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Dokuchaev Soil Bulletin

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No 100 (2019)
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https://doi.org/10.19047/0136-1694-2019-100

5-35 1206
Abstract

The paper presents original developments on the application of WaTEM/SEDEM erosion model for large-scale mapping of erosion patterns of the soil cover in the Central Russian Upland. The share of eroded soils in the composition of soil combinations on plowed slopes was evaluated; such estimation was carried out on the basis of a statistical comparison of the calculated rates of soil losses with the results of actual soil-morphological diagnostics of the degree of chernozems erosion. The obtained relations between share of eroded soils in soil cover patterns and modelled erosion rates were used for development of the map depicting typified combinations of soils with various degrees of erosion. Comparison with detailed soil survey materials showed that the map is accurate enough for the spatial diversity and configuration of eroded soils combinations description. At the given input parameters of the erosion model qualitative changes in the soil cover structure (share of slightly-eroded soils is more than 10%) start from the threshold value of water erosion of 8 t·ha-1·year-1. With an average annual erosion of 30 t·ha-1·year-1, the share of denuded soils exceeds 50%. The developed approach seems to be promising for solving fundamental and applied problems related to the study of structural and functional organization of the soil cover of slopes and for planning the erosion control measures in adaptive-landscape agriculture.

36-52 1617
Abstract
High-quality soils are an important resource affecting the quality of life of human societies, as well as terrestrial ecosystems in general. Thus, soil erosion and soil loss are a serious issue that should be managed, in order to conserve both artificial and natural ecosystems. Predicting soil erosion has been a challenge for many years. Traditional field measurements are accurate, but they cannot be applied to large areas easily because of their high cost in time and resources. The last decade, satellite remote sensing and predictive models have been widely used by scientists to predict soil erosion in large areas with cost-efficient methods and techniques. One of those techniques is the Revised Universal Soil Loss Equation (RUSLE). RUSLE uses satellite imagery, as well as precipitation and soil data from other sources to predict the soil erosion per hectare in tons, in a given instant of time. Data acquisition for these data-demanding methods has always been a problem, especially for scientists working with large and diverse datasets. Newly emerged online technologies like Google Earth Engine (GEE) have given access to petabytes of data on demand, alongside high processing power to process them. In this paper we investigated seasonal spatiotemporal changes of soil erosion with the use of RUSLE implemented within GEE, for Pindos mountain range in Greece. In addition, we estimated the correlation between the seasonal components of RUSLE (precipitation and vegetation) and mean RUSLE values.
53-82 875
Abstract
The geochemically conjugate series of soils (Albic Podzol – Albic Podzol Gleyc – Hystosol) formed on an undulating glaciolacustrine plain in the middle taiga of Karelia was investigated. Surveys for redox conditions showed them to vary from oxidizing in automorphic soils to reducing in soils occupying accumulation-favoring locations. The geochemical coefficients descriptive of the features of accumulation and directions of migration in the studied soils were calculated and analyzed. The distribution of silicic acid and a majority of sesquioxides inside the profile of the studied soils is typical of podzols. The podzolic horizons of the soils occupying interstitial positions have a faster outmigration of elements than in automorphic soils, while their Al-Fe-humic horizons accumulate aluminum, iron, titanium and phosphorus. All the soils are deficient in a majority of microelements as compared to their background levels; very low concentrations were determined for nickel, cobalt and manganese. The content of copper and sometimes zinc is at the background level. The distribution of the studied elements across the soil profile follows the accumulation-eluviation-illuviation pattern, but the scope of variation in the migration of elements varies among topographic positions. In well-drained locations microelements are quite monotonously distributed through the lower part of the soil profile, while soils in transitional landscapes have a higher differentiation of microelements. The differentiation of the catena through lateral migration is of the transient eluviation type, i.e. soils in lower-lying positions are poorer in the studied elements than soils in automorphic positions. This pattern is due to the natural characteristics of the area: low surface slope, homogeneous sandy parent material, low humus content in soil.
83-116 918
Abstract

The aim of the study was to research the relationship of chemical and micromorphological properties of soils with the growth of Kochia prostrata. The objects of study were the soils on natural pastures of the North-Western part of the Caspian lowland. It was laid 4 soil pits (soils – light solonetz, solonetzic chestnut) with the maximum penetration depth of the main mass of roots of the studied plants. K. prostratais a very plastic forage species that can grow on soils with a wide range of morphological properties, different salt content and their chemical composition. It is revealed that on the background of almost the same content of humus and high content of exchangeable magnesium micromorphological features represent the different degree of manifestation of primary pedogenic processes – humus accumulation, leaching of soluble salts, gypsum accumulation, carbonate enrichment, solonetzization. Despite the different content of exchangeable sodium, in all soils there are fresh clay or humus-clay illuvial coatings, indicating the manifestation of the modern eluvial-illuvial redistribution of fine matter (lessivage or illimerization).

117-132 733
Abstract

The problems of radioactive contamination of biosphere with the 238U in recent years have attracted a large number of experts in various fields of knowledge. Natural radionuclides are an integral part of the biosphere. They are concentrated everywhere: in rocks, in soil, water, air and food. Various types of phosphorus fertilizers and other natural ameliorants used in agriculture are also an additional source of heavy natural radionuclides. The review describes the behaviour and migration of 238U in biosphere, which depend on various factors acting simultaneously. It is noted that the behaviour of 238U in the soil depends on the forms of its presence in it and the physical and chemical properties of the soil. The processes of sorption and desorption of 238U by different soil types are significant indicators.

133-158 891
Abstract
Technology for the production and use of new multiple slow-release fertilizers from clay-salt waste (sludge) remaining as a result of potassium fertilizers production from natural K-Mg ores, is elaborated in Perm Federal Research Center. The main processes in the technology are waste enrichment and subsequent high-temperature calcination of the enriched concentrate. As a result, the product, received the name the calcine of clay-salt sludge, was formed having the properties of multiple slow-release fertilizer and ameliorant. Laboratory and field experiments on the calcine use as a potassium fertilizer were fulfilled. The studied crops were spring wheat, barley, and potato. The experimental scheme included such treatments: control (without fertilizers), NP – background; NP + KCl and NP + calcine. The use of calcine for grain crops (wheat, barley) on the NP background promoted the yield gains by 1.7–1.9 t/ha compared with the control, the use of standard NPK fertilizers – by 1.8–2.0 t/ha, the difference was within the error of the experiment (HCP05 = 0.21; 0.38 t/ha). The content of nitrogen, phosphorus and potassium in the grain and straw of both crops in the treatments using calcine was approximately equal to the variants using standard fertilizer and significantly higher compared to the control. Differences between calcine treatments were not significant. The application of N90P90 and full mineral fertilizer (N90P90K90) contributed to the yield increase of potato tubers by 1.43–4.51 t/ha respectively. The use of unconventional potassium fertilizer – calcine on the background of NP was not inferior in efficiency to the use of traditional fertilizer – potassium chloride. The quality parameters of the potato crop (dry matter and starch content in tubers, the content of heavy metals) were also not inferior compared to the use of traditional potassium fertilizer. The use of calcine for potato and cereals in rates equal to K60-120 did not lead to deterioration of the fertility indicators of sod-podzolic soil. Upon receipt of the cinder, one can use the additional unlimited set of components. In other words, this is a conceptual model for creating new types of mineral fertilizers with desired properties for different soil and climatic conditions and crops with different requirements for mineral nutrition.
159-189 988
Abstract

Using the method of inoculation on elective nutrient media, the abundance and activity of taxonomic (bacteria, actinomycetes, micromycetes) and functional (nitrogen fixers, ammonifiers, denitrifiers of amylolytic, cellulolytic) groups of microorganisms in agrochernozems of the Stavropol region under the influence of various tillage systems – direct seeding (no-till) and moldboard plowing with the turnover of soil horizon (traditional treatment). Analyzes were carried out for such crops as winter wheat, corn, sunflower and soybean with/without application of mineral fertilizers. Traditional tillage for the majority of crops leads to increased activity of aerobic ammonifiers, cellulolytics, denitrifiers, actinomycetes and micromycetes. No-till technology, in its turn, increases the intensity of anaerobic cellulolytics and nitrogen fixers, aerobic diazotrophs and amylolytics activity. The most responsive crop, under which the biological activity of almost all groups of microorganisms increased in the no-till variant, was corn, while winter wheat contributed to the increase in the number of microorganisms in the moldboard plowing variant. The use of mineral fertilizers provoked the growth of soil biological activity under sunflower sown directly in the soil, while conventional tillage resulted in higher soil biological activity without application of mineral fertilizers.



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ISSN 0136-1694 (Print)
ISSN 2312-4202 (Online)