In Uzbekistan soils, the humus content has decreased approximately 50% and this process is increasing. The humus decrease leads to soil degradation and diminishes the efficiency of antierosion measures and technological methods. If this process continues, the soil will lose its main qualities. The use of composts, made from manure and domestic city waste, may play an important role in the resolution of these problems. Annualy, Uzbekistan generates about 30 million m3 of city hard domestic waste. One million tons of hard domestic waste contains 360 thousand tons of waste foodstuffs, about 160 thousand tons of paper and cardboard, 55 thousand tons of cloth, and 45 thousand tons of plastic. In the present time, reducing organic fertilizer and increasing city hard-domestic waste is under consideration. A criterion for using organic fertilizers with hard domestic waste is the content of heavy elements, such as Zn, Cu, Ni, Mn, Cr and others, and humus acids. From these wastes, composts rich with elements of feeding can be prepared and used as organic fertilizers. The use of these wastes not only increases the quantity of organic matter, but promotes the protection of the environment from pollution. When these composts are used, the erosion processes in soil decreased and the agrochemical and agrophysical qualities improved, promoting the activity of biological processes in the soil. Composted manure with city hard-domestic waste provides the soil with needed macro- and microelements. Therefore, the use of composts improves assimilation feeding elements by plants, strengthening their growth and development and decreasing the quantity of mineral fertilizers used, which decreases the economic expenses. Thus, the preparation of composts from agricultural and city hard-domestic waste significantly increases the humus content in soil.
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