The Influence of Tillage Methods on the Infiltration in Soil

Abstract

Over the centuries, conventional agricultural practice around the developed countries encouraged extensive soil tillage. Tillage can have both favourable and unfavourable effects on different soil physical properties of the treated topsoil. If the topsoil water content is not too high or too low when the tillage is performed the short-term effect of tillage is generally favourable; the top layer cohesive strength is decreased, the total porosity is increased. Tillage implements break up the large clods, incorporate organic matter into the topsoil, reduce the weeds and prepare a seedbed. Over longer periods, tillage treatments have detrimental effects on surface soil structure such as hastening of the oxidation processes of soil organic matter due to mixing and stirring the soil and reducing the aggregating effect of the soil. When the tillage treatments are carried out especially on the wet soil, the stable soil aggregates are crushed or smeared, macro porosity is decreased and puddled soil is created. This action exposes organic matter that had been protected inside the aggregates, hastening its loss by decomposition (Brady, Weil, 1999). Some studies have shown that aggregation and the associated desirable soil physical properties (bulk density, porosity, degree of aeration, capillary water capacity and others) and hydro-physical properties related to infiltration rate decline after long periods of tilled row-crop cultivation. Le Bissonnais and Arrouays (1997) published, that the infiltration rate under rain agrees well with aggregate stability measurements and the soil structure stability declined as organic carbon declined.