RESUMEN
Peat reserves of the Russian Federation are estimated at more than 170.0 billion tons, it makes more than one-third of theworld resources. The use of peat as a component for the preparation of composts is an important factor in increasing theproductivity of agricultural ecosystems. During two cycles of four-course crop rotation ‘potatoes – barley – annual grasses– winter wheat’, we studied the influence of lowland peat, composted peat-poultry manure, cattle manure, their combinedapplication with mineral fertilizers on soil physicochemical properties, nitrifying and cellulosolytic activity of soil andproductivity of crop rotation. Application of cattle manure and composted peat-poultry manure contributes to the increase inthe content of humus in soil by 0.07-0.16%, when combined with mineral fertilizers – by 0.14-0.22%, respectively. Onaverage, the highest yield was noted in the variants with cattle manure and composted peat-poultry manure – 10.75-12.13 tha -1 of grain units (g.u.), while in the check (without fertilizers) it was 8.03 g.u. (t ha -1). That is why peat is more profitableto use in the form of composts, especially as a component of composted peat-poultry manure