Evaluation of phyto-ameliorant influence on the structure, humus content and water regime of chernozem in the Altai Region’s Ob River area

Abstract

Currently, ecological agriculture has become widespread, and that made it possible to increase the productivity of cultivated plants through the use of scientifically based crop rotations, green fertilizers as green manure including grain crops and grain mixtures. As a result of the experiment, it turned out that in the first six months (October 2005 - April 2006) the rates of green manure mineralization were different. Thus, buckwheat decomposition was 34.5%, pea-oat mixture - 30.2% of the original state. On average, over a month, the decomposition of pea biomass reached 6%, buckwheat and pea-oat mixture - 5%. As a result, over 18 months of observations, the crops used were ranked according to the rate of mineralization, namely: pea-oat mixture, buckwheat, peas. In almost three years, the pea biomass decomposition was 81%, and the remains of buckwheat and pea-oat mixture - the average of 75%. Already in the spring, there was increase of aggregate amount of more than 10 mm (by 4-21%) and decrease of microaggregate amount by 23-38%, and the structure coefficient turned out to be higher in the variants with oats and pea-oat mixture. The maximum of valuable structural aggregates was formed during the incorporation of buckwheat (63%) as evidenced by the structural coefficient equal to 1.7. During the year of green manure action, the humus content significantly increased by 7.9% in the arable layer, and in the subsoil layer by an average of 6.5%. With a pea-oat mixture, in 8 months after incorporation of green manure, the content of total organic matter increased by 9.5%, and humus by 9.5% in the 0-40 cm layer. It should be noted that the most significant increase of humus content was achieved by green manuring of buckwheat in the summer of 2007. Ultimately, this contributed to the accumulation of moisture in the humus horizons.