EN
On the basis of literature data and own research, the effect of direct drilling on water retention in soil was assessed. As it results from the analysis carried out, the retention of water in soil cultivated in direct drilling-system is different from that under traditional tillage. The main reasons of the difference may be increased soil compaction, cumulation of crop residues and straw on the soil surface and accumulation of organic carbon in top soil layer under direct drilling. In the first case the effect appeared to depend on how long after the last precipitation the moisture content in soil was determined. If the measurement was taken rather shortly after rainfall, then more water was found in the top layer of uncultivated (direct drilling) than cultivated soil. In deeper layer the relations were inverse. In the following period, when the soil was drying up, the losses by evaporation were higher in more compacted soil (direct drilling) than after traditional tillage. In result, in some period of vegetation direct drilling may exert an unfavourable effect on water balance in soil. In the other cases where the above mentioned reasons of different water retention occur (accumulation of mulch in form of crop residue and organic carbon), the effect of water management was more favourable in soil under direct drilling. Moreover, expression of the soil moisure content in percentage by volume shows only its apparent increase, resulting from increased density of the soil under no-tillage.