EN
To study the effects of anthropogenic salinity-sodicity on dehydrogenase (DHA) and catalase (CAT) activity in soil, samples were collected from the Ciech Soda Polska S.A. Plant in Inowrocław. The soils closest to the plant were assayed to determine pH, electrical conductivity(EC1:5), and enzymes activity. The soil resistance (RS) and resilience (RL) indices were computed. The soil was sampled in July and October 2015 from the plant area not covered by the recultivation treatments (locations no 1, 2, 3, 4) and the locations where the agrotechnical soil recultivation was performed (5, 6). The successive soil sampling locations (7, 8) were located in the vicinity of the plant, while the control (point 9) – beyond the impact of the plant. Soil was sampled from the depth of 0–20 cm and 20–40 cm. To compare the activity of the oxydoreductases sampled from various locations, indices were calculated to facilitate estimation of both soil processes degradation and recultivation. It has been observed that the highest value of pHKCl and electrical conductivity increased the CAT and inhibited the DH activity. RS values for the dehydrogenase activity closed to 0 for the soil from stands in the vicinity of the plant, meaning the effect of saline on soil not only in places of stored post-soda sludge, but also in the area near the Ciech Soda Polska S.A. The highest value of soil catalase RL in location no 5, 0–20 cm deep, from recultivation area suggests a correct recultivation.