THE INFLUENCE OF FERTILIZATION SYSTEMS ON AGROCHEMICAL INDICATORS OF ORDINARY CHERNOZEM CARBONATE UNDER WINTER WHEAT IN A GRAIN ROTATION

Studies of different systems of organic fertilizers application on the background of different doses of complete fertilizer are held in Kabardino-Balkaria research Institute of agriculture from 1979-80 in the framework of Geographical network experiments with fertilizers. It is established that long for 30-35 years application of fertilizers increased the content of mobile forms of nitrogen, phosphorus and potassium in irrigated Chernozem ordinary carbonate in the 0-20 soil layer and in the lower horizons. 30-35 year old agricultural use of the soil without fertilizers reduced the content of humus in the soil by 0.67 to 0.69 %, nitrates, phosphorus and potassium. The observed decrease of the humus content in the soil when applying fertilizer. Found that only the joint use of organic fertilizers ? manure, green manure, straw of grain crops ? with complete mineral fertilizer ensures the preservation and reproduction of soil fertility.