Assessment of the soil cover fertility on the basis of a long-term field experiment.

The model of soil cover fertility was tested during a long-term field experiment based on detailed maps of the soil cover and microrelief of the experimental field in the subzone of soddy-podzolic soils. The model includes both geometrical characteristics of the soil cover and yield values for different plots. The results proved to depend on the size of plots, number of replicates, crop rotation patterns, and the location of particular test microplots for yield measurements.