The present study includes the results of comparative investigations of aggregate composition and water stability of structural aggregates in humus horizons of non-calcareous rendzina under native forest and pasture vegetations and the same rendzina utilized long-term as arable field. The results show that aggregate composition and water stability of structural aggregates in the cultivated non-calcareous rendzina are significantly impaired due to a long-term anthropogenization.

The paper includes the results of determination of Atterberg plasticity limits of arable (0-25 cm) and subarable (25-50 cm) horizons in 53 pseudogley profiles from the community of Ub. On the basis of performed laboratory investigations, it has been found that the pseudogley belongs to the group of moderately plastic soils, with plasticity index higher than 17. In the arable horizon, average moisture at the plastic limit is about 20%, and in the subarable horizon - about 19%.

Long-standing utilization of agricultural machines in agricultural production leads to a significant increase of compaction in noncarbonate, slightly smonitza - like meadow black soils, in the Kolubara river valley. A substantial increase of compaction in the investigated soils was found in arable and subarable horizons down to the depth of 30 cm.

The aim of this research was to figure out certain limitations of methods for drain spacing determination application in unsteady-state of flow rate to the drains in the eugley soil. The well-known Glover-Dumm method was taken in this analysis. The analysis was based on the results of drain discharge and water table depth measurements. Measurements were carried out on the experimental field.