Soil respiration was measured with SIR (substrate induced respiration) method in remediated and original soil from Austria (Arnoldstein) and Slovenia (Mežica Valley). The original soil was contaminated with PTE (potentially toxic elements), such as Pb, Zn and Cd. Remediation was carried out on a pilot remediation facility which helped washing the soil with EDTA (ethylene diamine tetraacetic acid). 80 mmol of EDTA per kg of dry matter was used for the soil of the Mežica valley and 10 mM EDTA per kg of dry matter was used for the Austrian soil. Remediated and original soil samples were compared by adding four substrates (glucose, starch, microcelulose and alfalfa sprouts) to each of them. Different substrates were sequentially added to the original soil (in order written previously) every five days. In the soil of Mežica Valley, the discrepancy can be explained by the consumption rate of the substrate between the original and the remediated soil in the last kinetic zone: glucose (0.115 µmol O2/g DM/h), starch (0,053 µmol O2/g DM/h) and alfaalfa sprouts (0.643 µmol O2/g DM/h more in original soil). Regarding microcelulose substrate, there was a greater consumption of oxygen in the remediated soil (0.298 µmol O2/g DM/h). The soil from Austria had an opposite trend. In all cases, there was a greater respiration in remediated soil: glucose (0,104 µmol O2/g DM/h), starch (0,150 µmol O2/g DM/h) mikrocelulose (0,186 µmol O2/g DM/h), alfaalfa sprouts (0,156 µmol O2/g DM/h more in the remediated soil). This is attributed to the different chemical structure of the soil and reduction of the concentration of ligand for soil rinsing and removal of PTE, which had a favorable impact on the functioning of microorganisms.
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