The offered method can be used for optimization of crop mineral nutrition (Burlakova, 1990). It is based on productivity models of basic crops grown throughout the steppe zone of the Pre-Altai soil province. The essence of the method is the change of metric values of the Content of Available Nutrients (CAN) in soil, for them to correspond to the rank of productivity of a specific crop. Indices of optimization of the basic macroelements are also calculated. It allows to reveal a discrepancy between CANs (content of available nutrients), and to estimate the optimizational amount of fertilizers required for a planned crop yield. This method has been tested on various soils used for the basic crops (Kharchenko, 2003; Sovrikov, 2005; Pivovarova, 2003), raised in the conditions of the chernozem zone. As a result, the improvement of crop yields at various agrotechnical backgrounds is about 25-50 % compared to other methods of optimization. It proves high economic efficiency of the method. The problem lies in the necessity for a quick agrochemical inspection of soils that needs to be carried out before seeding. It can be solved with the help of models of CAN, that allow to extrapolate with considerable accuracy (65-80 %) the level of nutrients in soil. Models for the content of nitrates' nitrogen N-NO3, ammonium nitrogen N-NH4, labile phosphorus P2O5, exchange potassium K2O, represent function of geochemical landscape, grain-size distribution, humus content of soil, and its taxonomic features. Dynamic models of CAN reflect functioning of soils at a microlevel under the effect of current conditions of soil formation. Parameters used in dynamic models of CAN are: the conditions of agrocenosis functioning: hydrothermal parameters of vegetation, phases of plant development, predecessors, tillage practices, fertilization and irrigation systems, etc. These models reflect the content of mineral nutrients in soil at various stages of plants' development. They can be used for the optimization of plant mineral nutrition and management of soil fertility. The suggested approach of plants' mineral nutrition optimization has not only practical application, but it is also of important ecological value, for it allows to correct unbalance of the basic biophilic elements in geochemical cycling.