The Influence of the Degree of Saturation of Crop Rotations with Alfalfa ( Medicago Sativa L.) and Winter Wheat ( Triticum Aestivum L.) with Ncp on the Accumulation of Plant Mass and Nutrients in the Energy Storage System of Soil Content in the Western Precaspian

The energy storage system of soil maintenance in the irrigation landscapes of the Western Precaspian is based on the use of the second half of summer for the formation of a natural crop phytocenosis (NCP) and plowing it for green fertilizer. The article deals with the formation of plant mass in grain-grass crop rotations, the concentration and accumulation of nutrients in it. The degree of saturation of alfalfa ( Medicago sativa L.) and winter wheat ( Triticum aestivum L.) with natural crop phytocenosis (NCP) crop rotations ranges from 0 to 100%. The most productive of the studied crop rotations is a four-field with one output field of alfalfa and three fields of winter wheat, after harvesting which in the second half of summer a NCP for green fertilizer is formed. In this crop rotation, 97.4 t of agricultural products were produced on 1 ha of the crop rotation area, including 30.2 t/ha of its non-alienable part from the soil. Accordingly, the removal of N, P2O5 and K2O from the soil increases. The proportion of the returned amount of nutrients from the phytomass inalienable from the soil was (%): N-17.7; P2O5 and 45.3.