SOIL TILLAGE SYSTEMS IN THE FUNCTION OF ECOLOGICAL SUSTAINABILITY

Stationary field experiment pertaining to the winter wheat in Croatia was performed during the three seasons. This study’s intention was to examine and diagnose the effect of tillage systems (TS) on soil chemical properties (soil acidity, phosphorus [P], potassium [K], and organic matter content). The TSs were as follows: CT — ploughing up to 30 cm depth, DT — disking up to 8-12 cm depth, LT — loosening up to 35 cm depth, and NT — no-tillage. The experimental design was a randomised block design in four repetitions, in which the basic TS plot amounted to 540 m2. Soil sampling for 0-30 cm soil layer was performed prior to setting up the experiment and subsequent to the three seasons with a total of 320 soil samples. Chemical analysis was performed according to standard pedological procedures. Economic indicators were calculated using economic equations and standards, whereas statistical analysis was performed with SAS 9.3 and Microsoft Excel 2016. Generated results indicate that the expressed accumulation of phosphorus and potassium appeared with a distinct vertical stratification in the systems with shallower tillage or no-tillage. At the same time, these TSs ensured the soil organic matter and soil fertility preservation. A conservable agricultural production of reduced soil tillage systems has its efficiency and vigor while providing soil degradation.