metal(loid)s in the soil, but not to the extent as it was expected. The pH influence from the acidification of the soil was not as significant as it was expected for our experiment. The studied elements had lower concentrations in the acidified soil but conclusively values remained higher than the controls.

Keywords

soil acidification, contamination, PTE, Clay amendment

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 20. 4. 2017

Obhajoba závěrečné práce

• Vedoucí: doc. Ing. Ondřej Drábek, Ph.D.
• Oponent: Maria Vaňková, Ph.D.

Česká zemědělská univerzita v Praze

Fakulta agrobiologie, potravinových a přírodních zdrojů

Bakalářský studijní program / obor:
Sustainable Use of Natural Resources / Sustainable Use of Natural Resources