К вопросу территориальной неоднородности обменной кислотности серых лесных почв Северного Зауралья

Abstract

The article presents the results of statistical processing of a large array of data on the exchange acidity of gray forest soils of the Northern Trans-Urals. The aim of the research was to study the territorial heterogeneity of potential acidity and to identify the direction of modern development of all subtypes of gray forest soils. The statistical assessment was based on data on 96 sections of light gray, 111 - gray and 123 sections of dark gray forest soils. All sections were laid in virgin areas in the period from 1965 to 2020. It was found that the gray forest soils of the Northern Trans-Urals differ from their European counterparts by significantly lower exchange acidity. The average рНKCl value in light gray forest soils is 5.1 units with a range of variation from 4.5 to 5.9 units. Slightly acidic soils (5.1-5.4 units) account for 65% of the sample. In the gray forest soils of the Northern Trans-Urals, the proportion of slightly acidic soils and those close to neutral reaches 85%, and only the remaining part has рНKCl values in the range of 4.6-5.0 units. The average value of exchange acidity in dark gray forest soils in the region is 5.7 units, which corresponds to the category of close to neutral. The range of pH values is quite wide – 4.5-6.5 units, with a coefficient of variation of 8%. The absence of a strong expression of metabolic acidity in the gray forest soils of the Northern Trans-Urals is due to the containment of the podzolic process due to the presence of a close occurrence of calcium carbonates. Statistical analysis also showed that light gray forest soils are gradually acidified due to the very deep occurrence of carbonates. Gray and dark gray forest soils follow the path of the sod process with a gradual decrease in potential acidity due to the formation of a periodically flushing type of water regime. Keywords: FERTILITY, VARIABILITY OF PROPERTIES, PODZOLIC PROCESS, MOBILE ALUMINUM, ACIDIFICATION, EXPANSION OF ARABLE LAND, SOIL COVER, WESTERN SIBERIA