This study aims to evaluate the impact of different tillage systems on water conservation and penetration resistance in Stagnosols on slopes. Three tillage systems were evaluated during a long-term experiment in Central Croatia in a period from 2011 to 2014, in order to identify sustainable land management practices: control treatment (CT), ploughing and other seedbed layer preparation up and down the slope; ploughing across the slope (PA) – to 30 cm, other operations depending on the crop, also across the slope; and ploughing across the slope (30 cm) with subsoiling (SUB) to 50 cm. Penetration resistance and soil water content were measured each investigated season during five terms to a depth of 60 cm. Tillage systems significantly influence soil water content and penetration resistance, but the results showed great temporal and vertical variation in each investigated season. The results also showed that in low quality Pseudogley deep loosening is required because of the inability of these soils to recover naturally. The hardness of these soils decreases after tillage, or when the moisture content increases, so the period with potentially limiting soil impedance is shorter in systems with subsoiling than in conventionally tilled soils. Fallow has been effective in reducing soil strength in non-traffic areas and increasing soil moisture content. When comparing cropping variants it was established that only a system including subsoiling ensures higher moisture content. Results indicate that since soil water content and penetration resistance were adversely affected, subsoiling should be applied continuously in Pseudogley sites in the hills. Generally, soil resistance increased with time from the date of primary tillage. Although penetration resistance values increase after tillage, the differences were attributed to temporal variation of soil water content. In this study soil moisture condition is presented as a more important factor for soil resistance than the time between primary tillage and measurements.

Compaction, penetration resistance, soil water content, tillage systems

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia