EN
Activity of the enzymes can give information on the kind and duration of the effects of pollutants on the metabolic activity of soil. Results of studies on the dehydrogenase activity in soils experimentally contaminated with diesel fuel, with and without modification used in investigation over biodégradation process (including fertilization, stirring and inoculation) were presented in paper. Studies with two rates of pollution were carried out for soils of various organic matter content and different soil particle size grading. Dehydrogenase activity was determined with TTC (2,3,5-triphenyltetrazolium chloride) as a substrate. Increase of dehydrogenase activity was found in the soils that were treated with diesel fuel. Regardless of pollution rate, usually higher activity was recorded in sandy soil. Variance analysis confirmed the highly significant influence of applied modifications on increase of the enzymatic activity in relation to not modified object.