On the question of stabilization of humus conditions of arable chernozyoms due to plowing straw of grain crops

Now practically all arable chernozyoms experi-ence the strongest anthropogenous strain in the form of reduction of mass of the arriving vegetable remains, high aeration of humus layer and change of the nutritious mode. The agricultural enterprises, proceeding from an economic situation, intentional-ly refuse using organic fertilizers on the fields re-mote from the farms. Therefore there was a serious problem of dehumification of arable soils and the decrease in fertility in general. The straw of grain crops can become the only cheap organic fertilizer capable to correct current situation. Studying the possibility of stabilization of humus condition of chernozyom soils of forest-steppe zone of Trans-Urals at the expense of plowing the straw of the grain crops which grew on various agroback-grounds was the purpose of the study. The re-searches were conducted in the south of Tyumen Region, on the station of State Agrarian University of Northern Trans-Urals. As a result of long-term researches (22 years) it was established that plow-ing the straw of grain crops grown up without min-eral fertilizers led to annual loss of 1.1 tons of hu-mus in the layer of 0-40 cm of the arable cher-nozyom, the maintenance of humus for 22 years decreased from 6.61 up to 6.12 % of the soil mass. Introduction of mineral fertilizers on the planned productivity of grain crops of 3.0 and 4.0 t/hectare of grain provided positive balance of soil organic substance, i.e. the annual increase of humus in the layer of 0-40 cm made 1.3 and 1.0 t/hectare, respectively. Receiving the crop over 4.0 t/hectare of grain at the expense of mineral fer-tilizers increased microbiological activity of the soil which completely mineralized the vegetable re-mains and part of humus substances. Annual loss-es of humus, despite twice increased mass of plowed straw, made 1.2 t/hectare.