PARAMETERS OF ANTHROPOGENIC COMPACTION, SOIL STRUCTURE DEGRADATION AND CRUST FORMATION IN DIFFERENT TILLAGE METHODS

Sa？etak Research was conducted at Kri？evci College of Agriculture (N: 46o01l12ll E:16o34l28ll). Different tillage methods (variants) were studied with a smaller and larger number of secondary tillage treatments using different tools for tilling during the autumn and spring period of primary tillage. The following crops were cultivated on five different variants of soil cultivation in crops rotation: corn (Zea mays L.) in 2008 and soybean (Glycine max L.) in 2009. The aim of the research was to determine the influence of different methods and treatment times on anthropogenic compaction, structure deformation and the risk of crust formation, in order to recommend the optimal method and time of soil tillage. The following physical parameters were calculated: dispersion ratio (DR), clay dispersion ratio (CDR), flocculant index (CFI), pore coefficient (e), particle density (Gp), risk of crust formation (R) and stability parameter of structural aggregates (St). The most favourable condition of structure stability (St) was found in the variant in which primary tillage and soil preparation with seedbed cultivator was carried out in the spring, while the most unfavourable condition was found in the variant with the largest number of treatments. The highest value of this parameter and the lowest risk of soil compaction and erosion was observed after soybean growing. The highest density values of the soil particle size (PD) after corn harvesting were in the variants where the primary tillage was carried out in autumn and preparation of the soil before sowing with discs and seedbed cultivator. In both research years, the lowest risk of crust formation (R) was determined in the variant with spring primary tillage and preparation of the soil before sowing with seedbed cultivator, and the highest value of this parameter and the most favourable condition were after soybean cultivation. From the point of sustainable soil management and based on the facts mentioned above, primary tillage, as well as its preparation with a seedbed cultivator, is recommended in the spring