HUMUS CONTENT AND STOCK IN HAPLIC CHERNOZEM AT USING DIFFERENT KINDS OF TILLAGE SYSTEMS
The article presents the study results of the influence of various treatment systems on the content, distribution and stock of humus (in the 0–20 cm layer and a meter layer) in the haplic chernozem in the southern zone of the Rostov region. It was established that contents and stock of humus in the haplic chernozem significantly depends on a way of tillage technique. On average for 4 years of research the maximum humus content in the top horizon has been revealed in the virgin soil (5,3 %) which corresponds to an increased degree of high humus content. Long–term use of dump plowing at the territory of the economy (59 years) has led to essential decrease in humus content in the soil (for 25,0 %). The long-term use of resource-saving technologies contributes to the gradual stabilization of the humus state of haplic chernozem. Application of no-till seeding increases humus content in comparison with plowing by 0.72 %, minimal processing – by 0.9 %, the degree of humification increases practically to the level of virgin soil. The humus stock in virgin soil (layers of 0–20 cm and 0–100 cm) was characterized as average (105,03 t/hectare) and high – 525,15 t/hectare respectively. Dump plowing considerably intensified mineralization of soil organic substance that has led to essential decrease in humus stock. Application of minimal and no–till technique on the contrary allows to maintain a high level of humus reserves (in the meter thickness 554,83 t / ha and 476.66 t / ha, respectively). Consequently, minimization of soil treatment in agrocoenosis creates more favorable conditions for organic matter accumulation.