Relationships between the Size of Aggregates,Particulate Organic Matter Content,and Decomposition of Plant Residues in Soil

Eurasian Soil Science - The distribution of total organic matter (Corg), particulate organic matter (CPOM), and potentially mineralizable organic matter (C0) in mega- (10–5 and 5–2 mm),...     

Investigation of the resistance of bacterial pathogens of gastrointestinal and respiratory diseases of piglets to antimicrobial drugs

The level of resistance of E. coli, S. cholerae suis, S. typhimurium, Str. pneumoniae, and P. multocida microorganisms to ampicillin, oxytetracycline, gentamicin, cefazolin, ciprofloxacin, levomycetin, and nitrofurans and the dynamics of its development over the years are given. The majority of cultures were resistant to six drugs. Ciprofloxacin, to which the majority of tested pathogens are highly sensitive, is recommended for treating animals.     

Specificity of the chemical and mineralogical composition of salts in solonchak playas and lakes of the Kulunda steppe

The chemical composition of water in 44 lakes of the Kulunda steppe has been studied. It is shown that solute concentrations in different lakes vary from 1 to 390 g/l. Four chemical types of the water salinity—chloride, sulfate, chloride-sulfate with the presence of sodium bicarbonate, and sodic waters—are distinguished. The nature of the water alkalinity has been studied in 12 lakes. In the lakes with neutral chloride and sulfate salts, the total alkalinity does not exceed 16.56 meq/l. In the lakes with the presence of soda, it reaches 189 meq/l. In sodic waters, the total alkalinity varies from 600 to 1504.6 meq/l. In the latter case, the water alkalinity is conditioned by the presence of soda and borate salts. Salt minerals in the bottom sediments and in the salt crusts of solonchakous playas around the lakes are represented by halite, calcite, dolomite, and thenardite. In two salt crusts, the presence of soda and trona has been diagnosed.     

New processes of microbial transformation of nitrogen in soils as a source of greenhouse gases

DNA isolation from soil samples and amplification of fragment of a key gene of nitrification, archaeal and bacterial amoA, revealed presence of the product in all investigated soil samples. Characteristics of ammonia-oxidizing microbial communities in agrocenoses and undisturbed soil were determined. Bacteria were predominant in agrocenoses (at circum-neurtal pH), whereas the share of representatives of domain Archaea (phylum Thaumarchaeota) increased in prokaryotic ammonia-oxidizing complexes of undisturbed forest ecosystems (at low pH). It was demonstrated that the contribution of taumarhaea in nitrous oxide emission from gray forest soil may reach 20–25%.     

Valentin Dmitrievich Tonkonogov is seventy

Jubilees

Valentin Dmitrievich Tonkonogov is seventy     

Ecological niches of major soil types in Russia: Geographical aspects of the new Russian soil classification system

The factors of soil formation are not directly taken into account in the new profile-genetic Russian soil classification system; they are not reflected in the names and diagnostics of the soils. At the same time, as well as in many other modern soil classification systems, including the American Soil Taxonomy and the WRB system, the choice of the diagnostic criteria, the establishment of the relationships between them, and the setting of the quantitative boundaries between the soil taxa are based on our perception of soil geneses with due account for the factors of soil formation. In contrast to the ecological-genetic soil classification system of 1977, information on the factors of soil formation in the new system is encoded in the properties of the soil horizons. In some cases, this is insufficient for the definite geographic localization of soils and complicates the practical application of the new classification system. In this context, information on the ecological niches of soil types was included in the field manual on soil correlation-an abridged version of the soil classification system published in 2008—in the form of special tables developed for native and agrogenic soils. The analysis of these tables made it possible to outline certain geographic regularities in the distribution of soil types belonging to the trunk of postlithogenic soils.     

Estimation of the Biogenicity and Bioactivity of Gleyed Agrogray Nondrained and Drained Soils

Eurasian Soil Science - A comparison of the biological activity and biogenicity of drained and nondrained gleyed agrogray soils (Luvic Greyzemic Stagnic Phaeozems) of Moscow oblast has been carried...     

Soil-genetic zoning: Principles, goals, structure, and applications

The soil-genetic zoning proposed, unlike the known scheme of soil-genetic zoning, is based on the analysis of soil properties and soil-forming processes. Its objective is to interpret the soil cover in the format of the substantive-genetic soil classification of Russia (2004). The units of the soil-genetic zoning are distinguished according to the manifestations of horizon-forming processes: the main processes determining the principal trend of pedogenesis and the soil profile composition at the first level and the additional processes (forming the associated soils) serving as criteria for distinguishing the units at the second level. The results obtained allow considering this investigation as an experience of a new interpretation of a small-scale soil map and its analysis from two positions: the geography of the soil-forming processes and the complexity of the soil cover. The soil-genetic zoning has been carried out on the basis of the State Soil Map sheets; it can be an instrument for the conversion of the map??s contents into the substantive-genetic soil classification of Russia (2004).     

A new classification system of soils of Russia: Preliminary results of discussion

The first version of the profile-genetic classification system of the soils of Russia published in 1997 was discussed by soil scientists and verified in different ways. As a result, a number of changes and additions were made in the new version of 2004. Many comments concerning this version were obtained from the regional divisions of the Dokuchaev Society of Soil Scientists, as well as from specialists (papers in Eurasian Soil Science and discussion on the Internet). The authors of the classification system consider it reasonable to analyze the results of the discussion concerning both the principles and nomenclature and some groups of soils.     

Comparison of Micromorphometric Characteristics of Aggregates from Noneroded and Moderately Eroded Typical Chernozem in a Laboratory Experiment

Eurasian Soil Science - The aim of this study was to develop an approach to assessing the impact of rill erosion on aggregates of typical chernozem aggregates in a laboratory experiment with flume....