Vertigenesis in soils of the central chernozemic region of Russia

On the basis of soil studies along routes and on key plots, 35 new areas of soils with definite features of vertigenesis have been identified in Belgorod and Voronezh oblasts and in the northern part of Volgograd oblast (in the Don River basin). Earlier, vertic soils were not noted for these areas. In the studied region, their portion in the soil cover is much less than 1%. All the delineated areas of vertic soils are confined to the outcrops of swelling clay materials of different origins (marine, lacustrine, glacial, and colluvial sediments) and ages (Quaternary or Tertiary) that may be found in four landscape positions: (1) in the deep closed depressions within vast flat watersheds; (2) in the bottoms of wide hollows on interfluvial slopes and, sometimes, on steeper slopes of local ravines; (3) in the hydromorphic solonetzic soil complexes, and (4) on step-like interfluvial surfaces with the outcrops of Tertiary clays. Within the studied areas, soils with different degrees of expression (six grades) of vertic properties are present. These soils belong to the type of dark vertic soils proper and to vertic subtypes of different soil types according to the Russian soil classification system; according to the WRB system, they belong to Vertisols proper and to reference soil units with a Vertic prefix in the groups of Chernozems, Phaeozems, and Solonetzes. Statistical data on the morphometric indices of the vertic properties (the depth and thickness of the soil horizons with slickensides, a wedge-shaped structure, and cracks filled with material from the upper horizons) and the depth and thickness of the Vertic horizon are analyzed.     

Ecological limits of gray forest soil erosion in central regions of the European part of Russia

This article describes a “humus“ linear modification of the Skidmore method, allowing us to calculate the tolerable limits of soil loss taking into account the current ecological requirements and economic opportunities. These limits were developed depending not only on the genetic types of soil, but also on the degree of its erodability, types of use, the structure of crop rotation, and crop capacity.     

允许土壤流失量与合理土壤流失量

 为确定防治农田土壤侵蚀的标准,20世纪中叶美国土壤学家首先提出了“允许土壤流失量”的概念,之后这一概念又延伸应用到流域和区域土壤侵蚀评价。“允许土壤流失量”的概念在全球,包括在中国得到了广泛的应用。随着土壤侵蚀及相关学科的发展,特别是全球变化研究的深入,可持续发展及健康河流理念的提出及水土保持实践中遇到的新挑战,“允许土壤流失量”的科学性和实用性方面存在的缺陷逐渐显现出来。本文在简要介绍“允许土壤流失量”由来的基础上,着重讨论“允许土壤流失量”存在的问题,并提出“合理土壤流失量”的概念及其确定的原则与方法。     

Evidence of plaggen soils in European North Russia (Arkhangelsk region)

To clarify whether a particular group of soils of Archangelsk region (European N Russia) with humus‐rich topsoils exceeding the plowing zone supports an anthropogenic formation, four exemplary profiles were investigated. The investigation sites are characterized by distinct elevated surfaces, and the soils show thick toplayers of up to 60 cm with enrichment of soil organic matter and artifacts like brick, charcoal, and peat fragments, all indicating an anthropogenic origin. Increased phytolith amounts and high P contents of up to 800 mg kg^–1 citric acid–soluble P and up to 1,400 mg kg^–1 total P in the top horizons support an anthropogenic influence. These properties are very similar to the Plagganthrepts of NW Europe. The same is true regarding the main management aims: increasing soil fertility and overcoming the need of bedding materials. Having the required depths of the anthropogenic topsoil, the properties of the soils of the Archangelsk region allow a classification as Agrozems (Russian classification), Plaggenesche (German classification), and Plagganthrepts (US taxonomy). Since the high base saturation of the topsoil excludes a designation as plaggic horizon, the topsoil has to be considered as terric horizon, which leads to a classification as Terric Anthrosol according to WRB.     

Assessment of background concentrations of heavy metals in soils of the northeastern part of European Russia

The assessment of background concentrations of heavy metals in soils of the southern regions of the Komi Republic has been performed. Within the accumulative landscapes, soils are enriched with virtually all the studied heavy metals in comparison with the eluvial landscapes. A database of the content of heavy metals has been developed using GIS technologies, and maps showing the distribution of heavy metals in soils of the southern part of the Komi Republic have been obtained.     

Genetic specificity and geography of taiga soils in the central part of the Baikal region

A specific feature of the development of automorphic taiga soils in the Baikal region is the lack of correspondence between the weak intensity of the soil chemical weathering and the high intensity of the removal of alkaline-earth elements from the soil profile in the form of suspensions. The loss of the clay fraction affects the water-physical properties of these soils and their temperature regime. The areas of different soil types in the northern and middle taiga zones have been calculated on the basis of soil maps of different scales. It is shown that podburs and acid soddy taiga soils predominate in these zones; the area of podzols, which were previously considered to be the dominant soil type in the middle and southern taiga zones, is smaller.     

Changes in the Rate of Soil Loss in River Basins within the Southern Part of European Russia

Eurasian Soil Science - Four river basins located in the forest, forest-steppe, and steppe zones of European Russia were evaluated for two time intervals (1960–1985 and 1986–2015) based...     

Soil loss tolerance values for different physiographic regions of Central India

In India, a single soil loss tolerance ( T ) value of 11.2 Mg/ha is by default used for formulating land restoration strategies for all soil types, climates and vegetation covers. However, this single 'T' value does not represent a true picture of soil loss tolerance under all land uses. The objective of our study was to develop adjusted ' T ' values for Central India using soil infiltration rate, bulk density, total organic carbon, erodibility and soil pH. Soil state was defined using a quantitative model involving different soil functions which were used to convert soil parameters to a 0 to 1 scale. The normalized values were then multiplied by appropriate weighing factors based on relative importance and sensitivity analysis of each indicator. Based on overall assessment, each soil mapping unit was categorized into soil groups I, II or III. A general guideline of USDA – Natural Resource Conservation Service (USDA-NRCS) was followed to calculate soil loss tolerance for each soil group using effective soil depth. Adjusted ' T ' values for Central India ranged from 2.5 to 12.5 Mg/ha compared with a default value of 11.2 Mg/ha. Use of these values for soil mapping units will improve conservation planning and assist with planning the development of sustainable agriculture.     

Soil and erosion features of the central plateau region of Tigrai,Ethiopia

The results of reconnaissance soil surveys covering 6,000 km² are used to describe the Central Plateau region, which lies at elevations of 2,000 to 2,800 m in northern Ethiopia. Landform and soil sequences on calcareous shales, dolerites and sandstones are described, in which the principal soil units are Lithosols, Luvisols, Cambisols, Arenosols and Vertisols. Detailed morphological and analytical data are presented for a profile representative of arable soils in each sequence.Small-scale subsistence cultivation of cereals is the dominant land use; all land which is physically cultivable is at present cultivated. Settlement patterns are closely related to soil type, nucleated settlement occurring on fine textured soils but dispersed settlement on coarser textured and more freely draining soils.Erosion and soil moisture features of the three landforms described were investigated and compared. Empirical methods and suspended sediment measurements indicate high rates of regional soil loss (17–33 t ha^?1 yr^?1), accounted for by seasonally high rates of rainfall erosivity, steep terrain and poor land use. The recent development of gully erosion is seen to be linked to the disintegration of waterfall tufas. Application of the universal soil loss equation to arable lands indicates potential annual soil losses in the range of 400 t ha^?1 on Vertisols to 200 t ha^?1 on Cambisols: differences in rates are ascribed principally to differences in crop planting dates, which affect the degree of vegetative protection during periods of high rainfall erosivity.Soil moisture is shown to be in the available range for less than three months in the year. The time at which moisture in the profile enters the available range differed between the three soils monitored and was found to be closely related to the crop planting date, thus indirectly affecting the erosion hazard.     

Fungi-to-bacteria ratio in soils of European Russia

The selective inhibition technique by specific antibiotics (streptomycin, cycloheximide) applied to substrate-induced respiration (SIR) measurement was used to test the relative contribution of fungi to bacteria (F/B ratio) to the overall microflora-induced activity in soils of European Russia. Investigated soils covered a wide climatic transect and different ecosystem types including managed vs. natural ecosystems. Before direct comparison among sites, the antibiotic inhibition technique was optimized for soil characteristics. Once the optimal concentration was set, the combined effect of the two antibiotics resulted in average 60% inhibition of SIR. The analyzed sites (in total 47) including various biomes (tundra, middle taiga, southern taiga, subtaiga, dark coniferous forests outside the boreal region, steppe, mountain forests and arable sites), were characterized by a wide range of soil pH_w (3.95–7.95), soil organic carbon (0.69–24.08%), soil microbial biomass carbon (149–5028 µg C g^?1 soil) and soil basal respiration (0.24–8.28 µg CO₂-C g^?1 soil h^?1). In all the analyzed sites, a predominance of fungal over bacteria activity was observed with F/B ratios always higher than one (4.9 on average). Natural sites were characterized by higher F/B ratios (on average 5.6) compared to agricultural ones (on average 3.5).     

Soil structure changes due to different land-use practices in the central Zagruos region,Iran

In this study, the effect of land-use treatments and the feasibility of fractal dimension to quantify soil aggregate stability were investigated in the central Zagrous, Iran. For this purpose, the non-linear fractal dimension (D_nl), linear fractal dimension (D_l) and the mean weight diameter (MWD) of aggregates were compared. Soil samples from three sites with four adjacent land-use types, namely: forest area (F), cultivated lands adjacent to forest (CAF), pasture (P) and cultivated lands adjacent to pasture (CAP) were collected. Results showed that soils under cultivated lands had higher bulk density (BD) (1.30–1.38 Mg m^?3) compared to the adjacent soils under forest (1.19 Mg m^?3) and pasture (1.21 Mg m^?3). In the 0–15 cm layer, soil organic matter (SOM) content in the cultivated plots were respectively 30% and 31% lower compared to the forest and pasture soils. The lowest CVs belonged to D_nl (5–8%) demonstrating that D_nl was more accurate than D_l (8–14%) and MWD (30–53%) methods. CAP had the largest value of D_nl, while P had the smallest value of D_nl. Difference of D_nl between forest and pasture was not significant, whereas both of them significantly differed from CAF and CAP. D_l did not differ significantly between forest and CAF. There were significant differences between forest and pasture for the measured MWD. Both fractal dimensions had negative correlation with MWD, SOM, hydraulic conductivity (HC) and macroaggregates (>0.25 mm) and positive correlation with BD and total porosity (TP).     

Dynamics of agricultural soil erosion in European Russia

Socioeconomic transformation together with climate change in recent decades significantly affected the geography of agricultural erosion in European Russia. Calculations of erosion rate and soil loss from slopes using logical-mathematical erosion models within different landscape zones and administrative regions revealed spatial-temporal regularities in the dynamics of these parameters and made it possible to assess the role of changes in the main natural and anthropogenic factors of erosion. A universal significant reduction in the mass of soil material washed from tilled slopes is revealed on the background of multidirectional changes in erosion rate.     

Bioproductivity of spruce stands in northern European Russia

The bioproductivity of forest ecosystems in terms of forest succession and biodiversity has been studied in northern European Russia near Arkhangelsk since the 1930s. The relationship between forest productivity and forest treatments (thinning and other silvicultural practices) is still not well understood. In this paper, results are reported for spruce-birch stands of natural origin that have undergone thinnings of various intensities over the past 30 years. Changes in stand aboveground and root biomass were recorded in a series of re-measurements and for a series of different thinning intensities and are reported here. A number of biotic and abiotic factors play important roles in determining the productivity and the distribution in biomass components. These factors are changed by thinning treatments. Thus the productivity and structure of foliage as well as other aboveground and belowground biomass components were found to be dependent on the density and spatial distribution of the trees in the stand; production of merchantable stem-wood was also influenced by thinning treatments. The optimum density needed for maximum stand production, however, need not always be best from the economic perspective.     

基于下游河流健康的黄土高原土壤容许流失量

 在总结分析前人有关黄河下游冲淤平衡时不同含沙量的临界流量和水体污染物质量浓度研究成果的基础上,利用花园口、高村水文站逐日水沙资料,推算不同水文年黄河下游水沙冲淤平衡时的临界输沙量为平水年6.54亿t、丰水年8.83亿t、枯水年3.95亿t,平均6.44亿t。以氨氮和全磷为指标,分析三门峡、花园口和高村断面因水土流失引起的非点源污染状况,参照地表水环境质量标准,得到黄河下游河道达到Ⅲ类和Ⅱ类水质标准的临界输沙量三门峡至高村河段平均为7.93亿和5.20亿t。同时,以黄河下游河道水沙平衡和满足某一水质标准为河流健康的约束条件,结合水利水土保持措施减沙量、头道拐水文站多年平均输沙量和黄土高原泥沙输移比的研究成果,推算黄河下游河道水沙平衡且分别达到Ⅲ类或Ⅱ类水质标准时,黄土高原土壤容许流失量相应为9.41亿和8.41亿t。研究结果可为黄土高原水土流失治理提供科学依据。     

Soil attribute database of Russia

Russia has long needed a world-level soil attribute (profile) information database which should become the basis for creating a system of monitoring of the state of soils and for developing measures for their conservation and efficient land use. A unified system of gathering and storing information on soils, which at the same time would be open for general use, is needed. The present work is devoted to problems of the concept and methodology of creating a soil geographic database (SGDB) of Russia. The structure and content of the soil attribute database, underlying which is the concept of representative soils profiles, are given. A list of classifiers for preparing data presentation formats in the SGDB on the basis of existing concepts of soil morphology and classifiers characterizing the main physicochemical properties of soils is developed. The work underlies the creation of an information resource—“Soil-Geographic Database of Russia. Project of the Dokuchaev Soil Science Society”—on the Internet at the address .     

松辽平原中部地区应对气候干旱变化的土壤耕作技术

近30a松辽平原中部地区气候变化显著,该地区玉米生产干旱风险增加。论文利用四平、长春等7个站点的逐日气候数据,分析了近30a松辽平原中部地区玉米季(5-9月)气候变化情况,研究发现该地区玉米季降雨量呈现减少趋势,平均温度、最高温度和最低温度均呈增加趋势;整体上玉米季干旱风险加剧,近10a发生频率为60%,增加幅度尤为明显。在此基础上,该文从土壤耕作技术应对角度分析了免耕(NT)、旋耕(RT)、翻耕(CT)和宽窄行(DL)等技术对土壤蓄水能力、透水性和紧实度的影响,探讨了不同耕作措施对土壤耕层结构的影响,比较了不同耕作技术下玉米产量差异,分析了土壤耕作措施对气候干旱变化的适应性。结果表明:以免耕和宽窄行技术为核心的保护性耕作技术是松辽平原中部地区应对干旱气候最为合理的土壤耕作技术,对于减小该地区玉米季干旱风险,提高玉米产量具有重要意义。     

Cartographic Assessment of Soil Diversity in Russia

The paper describes approaches assessing the diversity of soils in Russia, as well as algorithms for quantitatively assessing the differentiation of soil bodies and covers. To assess soil diversity (or the degree of differentiation of parent rock materials into soil bodies and soil covers), two indices have been introduced: the vertical differentiation index (Ird) and the spatial lateral differentiation index (Ild (red)). These indices were computed based on the soil cover structure shown on the Soil Map of the Russian Federation on a scale of 1: 2.5 M within the spatial framework of the Map of Soil-Ecological Zoning of the Russian Federation on a scale of 1: 2.5 M. Based on the data obtained, the most complex soil covers and soil profiles on plains were identified at the boundary of the Boreal and Subboreal geographical belts in the zones of soddy-podzolic soils (umbric albeluvisols/umbric podzols) of the southern taiga and gray forest soils (albic luvisols/luvic greyic phaeozems) of deciduous forests characterized by widespread occurrence of dynamically mature soils, as well as in mountainous soil provinces of the Altai and Caucasus.     

Biologically Active Organic Matter in Soils of European Russia

Experimental and literature data on the contents and stocks of active organic matter in 200 soil samples from the forest-tundra, southern-taiga, deciduous-forest, forest-steppe, dry-steppe, semidesert, and subtropical zones have been generalized. Natural lands, agrocenoses, treatments of long-term field experiments (bare fallow, unfertilized and fertilized crop rotations, perennial plantations), and different layers of soil profile are presented. Sphagnum peat and humus–peat soil in the tundra and forest-tundra zones are characterized by a very high content of active organic matter (300–600 mg C/100 g). Among the zonal soils, the content of active organic matter increases from the medium (75–150 mg C/100 g) to the high (150–300 mg C/100 g) level when going from soddy-podzolic soil to gray forest and dark-gray forest soils and then to leached chernozem. In the series from typical chernozem to ordinary and southern chernozem and chestnut and brown semidesert soils, a decrease in the content of active organic matter to the low (35–75 mg C/100 g) and very low (<35 mg C/100 g) levels is observed. Acid brown forest soil in the subtropical zone is characterized by a medium supply with active organic matter. Most arable soils are mainly characterized by low or very low contents of active organic matter. In the upper layers of soils, active organic matter makes up 1.2–11.1% of total C_org. The profile distribution of active organic matter in the studied soils coincides with that of C_org: their contents appreciably decrease with depth, except for brown semidesert soil. The stocks of active organic matter vary from 0.4 to 5.4 t/ha in the layer of 0–20 cm and from 1.0 to 12.4/ha in the layer of 0–50 cm of different soil types.     

Laboratory incubation studies of chlorophenoxyacetic acids in chernozemic soils

The relative persistence of 2,4-D, MCPA and 2,4,5-T in some Saskatchewan soils was assessed under laboratory conditions. Under moist conditions, 2,4-D and MCPA showed half-life times of between 14 and 41 days but the MCPA half-life was usually 1 or 2 days longer. 2,4,5-T exhibited a half-life period over twice the length of the other chemicals. The half-life times were directly correlated to microbial plate counts, the larger numbers of soil microorganisms being associated with shorter residence times. Half-lives depended on soil moisture content and the best moisture levels for chemical loss appeared to be just less than field capacity. The use of ¹⁴C in 2,4-D incubation studies showed that the initial cleavage of the 2,4-D molecule was associated with the ether linkage and was not a decarboxylation.