The influence of tillage treatments on water infiltration into soil profile

Water infiltration into the soil profile and runoff losses in arable lands are related to the condition of the top layer. The tillage treatment (included no-till) of the top layer plays a key role in changes of the hydro-physical properties, mainly saturated hydraulic conductivity (K) of the treated layer. This paper is focused on the influence of repeated tillage treatments in the same locality on K in a relatively homogeneous soil profile. The field experimental work was conducted in 1997 and repeated in 2000 after three years of repeated treatments in an experimental field of the Research Institute of Plant Production, Prague on Hapludalfs (US Classification)/Orthic luvisol (FAO). The whole experimental site was divided into four tillage treatment areas (TTA) that were maintained using different tillage treatments. A pressure ring infiltrometer (Matula and Kozáková 1997), mounted on the top of a single iron infiltration ring was used to run infiltration tests. The infiltration during the steady state flow (for a long time) was measured, evaluated and K values were calculated. Matula (2002) summarised the theoretical background for the pressure ring infiltrometer and described the final equations for evaluation of the infiltration test results. The conventional ploughing did not give any significant changes in K values after three years. Reduced till treatment and no-till treatment show a significant decrease in the infiltration rate v(t) after three years. The K value decreased approximately three times for reduced till and six times for no-till treatment. The decrease on this type of soil can cause several negative results from the aspect of surface soil hydrology and agriculture (surface runoff increase, water storage decrease, yield decrease, increase in soil compaction of surface layer, soil erosion increase).