Studies on certain physical soil properties in long-term soil cultivation experiments on a brown forest soil in Godollo

Changes in soil physical properties during the 1997 vegetation period were studied under favourable nutrient supply conditions in a long-term soil cultivation experiment set up in 1994. The growing site was a rust-brown forest soil with moderate fertility, a shallow topsoil and moderate nutrient supplies. The present paper evaluates the effect of five soil cultivation variants on thr, total porosity, volume mass, moisture dynamics and water retention curves (pF curves) of the soil. Analysis of variance between the treatments indicated that in all the treatments differences due to the cultivation effect could only be observed in the 0-40 cm layer. The application of direct drilling and disking over a number of years resulted in significantly larger Volume mass values and lower total porosity values compared with techniques involving soil turning and loosening. It was found that the direct effect of cultivation on the pF curves could only be demonstrated at the beginning of the vegetation period in the low suction force range. By the middle of the vegetation period (June) no significant differences could be observed between the water retention values measured at different suction forces. The indirect effect of cultivation was observed at the end of the vegetation period (August). The integrated effect of soil cultivation on various physical soil parameters was characterised using measured soil moisture dynamics. Statistically significant differences were found between the soil moisture values in the ploughed layer. During the period examined the soil was driest after direct drilling, which is recommended in the literature as a way of reducing moisture losses. The highest moisture values were recorded after ploughing combined with loosening. The results prove that results obtained under different climatic conditions on different types of soil cannot be extrapolated; wherever possible, measurements should be made on the actual site.