The structure of the cultivated areas serves as the basis for the system of crop rotation, the main link in modern farming systems. The structure of sown areas and the system of crop rotations as the fundamental links of the farming system have close direct correlations and feed-backs with all other links of the farming system. On the one hand, they are fundamental, first of all, for organizing the soil protection and nature conservation of the territory, since in each farm the sown areas of agricultural crops on arable land prevail over the area of other agricultural lands. On the other hand, the system of crop rotation, which is developed on the basis of the promising structure of sown areas, is the basis for other links of the farming system. For more efficient use of arable land, increasing the yield of major agricultural crops, meeting the needs of farms with crop production, improving soil fertility, it is necessary to change the structure of sown areas taking into account the specific agro-climatic conditions of the steppe zone. There are two subzones in the considered zone: arid and moderately arid one. We have substantiated and optimized the structure of cultivated areas in order to increase soil fertility, ecological balance and productivity of agricultural landscapes for these two sub-zones of the steppe zone. For the arid sub-zone, in the structure of sown areas, winter and spring crops should occupy 51.7%, legumes – 9.8%, fodder – 12.5%, industrial – 21%, vegetables – 5%. For the moderately arid sub-zone in the structure of sown areas, winter and spring crops should occupy 42.0%, legumes – 10.3%, corn for grain – 13.7%, fodder – 10.5%, industrial – 17.0%, vegetables – 5%, potatoes – 1.5%.
«MELILOT BIENNIAL» AS AN IMPROVER OF SOIL FERTILITY IN THE DRY-STEPPE ZONE OF THE LOWER VOLGA REGION
