Effect of fluvisols tillage on their physical properties and on maize yield

The aim of this work was to determine the effect of soil tillage on physical properties and yields of grain maize in soil conditions of Eutric Fluvisol (FMm) and Fluvi-eutric Gleysol (FMG). Treatments were carried out in 1999-2002 in Vysoka above Uh river (FMm) and in Milhostov (FMG). These experimental localities are situated in central part of the East-Slovakian Lowland, approximately in altitude of 105 m and 101 m. For the localities the continental climate is typical. Eutric Fluvisol is characterized as loamy soil, middle heavy soil with content of clay particles more than 30 %. This soil is deep and good permeable in whole profile. The topsoil has light brown colour and cloddy till bean-shaped structure. Fluvi-eutric Gleysol is characterized as clay-loamy soil, heavy soil with average content of clay elements 53 %. This soil is hardly pervious in whole profile. The topsoil has lump aggregate structure with high binding ability. The coherent layer of grey clay is usually in depth of 0.8 m. The field treatments were realized without irrigation. Two soil tillage technologies were examined: conv. - conventional tillage, i.e. current way of soil by ploughing n.t. - no-tillage technology, i.e. direct sowing without tillage. Perennial forage crop was forecrop for grain maize. Doses of fertilizers (in pure nutrients): 60 kg nitrogen, 22 kg phosphorus and 93 kg potassium per hectare. Soil samples were taken in spring two weeks after maize emergence. On taken soil samples were ascertained physical soil parameters (bulk density, total porosity, maximum capillary water capacity, actual soil moisture, minimum air capacity). In field treatments grain yield of maize were determined. Obtained data were tested by mathematics-statistical methods. Variance analysis and simple regression linear analysis were used. Increase of bulk density for no-tillage variant in comparison with conventional tillage variant was determined. With this result corresponded decrease of total porosity. Grain yield of maize was significantly influenced by soil tillage, experimental year and soil type. On Eutric Fluvisol were average yields higher about 0.39 t/ha than on Fluvi-eutric Gleysol. Higher grain maize yields were obtained at conventional tillage than at no-tillage. Difference between these soil tillage technologies was 1.80 t/ha.