Abstract:
The investigations conducted during 1998 – 2008 followed the influence of
different soil tillage systems on crop yield and soil chemical and physical characteristics. Trials
were set up in split–split plots on a typical Cambic Chernozem of clayey-loam texture, mean
humus content (3.2 %), weakly acid reaction and mean supply in mineral elements. After 11
years of experiences, ploughing to a depth of 20 cm has resulted in settling the soil layer at
depth of 19-25 cm, causing the increase in apparent density to 1.52 g/cm3, the decrease in total
porosity to 43.3 % and the increase in compaction degree until 16.2 % of the volume. In case
of the tillage system with chisel and paraplow, the mean yields obtained in the last 10 years
were lower by 2-5% (53-145 kg/ha) in wheat, by 4-5% (202-282 kg/ha) in maize and by 4-8%
(106-206 kg/ha) in soybean, in comparison with ploughing to a depth of 20 cm. At soil tillage
with chisel + disk in maize crop, the percent of hydrostable aggregates from soil, at depth of 0-
30 cm was by 15% higher, in comparison with ploughing to a depth of 20 cm. Soil tillage with
chisel and paraplow determined the increase by 5.5 mg/kg (12%) and 16.0 mg/kg (7.0%),
respectively, in mobile phosphorus and potassium content from soil, in comparison with
ploughing to a depth of 20 cm, due to improved soil physical characteristics. At soil tillage
with chisel and paraplow, the content of organic carbon from soil was higher by 0.33-0.38
g/kg, in comparison with ploughing to a depth of 20 cm.
