The impact of different tillage treatments on hydraulic conductivity of loamy soil

Water infiltration into the soil profile, surface runoff and soil erosion in arable lands depend on the conditions of the top layer. The tillage treatment of the top layer plays a key role in changes of the hydro-physical properties, mainly saturated hydraulic conductivity Ks of the surface layer. The aim of this study was to asses the impact of different tillage treatments on hydraulic conductivity in the locality Bohaté Málkovice. Field experimental works in this area were performed in 2009 and were repeted in 2011 on Haplic Chernozem, medium heavy loamy soil. The experimental area was divided into two parts; top layer of these plots was cultivated by applying conventional and reduced tillage treatment. Both these plots were sown with spring barley (Hordeum vulgare). For the field measurement of water infiltration into the soil was used double-ring infiltrometer (2009, 2011) and Minidisk infiltrometer (2011). Near the point were the infiltration was measured, the soil samples were always collected for laboratory determination of basic physical properties of soil (bulk density, porosity, initial and saturated water content, aeration of the soil) and saturated hydraulic conductivity Ks. For laboratory determination of Ks was used permeameter with constant gradient.For evaluation of saturated hydraulic conductivity Ks using the double-ring infiltration method was used Philip's three-parameter equation and for evaluation of unsaturated hydraulic conductivity K(h) using Minidisk infiltrometer was used Zang's method. After two years of using repeatedly applied different tillage treatments was significantly influenced saturated hydraulic conductivity Ks. The Ks value increased approximately six times for reduced tillage and more than three times for conventional tillage. Laboratory determined average values of Ks were compared with the average estimates of Ks from infiltration tests. The results were burdened by a number of errors (compaction, preferential flow). These mean values were higher for conventional and reduced tillage. Unsaturated hydraulic conductivity K(-2cm) for reduced tillage was higher, for conventional tillage decreased approximately three times.