Glukhikh M.A., Kalganov A.A.
DYNAMICS OF SOIL FERTILITY IN THE TRANS-URALS ^{[№ 12 ' 2017]}
For many years of research, the content of humus, as the main indicator of fertility, in chernozem soils of the Trans-Urals varies depending on the conditions in a rather large range, and in the absence of erosion processes it remains in relative equilibrium. Periodically, other, directly opposite results appear in the press, but most authors start from the fact that the soil of all variants of the experiment has the same initial properties, which in nature does not exist. Therefore, it remains an open question about the dynamics of organic matter with sufficiently long-term agricultural use of soils. Long-term stationary experiments in grain-steamed crop rotation have been carried out to study the dynamics of the organic matter content in the soils of the Shadrinskaya Experimental Station. T.S. Maltsev, the northern forest-steppe of the Trans-Ural region, depending on different methods of soil cultivation and fertilization levels, selected layer by layer to a depth of 50 cm since 1969. The humus content remains at the same level for 20 years. This is also noted with very intensive tillage, and in the steam field — even twice. Some change in the humus content of the soil of only the upper horizons is noted. When dumping without fertilization, the humus content in the 0–20 cm layer remains at the same level. With soil-free tillage without fertilizers, there is a tendency for it to decrease when fertilizers are introduced and this phenomenon disappears. It was revealed that the humus content for different methods of soil treatment for almost thirty-year period, despite quite significant fluctuations in the years, remains at the same level. In the experiment using different doses of organic and mineral fertilizers, the revealed difference in the content of humus in the soil between the variants is not due to fertilizer doses, but to variegated soil cover.

Gluhih M.A., Chinyaeva Y.Z.
MICROBIOLOGICAL ACTIVITY OF SOIL AS A FACTOR OF EFFICIENCY OF STRAW USE ^{[№ 8 ' 2017]}
One of the contentious issues, especially in recent years, in connection with the decline in the number of livestock and its need for straw, is its use. In the erosion-hazardous conditions on the lungs according to the granulometric composition of soils, straw is needed, both to protect the soil from erosion, and in the form of organic fertilizer. In domestic literature, it is often considered a good organic fertilizer for other soils. When it is introduced, the biological activity of the soil, the availability of nitrogen, phosphorus and potassium to plants, the availability of labile organic substances, humus content, and the productivity of cultivated crops are increased. However, when the biological activity of the soil increases, its mineralization increases, so the introduction of more organic matter into the soil than required to maintain the humus reserve is not effective. When introducing straw into the soil, the phytosanitary situation worsens. Phytotoxins — the products of vital activity of different groups of microorganisms, leached from straw, have a negative effect on plants. In addition, bacterial and fungal colonies formed in the surface layer of the soil in the presence of plant residues are harmful, causing the spread of diseases and the accumulation of toxins. In this connection, in the chernozem soils of the Trans-Ural region, the introduction of straw does not increase the productivity of cultivated crops. What is associated with the lack of increase in productivity, requires additional research. One thing is clear: the biological activity of chernozem soils increases equally, as with the introduction of straw, and when it is burned. And the supply of plants with nitrate forms of nitrogen and mobile phosphorus does not decrease.