Dark-humus soils on the updated soil map of Russian Federation scale 1 : 2.5 M

The dark-humus soil type was included in the updated legend of the Soil Map of the Russian Federation at scale 1 : 2.5 M, converted to the system of Soil Classification of Russia. The soil profile starts with the dark-humus horizon gradually merging to the parent rock; any mid-profile diagnostic horizons are absent. Large areas of dark-humus soils are found in the forest-steppe, steppe and taiga zones of the European Russia, Western and Central Siberia, in the Trans-Baikal region, the Altai-Sayany Mountains, and the Caucasus. The type of dark-humus soils comprises both mesomorphic soils (of normal moisture conditions) and soils with additional surface or ground-water moisture. The main prerequisites for the formation of dark-humus soils are, on the one hand, the climatic conditions favorable for the dark-humus horizon formation, and, on the other hand, parent material - mostly derivates of hard rocks, restricting the development of mid-profile diagnostic horizons. In the updated map, the following initial legend units are partially or completely converted to dark-humus soils: several units of chernozems, dark-gray forest and gray forest non-podzolized soils, soddy-taiga base-saturated and slightly unsaturated soils, several mountain soils, a significant part of soddy-calcareous soils, as well as some mountainous forest-meadow soils. The diversity of dark-humus soils subtypes is determined by secondary carbonate features, weak signs of clay accumulation and podzolization, alteration of the mineral mass, gley and cryogenic phenomena.

The impact of pine self-afforestation on podzolization process in semi-natural grassland areas of Volyn Polissya (Ukraine)

Background. Several theories have been proposed to explain the podzolization process. Currently, the role of organic matter in both weathering and immobilization in the illuvial horizon is clearly stated. The origin of soil organic matter and, accordingly, the various mechanisms of its influence on the soil material, create the basis of these theories. We assume that in the base-poor sandy soils under rich herbaceous vegetation with a well developed sod layer, the process of podzolization may also depend on CO2 soil formation agent . Materials and Methods. Four localities along a Pinus sylvestris L. self-afforestation chronosequence with pine stands of 10, 20, 40 yrs and an adjacent semi-natural grassland area were investigated in order to determine the patterns of podzolization process on sandy glacial till deposits. Soil pH, exchangeable base, soil cation exchange capacity, total content of soil organic carbon, amorphous Fe, Si and Al and total contents of Al, Fe, Mn, Zn, Cd, Pb, Cu, Co, Ni, Na, K were determined. Statistical analysis of the results was performed using LibreOffice for Linux. Results. During the pine succession, a previously well differentiated into horizons podzolic soil under the grassland vegetation community gradually degrades. Previously well-defined albic and spodic diagnostic horizons disappear, the soil profile becomes more acidic, the soil organic carbon, the base cation content and the base cation saturation decrease, the leaching rate of aluminium and iron increases. Secondary podzolization features in the soil profiles were detected 40 years after the onset of afforestation. The podzolization has not been intensive enough to develop fully fledged albic and spodic diagnostic horizons over such a short period. Conclusions. Based on the obtained soil morphological, physical and chemical properties, three most important agents of podzolization are proposed as principal for the studied area. The main gent under pine forest is fulvic acids that are produced during coniferous litter decomposition. Low molecular weight organic acids and carbon dioxide produced to the rhizosphere by roots and a root associated microbiota are mainly involved in the podzolization process under the grassland ecosystem.

Content and Distribution of Organic And Inorganic Carbon in the Urban Soils of Rostov Agglomeration

The content and distribution of organic and inorganic carbon along the profile in the soils of the Rostov agglomeration are considered. The results obtained on a TOC-L CPN Shimadzu carbon analyzer are evaluated using Student's t-test. The groups of some horizons of native soils AU rz, AU, BCA, C, as well as their buried analogues [AU], [BCA], [C] were compared. The analysis of the urbic horizons was carried out taking into account their particle size distribution, previously dividing into horizons clusters - heavy URh and light URl. In the [AU] horizon of soils buried under the anthropogenic stratum, a statistically significant decrease in the organic carbon content is observed, compared to the AU horizon of natural analogues. The middle part of the profile - the BCA and [BCA] horizons - is characterized by the greatest similarity in carbon content, both organic and inorganic, which suggests the lowest anthropogenic impact on these horizons. Significant differences in the inorganic carbon content in the comparison pair - horizons C and [C] are shown, and its content is higher in natural analogues (horizons C). The data analysis of the urbic diagnostic horizons did not reveal any significant regularities because of the high degree of variation of this indicator due to the genesis peculiarities of the anthropogenically transformed stratum.

Solos Em Carste Tropical, Desenvolvimento Pedogenético E Comportamento Hidrológico: Uma Revisão Teórica.

Este trabalho teve como objetivo reunir informações sobre comportamento pedogenético e hidrológico em áreas de rochas carbonáticas de clima tropical. A execução desta pesquisa foi embasada em artigos científicos indexados, nacionais e internacionais, como também em livros, teses e dissertações relevantes para o tema proposto. O solo é um sistema multifásico, e os seus aspectos morfológicos e constitucionais atuam facilitando ou dificultando a permeabilidade da água, assim cada horizonte pedológico funciona como um mecanismo em um mesmo perfil de solo. Os fatores físicos/químicos da água também atuarão contribuindo para a classificação dos grupos hidrológicos de solo. No Brasil, a Embrapa realizou classificações dos horizontes diagnósticos, dos grupos hidrológicos e dos tipos de solos, baseada em autores internacionais, adaptadas às condições tropicais. Mas as áreas cársticas, que representam um percentual de 20% da superfície terrestre, podem apresentar condições particulares para a formação de solo e para o comportamento hidrológico, podendo incluir zonas locais de alta permeabilidade, fuga de água subterrânea e eliminação de resíduos insatisfatórios. Solos de ambientes cársticos são mal desenvolvidos, apresentam argilas avermelhadas de baixa atividade normalmente. No Brasil os estudos deste tipo de ambiente são escassos, mas alguns trabalhos desenvolvidos em áreas cársticas trazem algumas informações básicas sobre os solos. As pesquisas encontradas que trouxeram informações dos solos em carstes, foram plotadas no mapa brasileiro. A pesquisa demonstrou que há um gap de informações para o desenvolvimento pedológico em áreas cársticas, mas é possível fazer associações entre estas classes de solo a outros ambientes, incluindo o comportamento hidrológico.Soils In Tropical Karst, Pedogenetic Development And Hydrological Behavior: A Theoretical Review A B S T R A C TThis work aimed to gather information on pedogenetic and hydrological behavior in carbonate rock areas of tropical climate. The execution of this research was based on indexed scientific articles, national and international, as well as on books, theses and dissertations relevant to the proposed theme. The soil is a multiphase system, and its morphological and constitutional aspects act to facilitate or hinder water permeability, so each pedological horizon works as a mechanism in the same soil profile. The physical / chemical factors of the water will also act contributing to the classification of soil hydrological groups. In Brazil, Embrapa carried out classifications of diagnostic horizons, hydrological groups and soil types, based on international authors, adapted to tropical conditions. However, karst areas, which represent a percentage of 20% of the earth's surface, may present particular conditions for soil formation and hydrological behavior, and may include local areas of high permeability, groundwater leakage and unsatisfactory waste disposal. Soils in karst environments are poorly developed, with reddish clays of low activity normally. In Brazil, studies of this type of environment are scarce, but some studies carried out in karst areas bring some basic information about the soils. The researchers found that brought information on soils in carstes, were plotted on the Brazilian map. Research has shown that there is an information gap for pedological development in karst areas, but it is possible to make associations between these soil classes and other environments, including hydrological behavior.Keywords: Soil Hydrological Groups; Tropical Soil; Karst.

GPS Based Soil Profile Study in Respect to Morphological and Nutrient Analysis in Pedon of Ganjam District

GPS based two pedons- one each from up and medium land during dry season, studied in the field & analysis done in the laboratory. The difference in properties between two pedons was mostly due to lateritic and basaltic parent material in pedons. The morphology of mineral soils explains the evolution that occurs in the soil body during the process of soil formation, which is predominantly influenced by the parent material and climate. Determination of epipedon and endopedon of diagnostic horizons through description and interpretation of soil profile properties is the basis of land classification, as the knowledge of soil properties, capabilities, and utilization. The results of the study found that, based on its morphological and chemical characteristics, the soil in pedon 1 had brighter colors, higher micronutrient availability, and a thicker horizon compared to the soil in pedon 2. Meanwhile, the pedon 1 is light texture, crumb structure and pedon 2 is heavy texture and sub angular blocky structure. Both the form of density in two pedons was increasing downwards & the value were of a typical mineral soils, but the pore space showed a reverse trend on confirming the compactness and aging of soils towards subsurface horizons. Same results tendency found in micronutrients analysis where pedon 1 rich in micronutrients as compare to pedon 2.

Development of the basic soil classification of Vladimir Fridland in the classification of soils of Russia 2004/2008

The basic three-component classification system of soils of the world was published by V.M. Fridland in 1982, and its profile-genetic component was taken as a basis for the classification of soils of Russia (1997– 2004–2008). Unlike the former systems, in that of Fridland the priority is given to soil properties, and this conceptual background is transferred into the new Russian system. The substantive-genetic principles of both systems are implemented in diagnostic horizons and genetic properties; both systems have similar hierarchy of taxa, nomenclature, keys. Changes introduced in the classification of soils of Russia derive either of proposals forwarded in the course of its application, or of information accumulated. They concern the improvement of definitions and introduction of new diagnostic elements; however, the main principles are preserved in the existing and forthcoming versions.

Pedogenesis in the Barreiras Formation Under Climates of Rio Grande do Norte, Brazil

In Brazil, the state of Rio Grande do Norte has an important coastal zone and coastal Tableland areas along the Barreiras Formation, but there are few studies to locate and characterize soils with cohesive character. Therefore, this work was carried out to characterize pedons in the western and eastern mesoregions of the state, located in the Barreiras Formation and with different climatic conditions. The profile description and sample collection were carried out in March and April 2016. The characteristics of the profile identified were the sequence of horizons and their depth, soil color, texture, structure, consistency, and transition between horizons. The physical analyzes were of soil density and texture. The chemical analyzes consisted of: pH in water and in KCl, contents of available P, Na+, K+, Ca2+, Mg2+, potential acidity, and total organic carbon. Indices obtained were: base sum, effective cation exchange capacity, cation exchange capacity at pH 7.0, base saturation, exchangeable aluminum saturation, and exchangeable sodium percentage. The profiles were classified up to the fourth categorical level. The mineralogical assembly was identified in the clay fraction of the diagnostic horizons. The identification of the minerals was performed by X-ray diffraction. The pedons of the two regions presented distinct characteristics and pedogenesis, occurring laterization in the pedons of the western mesoregion and podzolization in the pedons of the eastern mesoregion, both without presence of cohesive character as a diagnostic attribute.