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Properties of four agricultural systems under various natural and productive conditions were compared. Parameters derived from long-term analysis and system methods were used. The purpose was to find such relationships which would confirm each other arid, at the same time, express a characteristic feature of the system to allow comparison of individual systems without regard to their structures, and to deduce their properties which would become the basis for their ecological and economic comparison.

The comparison analysis proved that the biological and energy soil potential depends on the cattle stock per hectare and, consequently, on all carbon sources. With the growing level of cattle stock per hectare, the industrial fertilizer utilization grows. Cattle stock and the cereals quantity are dependent on carbon sources (bulk feeds) in the same way.

It was confirmed that the ETA0-parameter (the ratio of silage-maize total yield to perennial fodder crops and grassland total yield), as a factor releasing the mineral nutrients in the soil by its fulvic acids, behaves as a cumulator, and it is necessary to hold it under a limit which has already been defined by Kudrna (1987, 1989a).

The OMEGA2-parameter (the ratio of the total active carbon to cereals total yield) expresses a stabilizing reserve in the whole agricultural system, and that is why it serves as an expression for stabilizers. The correlation between both these parameters (ETA0 and OMEGA2) is negative. The ETA0-parameter can result in intensive yield increase, but at the same time the stability is decreasing, the yields, and above all, the nutrient uptake become a random quantity, and are more and more dependent on changes in the meteorological conditions.

The comparison of the SIGMAC2sl/SIGMAY(s3n)-parameters (the ratio of carbon of the straw to the total yield of all carbon consumers) proved that all analysed agricultural systems show a sufficient amount of active carbon for consumers (root and tuber crops), but the SIGMAY(s3n)/SIGMAZ-parameter (total yield of carbon consumers to the cattle stock) shows that the conservative elements of land area do not allow to utilize the active-carbon surplus in agricultural systems of submontaneous regions, arid that is why the cooperation between the submontaneous and lowland regions is recommended.

The parameters used proved to be suitable characteristics in comparing analysis of agricultural systems under various productive conditions.