Comparison of denitrification induced by various organic substances – reaction rates, microbiology and temperature effect

This project aims at exploring and comparing the effectiveness of four organic substances as electron donors to improve the understanding of heterotrophic denitrification. Experiments are conducted in circulation columns using sediments without NO3- degradation capacity and natural groundwater with high NO3- concentrations due to intensive agricultural activities. The electron donors acetate, glucose, ascorbic acid and ethanol are added to these columns in three concentration steps to induce biological denitrification. Each series of experiments is conducted at room temperature and typical groundwater temperature of 10 °C to evaluate the temperature dependency of denitrification rates.