COMPOSITION AND PROPERTIES OF AGRODERN-PODZOLIC SOILS OF THE PRE-URAL PROVINCE OF THE FOREST-STEPPE ZONE

Abstract

The paper presents the results of the analysis of materials of a large-scale soil and agrochemical survey, morphological structure and properties of agrodern-podzolic soils of the Mamadysh municipal district of the Republic of Tatarstan located in the northern part of the Pre-Ural province of the forest-steppe zone. Statistical parameters of sod-medium podzolic soils accurately record the patterns of profile distribution of properties identified during the analysis of individual analytical information. Indicators of dynamic and stable properties of agrodernov-weakly podzolic heavy loamy soils are below their optimal parameters necessary for modern agriculture. Accordingly, they will be limiting factors in achieving the potential determined by the moisture availability of the territory. Agrodernovo-podzolic soils of the district in a layer of 0-20 cm on average contain 55.4 t/ha of humus reserves, in a half–meter thick – 81.1 t/ha, in a meter layer - 111.0 t/ha and 51.6; 79.3; 103.2 t/ha, respectively, in a slightly washed taxon. The degree of availability of mobile phosphorus varies according to the rounds of agrochemical examination within the limits of medium and high content. In the dynamics of potassium in the soils of the district, there is an increased content in all rounds of the agrochemical survey with a positive trend in recent years. The preservation of areas with an acidic reaction of the environment, despite the increase in liming volumes, was facilitated by erosion processes, deepening of the arable horizon, as well as the use of physiologically acidic mineral fertilizers. The actual yield of winter rye, depending on the year, has a range of fluctuations from 0.5 to 3.2 t/ha, with an average value of 2.49 t/ha and a coefficient of variation of 44.6%. Time series with the content of mobile phosphorus and potassium in soils and the yield of winter rye positively correlate with a correlation coefficient of 0.44 (mobile potassium) and 0.63 (mobile phosphorus). A reliable correlation was obtained between them. The obtained regression equations can be used to predict the yield of winter rye in the district. Soils of this type require the introduction of high doses of fertilizers and bringing the humus content of the arable horizon to its optimal values.