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.     

Correction of a large-scale soil map with the use of the new classification system of Russian soils

A large-scale soil map of one of the farms in the south of Karelia has been analyzed. This map was initially compiled in 1979 on the basis of the official Classification and Diagnostics of Soils of the Soviet Union (1977). We have corrected it with the use of the new Classification and Diagnostics of Russian Soils. Both the names of the map units and the particular delineations on the map have been changed. These changes are related to differences in the principles of soil diagnostics in the old and new classification systems and to real changes in the soil cover that have taken place after the map’s compilation. In particular, large areas of peat bogs have been drained, and the cultivated peat soils have been subjected to accelerated mineralization. Surface planing works after digging drainage channels have also changed the soil cover pattern. The revised large-scale soil map developed on the basis of the new classification system gives more adequate information about the real soil cover.     

Modern Azerbaijani soil classification system

A new soil classification system is elaborated on the basis of the legend to the soil map of Azerbaijan on a scale of 1: 100 000. The classification system includes above-type categories and a detailed list of anthropogenically transformed soils. It is based on the profile-genetic and evolutionary concepts. The soil classes (the highest taxon) include naturally developed, anthropogenically modified, and technogenically disturbed soils. The lists of soils of the first two classes are similar to those of the new Russian soil classification system, contrary to the class of technogenically disturbed soils, which is subdivided into soil orders with respect to the particular kinds of soil disturbance. The concept of soil types is generally preserved in the new classification. The diagnostics of soil types are based on the sequences of genetic horizons (types of soil profiles). The latter are used for finding proper correlation of the distinguished soil types with analogous soils in the WRB system.     

Orders in the soil classification system of Russia: Taxonomic distance as a measure of their adequate identification

Taxonomic distances between pairs of soil orders in the Russian soil classification system have been calculated using a methodology suggested for calculation of taxonomic distances between the Reference Soil Groups in the international soil classification system (WRB). Basing on the data obtained, some proposals for the development of the Russian soil classification system have been formulated. Most of the orders are characterized by considerable taxonomic distances between them, and their identification in the classification system is doubtless. Small taxonomic distances are characteristic of the following pairs of orders: organo-accumulative and structural-metamorphic soils, hydrometamorphic soils and lithozems, and cryometamorphic and eluvial soils. Therefore, criteria for defining some orders, and/or profile formulas for some soil types composing the orders may be revised. The comparison of taxonomic distances between soil orders in the Russian system and between Reference Soil Groups in the international system allows us to suggest their certain similarity.     

Diagnostic horizons in the Russian soil classification system

The analysis of the responses of users of the substantive-genetic Russian soil classification system revealed some problems concerning the genetic (diagnostic) horizons. Applying horizons is essential since soil diagnostics are based on their identification and their combinations in soil profiles. In the recent Russian system, there are many diagnostic horizons, and their recognition is not always easy. This review is aimed at displaying the main elements and the genetic essence of the horizons, as well as the reasons to choose the diagnostic criteria and parameters for most of them. The horizons are grouped into genetic sets, and the specific properties of the horizons are emphasized, as well as the differences between the horizons and the feasibility to introduce new horizons. A rough comparison of the diagnostic horizons in the Russian and WRB systems revealed the considerable similarity of the taxa, whose definitions depend on the presence of the diagnostic horizons: these are the orders and soil reference groups, respectively.     

Inclusion of soils and soil-like bodies of urban territories into the Russian soil classification system

The results of the Internet discussion on the classification of urban soils aimed at evaluating their possible inclusion into the modern Russian soil classification system adopted by a wide range of specialists are presented. The first step was to address the urban diagnostic horizons as the basis for identifying soil types according to the rules of the Russian soil classification. New diagnostic horizons were proposed for urban soils: urbic (UR), filled compost-mineral (RAT), and filled peat (RT). The combination of these horizons with other diagnostic horizons and layers of technogenic materials correspond to different soil types. At the subtype level, the diagnostic properties (qualifiers) that may reflect both natural phenomena (gley, alkalinity) and technogenic impacts on the soils (urbistratified; phosphatic; or poorly expressed urban—ur, rat, rt) are used. Some corrections were proposed for the system of parent materials in urban environments. Urban soils formerly described in another nomenclature—urbanozems, urbiquasizems, and culturozems—are correlated with the taxa in all the trunks of the system. The proposals accepted can be used for the next updated version of the new Russian soil classification system.     

Historical aspects of soil classification in Japan

Historical perspective of soil classification in Japan from Max Fesca's soil classification in 1882 to the “Unified Soil Classification System of Japan (2002)” was outlined, aiming at reviewing the progress in soil classification. The evolution can be divided into the following five aspects: 1) Max Fesca's soil texture survey and soil classification from the agro-geological point of view under the influence of the German school; 2) Introduction of the concept of pedology into the classification under the influence of the Russian school led by Dokchaev; 3) Brief history of the classification of Andosols which has exerted a considerable influence on soil classification worldwide; 4) Soil classifications developed through the implementation of national soil survey projects to independently evaluate land suitability for the cultivation of paddy rice, upland crops, and for forest establishment; 5) Attempts to develop a comprehensive soil classification system in order to unify soil classification systems for the above-mentioned land uses from 1963 to the present.     

The works of N.N. Rozov in the field of the geography and ecology of world soils

The contribution of N.N. Rozov to the development of our knowledge about the geography and ecology of soils of the Soviet Union and the world is discussed. It is shown how the scientific discussions with participation of Rozov were gradually transformed into the contents of the Soil Map of the World (1975), and how the soil-bioclimatic approach toward mapping developed by Rozov was combined with the geochemical approach and realized in the map. A poorly known work on the soil-ecological regionalization of the world performed by Rozov and published in the Resources and Environment World Atlas in 1998 (12 years after Rozov’s death) is analyzed. Up to now, this work remains an unsurpassed compendium of data on soil regimes.     

Classiology and soil classification

Classiology can be defined as a science studying the principles and rules of classification of objects of any nature. The development of the theory of classification and the particular methods for classifying objects are the main challenges of classiology; to a certain extent, they are close to the challenges of pattern recognition. The methodology of classiology integrates a wide range of methods and approaches: from expert judgment to formal logic, multivariate statistics, and informatics. Soil classification assumes generalization of available data and practical experience, formalization of our notions about soils, and their representation in the form of an information system. As an information system, soil classification is designed to predict the maximum number of a soil’s properties from the position of this soil in the classification space. The existing soil classification systems do not completely satisfy the principles of classiology. The violation of logical basis, poor structuring, low integrity, and inadequate level of formalization make these systems verbal schemes rather than classification systems sensu stricto. The concept of classification as listing (enumeration) of objects makes it possible to introduce the notion of the information base of classification. For soil objects, this is the database of soil indices (properties) that might be applied for generating target-oriented soil classification system. Mathematical methods enlarge the prognostic capacity of classification systems; they can be applied to assess the quality of these systems and to recognize new soil objects to be included in the existing systems. The application of particular principles and rules of classiology for soil classification purposes is discussed in this paper.     

Methodological aspects of soil monitoring on the plains of Dagestan

Methodological aspects of soil monitoring works performed on the plains of Dagestan are discussed. The information system for soil monitoring includes data on the centennial natural and anthropogenic dynamics of the environment, the soil properties, and the soil cover patterns; it also includes long-term forecasts of soil degradation processes and their indicators to be controlled and monitored. Recent changes in the soil cover on the plains of Dagestan have been assessed with the use of new technologies and criteria.     

Comparison of the results of soil profiles’ diagnostics performed in three classification systems

Three soil classification systems—the World Reference Base for Soil Resources (WRB), Soil Taxonomy, and the recent Russian system—were used for the identification of 17 soil profiles in southwestern Poland; all the systems put emphasis on the soil properties as diagnostic criteria. Different soils developed on glaciofluvial plains, loessic uplands, and in the Sudetes Mountains were classified. The best correlation between the classification decisions in the different systems was obtained for the most widespread soils owing to the similarity of the diagnostic criteria, which were essentially close although not coinciding. The most prominent divergence between the systems in both the names and the taxonomic categories of the soils was found for the polygenetic soils and for the soils developing from the lithologically discontinuous parent materials. It was also found that the diagnostic elements differ in terms of their taxonomic importance among the classification systems.     

Global patterns of soil phosphatase responses to nitrogen and phosphorus fertilization

Hydrolysis of organic phosphorus(P) by soil phosphatases is an important process of P cycling in terrestrial ecosystems, significantly affected by nitrogen(N) and/or P fertilization. However, how soil acid phosphatase(ACP) and alkaline phosphatase(ALP) activities respond to N and/or P fertilization and how these responses vary with climatic regions, ecosystem types, and fertilization management remain unclear. This knowledge gap hinders our ability to assess P cycling and availability from a glo...     

Small-scale soil maps and the scientific heritage of N.N. Rozov

The comparative analysis of small-scale maps of the USSR has revealed the characteristics of their contents, concepts, and ways of compilation and cartographic representation. The facies-zonal concept is reflected both in the map legends and the patterns of the mapping units. The differences between the maps reflect the time of their creation: the degree of knowledge on the soils, the contribution of the geographic forecast, and the objective of the maps and their scale. Especial importance in soil cartography and geographic education belongs to the map of 1954 compiled by Rozov. Forty years later, it was replaced by a map of similar purpose, scale, and mapped area. This map was compiled at the Faculty of Geography (Moscow State University), and it has inherited many features of its predecessor—the map of Rozov.     

冻融过程中土壤颗粒组成的重建：研究综述

Studies conducted over several decades have shown that the freeze-thaw cycles are a process of energy input and output in soil, which help drive the formation of soil structure, through water expansion by crystallization and the movement of water and salts by thermal gradients. However, most of these studies are published in Russian or Chinese and are less accessible to international researchers. This review brought together a wide range of studies on the effects of freezing and thawing on soil structure. The following findings are summarized: i) soil structure after freeze-thaw cycles changes considerably and the changes are due to the mechanical fragmentation of soil coarse mineral particles and the aggregation of soil fine particles; ii) the particle size of soil becomes homogeneous and the variation in soil structure weakens as the number of freeze-thaw cycles increases; iii) in the freezing process of soil, an important principle in the variation of soil particle bonding is presented as: condensation → aggregation → crystallization; iv) the freeze-thaw cycling process has a strong effect on soil structure by changing the granulometric composition of mineral particles and structures within the soil. The freeze-thaw cycling process strengthens particle bonding, which causes an overall increase in aggregate stability of soil, showing a process from destruction to reconstruction.     

Relationships between soil aggregation and mycorrhizae as influenced by soil biota and nitrogen nutrition

 The effect of the form of N nutrition on soil stability is an important consideration for the management of sustainable agricultural systems. We grew soybean [Glycine max (L.) Merr.] plants in pot cultures in unsterilized soil, and treated them by (1) inoculating them with Bradyrhizobium japonicum, fertilizing with (2) nitrate or (3) ammonia, or (4) by providing only minimum N amendment for the controls. The soils were sampled at 3-week intervals to determine changes in water-stable soil aggregates (WSA), soil pH, the development of roots, arbuscular mycorrhizal (AM) soil and root colonization, and selected functional groups of soil bacteria. The soil fauna was assayed at the end of the experiment (9 weeks). WSA was correlated positively with root and AM soil mycelium development, but negatively with total bacterial counts. Soil arthropod (Collembola) numbers were negatively correlated with AM hyphal length. Soils of nodulated and ammonia-fertilized plants had the highest levels of WSA and the lowest pH at week 9. Sparse root development in the soils of the N-deficient, control plants indicated that WSA formation was primarily influenced by AM hyphae. The ratio of bacterial counts in the water-stable versus water-unstable soil fractions increased for the first 6 weeks and then declined, while counts of anaerobic bacteria increased with increasing WSA. The numbers of soil invertebrates (nematodes) and protozoans did not correlate with bacterial counts or AM soil-hyphal lengths. Soil pH did not affect mycorrhiza development, but actinomycete counts declined with decreasing soil pH. AM fungi and roots interacted as the factors that affect soil aggregation, regardless of N nutrition. Received: 20 December 1997     

Legal aspects of soil conservation and land cadaster works

The analysis of modern Russian legislation in the sphere of environmental protection, management of natural resources, soil conservation, and land cadaster works has been performed. It is shown that a common federal approach to environmental impact assessments and soil quality assessments is virtually absent. Ecological indices are not taken into account in the federal land cadaster. Most of the recently adopted legislative regulations in this sphere have a technocratic character. The recent governmental regulations on land and environmental monitoring have still not been put into practice. To ensure soil conservation policy and protect soils as a component of the environment, a distinction should be made between the notions of soil and land in the legal documents. The basic principles of the proposed law “On Soil Conservation” are outlined. It is argued that a system of soil-ecological criteria should be elaborated for the proper assessment of soil quality. As a soil conservation service is absent in Russia, it is suggested that the Dokuchaev Soil Science Society should organize an association for the protection and rehabilitation of Russian soils.     

The particle-size distribution in soils: Problems of the methods of study,interpretation of the results,and classification

The analysis of literature sources and a database on soil physical properties collected by the Department of Soil Physics and Amelioration of Soils of the Faculty of Soil Science of Moscow State University made it possible to compare three major constituents of the particle-size distribution analysis (PSDA): (a) the classification of soil separates with respect to their sizes and the classification of soil textures, (b) the procedures used to prepare soil samples for the PSDA, and (c) the specificity of the determination of the particle-size distribution by different methods. It was shown that there are good physical and statistical grounds for the conversion of data on the particle-size distribution from the Russian classification system into other systems. Much larger problems are related to the pretreatment of soil samples for the PSDA. The diversity of existing methods, classification schemes, and technical devices based on different physical principles (sedimentation and laser diffractometry) should be taken into account in the analysis and quantitative conversion of particle-size distribution data from a given classification system into another system. The Russian classification of soil textures and soil particle-size groups developed by N.A. Kachinskii has certain advantages and can be easily converted into other systems. In the choice of a particular system, it is important to take into account the goals of the study. Agreement between soil scientists concerning the major constituents of the PSDA has to be reached.     

Long-term soil feedback on plant N allocation in defoliated grassland miniecosystems

Defoliation of plants is known to have effects on soil organisms and nutrient availability in grassland communities, but few studies have examined whether changes in soil attributes can further feed back to plant growth and plant nutrient content. To examine defoliation-induced soil feedbacks, we established replicated miniecosystems with a grass Phleum pratense, defoliated half of the systems, collected soil from both defoliated and non-defoliated systems and planted new seedlings into each soil. The two soils did not differ in promoting shoot and root growth. However, seedlings that grew in the soil collected from defoliated systems had higher shoot N content, allocated relatively more N to shoots and had lower root N concentration than those growing in the soil collected from non-defoliated systems. Our study provides novel evidence that defoliation can generate long-lasting changes in grassland soil that in turn can affect plant N allocation.     

Analysis of soil-climatic relationships on the basis of the soil map and the BIOME database

The analysis of soil-climatic relationships was performed on the basis of the BIOME database on climate and vegetation created by the V.N. Sukachev Institute of Forestry (Siberian Branch of the Russian Academy of Sciences) and the Soil Map of the Russian Federation (1: 2.5 M scale) for the southern part of the boreal zone of Siberia. Climatic parameters (accumulated daily temperatures above 10°C, continentality of the climate, and humidity of the climate) specifying the development of major types of mesomorphic soils on this territory were determined. The climatic contacts between different soil groups were established. The soil diversity in climatic ecotones was characterized. The criteria of steady and unsteady position of soils in the space of climatic coordinates were analyzed, and the measure of the climatic sensitivity of soils was suggested.     

Microbial and soil parameters in relation to N mineralization in soils of diverse genesis under differing management systems

 Oregon soils from various management and genetic histories were used in a greenhouse study to determine the relationships between soil chemical and biological parameters and the uptake of soil mineralized nitrogen (N) by ryegrass (Lolium perenne L.). The soils were tested for asparaginase, amidase, urease, β-glucosidase, and dipeptidase activities and fluorescein diacetate hydrolysis. Microbial biomass carbon (C) and N as well as metabolic diversity using Biolog GN plates were measured, as were total soil N and C, pH, and absorbance of soil extracts at 270 nm and 210 nm. Potentially mineralizable N (N₀) and the mineralization rate constant (k) were calculated using a first order nonlinear regression model and these coefficients were used to calculate the initial potential rate of N mineralization (N₀ k). Except for Biolog GN plates, the other parameters were highly correlated to mineralized N uptake and each other. A model using total soil N and β-glucosidase as parameters provided the best predictor of mineralized N uptake by ryegrass (R ² =0.83). Chemical and biological parameters of soils with the same history of formation but under different management systems differed significantly from each other in most cases. The calculated values of the initial potential rate of mineralization in some cases revealed management differences within the same soil types. The results showed that management of soils is readily reflected in certain soil chemical and biological indicators and that some biological tests may be useful in predicting N mineralization in soils. Received: 31 January 1997