Spatial and temporal variability of agrophysical properties of gray forest soils under intensive agricultural use

The variability of bulk density values in the top (0-40 cm) layer of gray forest soil was studied using a regular grid pattern (120 sampling points) on a plowland in the Vladimir Opol'e region. The sampling was performed for three years during the spring, summer, and fall seasons. In spite of the high spatial and seasonal variability of soil bulk density, its spatial distribution below 20 cm was rather stable in time. The spatial distribution of soil bulk density and water content is characterized by cyclic variations with a period about 40 m. This regularity seems to be connected with the distribution pattern of gray forest soils with the second humus horizon.