According to the data of a long-term stationary experiment, the application of an organo-mineral system of fertilizers in combination with periodic liming significantly improves physical and chemical properties, calcium state, cation exchange capacity, and buffer capacity of soil. In this case, each next application of liming prolongs the liming aftereffect. It is important to consider these results for the use of agrochemical methods in a crop rotation.

The characteristics of the control variant of an acid nonlimed soil in which the pH values have remained stable for 40 years should be used as criteria for the maximum permissible loads of mineral fertilizers affecting the agrochemical and biological soil properties. Considerable alteration of these limiting agrochemical and biological soil properties (in the variant with NK application) leads to the soil degradation not only in the plow layer but also in the 1-m-deep layer. The application of lime, especially in combination with complete mineral fertilizer, prevents soil degradation, improves its properties, decreases the uptake of heavy metals by plants, and favors the production of ecologically clean agricultural products.

In a long-term field experiment on a medium loamy soddy-podzolic soil at the Chashnikovo Training and Experimental Soil-Ecological Center of Moscow State University, 16.6 kg/ha of strontium were added to the soil with double superphosphate (P ds ) over 41 years of its regular application (overall, 3320 kg P ds /ha were applied). As a result, the total strontium content in the soil increased by 1.1–1.3 times in comparison with the control. The changes in the content of the mobile strontium compounds were statistically insignificant. The strontium accumulation in the vetch and oats grown on the plot with the P ds application was 1.4–2.4 times greater than that in the control and in the NK variant. The strontium content in the plants was maximum on the nonlimed plots. Liming, especially in combination with application of organic fertilizers, led to changes in the soil chemical properties controlling the strontium mobility, which resulted in the lower uptake of strontium by the plants. However, the same factors predetermined an increase in the yield of the crops and a more active removal of strontium with the harvested plants. Ten years after the cessation of the fertilization, no increase in the concentration of the strontium in the perennial grasses grown on the plots with the former P ds application was registered.

Long-term application of different fertilization systems to a soddy-podzolic soil has resulted in the formation of aggroecosy stems differentiated with respect to their chemical and biological properties, humus status, the structure of actinomycetal complexes, and the bioproductivity of the soil. These differences were preserved during the period of the fertilizer aftereffect, though they became less pronounced.

The long-term application of physiologically acid nitrogen and potassium fertilizers without liming deteriorated the physicochemical properties of soddy-podzolic soil and increased the mobility of iron. The application of phosphoric fertilizers resulted in the formation of iron phosphates and other complex compounds, which decreases the mobility of iron. A specially significant decrease in iron mobility in the soil studied was observed at the application of mineral fertilizers together with liming or upon the application of mineral and organic fertilizers in combination with periodic liming. The crystallization of amorphous iron was slower in this case.

Высокопродуктивная агроэкосистема на слабоокультуренной дерново-подзолистой почве с оптимальными параметрами показателей ее плодородия была создана при длительном (40 лет) комплексном применении агрохимических средств с обязательным периодическим известкованием. Она устойчиво сохраняла положительные свойства на фоне 10-летнего последействия агрохимических средств. Длительное одностороннее применение минеральных удобрений в этом случае усиливало проявление негативных свойств данной почвы.

Periodic liming of a soddy-podzolic soil for 50 years has resulted in a considerable improvement of the indices of soil fertility, including the pH value, cation exchange capacity, buffer properties, exchangeable Ca2+ and Mg2+ percentages, the humus content, and the contents of phosphates and humates of calcium. The aftereffect of lime lasts for 11 years and ensures high levels of soil fertility if the soil is not treated with nitrogen and potassium fertilizers during this period. The increased content of phosphates and humates of calcium in limed soil is due to a considerable decrease in the intensity of leaching processes.

The complex of soil actinomycetes, along with particular agrochemical properties of soddy-podzolic soil, may serve as indicators of the status of an a,agroecosystem in the period of fertilizer aftereffects. The actual acidity of soddy-podzolic soil continued to decrease for six 6 years after the end of the application of physiologically acid mineral fertilizers, whereas concentrations of mobile phosphorus and potassium and the humus content in the soil remained relatively stable.

The long-term application of physiologically acid mineral fertilizers to soddy-podzolic soils significantly deteriorated their physicochemical properties, which resulted in the mobilization of heavy metals. The share of fungal microflora enlarged in the microbial community. The diversity of actinomyces decreased, and the humus formation became of the fulvate-humate type. Liming of acid soils in combination with the application of organic and mineral fertilizers favored the optimization of properties of soddy-podzolic soil.