Soils and the soil cover of mountainous tundra and forest landscapes in the Central Khangai of Mongolia

Specific features of the soil formation and soil cover patterns in the mountainous alpine tundra and forest landscapes of the Central Khangai Range are analyzed. It is shown that the specific mucky grayhumus permafrost-affected soils are only formed under larch forests within the tundra-alpine and forest zones. Other soils have a wider geographic area. The morphological, physicochemical, and chemical characteristics of the widespread soils are given. A medium-scale map of the soil cover patterns—soil complexes, combinations, and mosaics—has been developed for the studied area.     

Soils on overburden dumps in the forest-steppe and mountain taiga zones of the Kuzbass

The properties of the soils forming on coal dumps significantly depend on the properties of the parent rocks and the technology of creating the dumps. In the forest-steppe and mountain taiga zones of the Kuznetsk Coal Basin, argillites, siltstones, and sandstones are the overburden and enclosing rocks. They are responsible for the alkaline reaction and the same microelement composition in almost all the soils studied. The nonselective formation of the dumps and the predominance of the coarse fraction in the rocks composing the dumps is a cause of the wide distribution of petrozems and humus petrozems on their surface. The presence of a great amount of coal particles in the substrates and the incorrect planning of the dumps may be the reasons for their self-ignition, which can change the composition of polycyclic aromatic hydrocarbons in the soils of the dumps.     

Soils of floodplains in arid regions of Inner Asia (the Zavkhan River,Mongolia)

The environmental conditions of soil formation and the diversity and classification position of soils developing on the Zavkhan River floodplain are considered, and the morphogenetic and agrochemical properties of these soils are characterized. It is shown that the conditions of soil formation on the floodplain of the Zavkhan River are specified by the mountainous topography, the effect of the large Mongol Els sand massif, the character of the alluviation processes, the groundwater level and salinity, and the regime of floods. The position of the floodplain in the system of altitudinal zones largely dictates the character of the soil cover pattern. In terms of the new Russian soil classification system, the soils studied belong to three trunks, four orders, and seven types: stratified humus alluvial soils, light-humus alluvial soils, light-humus quasigley alluvial soils, light-humus stratozems, and solonchaks. The soils of floodplain ecosystems in arid regions are characterized by low fertility. For their efficient use for pasturing and crop growing, the ecologically balanced differentiated application of manure, mineral fertilizers (NPK), and some microelements is required.     

Agrogenic evolution of automorphic chernozems in the forest-steppe zone (Belgorod oblast)

Agrochronosequences of chernozems with different periods of their use in rainfed farming with application of traditional technologies have been studied in a typical forest-steppe area in Belgorod oblast. Certain stages in the development of these soils during more than two centuries of their agricultural use have been identified. These stages are related to changes in the intensity and direction of soil forming processes, such as soil compaction, soil aggregation, dehumification of the upper horizons, calcification of the soil profiles, argillization, etc. A significant impact on the soil changes during the agrogenic evolution of chernozems is exerted by the digging activity of burrowers, which is especially pronounced in the old-arable chernozems.     

西南丘陵山区土地整理方案比选研究

新增耕地潜力是土地整理项目立项决策的重要依据，而新增耕地率是新增耕地潜力的反映，直接影响项目工程布局、投资预算以及效益问题。该文以重庆市忠县拔山土地整理项目为例，依据国土资源部不同土地开发整理项目新增耕地的两种最低门槛值10%和3%，进行土地整理方案比选设计，计算得到两种土地整理方案的新增耕地率分别为10.3%和4.02%，并从经济、生态和社会3方面，分别采用动态投资评估法、可拓物元分析法、综合指数法对两方案进行比选分析。结果表明：旱地坡改梯工程布局是造成两种土地整理方案新增耕地面积差异的主要原因；农田水利、道路工程以及防护林工程布局差异不大，只存在布局力度上的差异；从方案的系统效益看，新增耕地率10.3%的方案无论是动态投资回收年、生态环境关联度、社会效益指数，还是系统效益指数均优于新增耕地率为4.02%的方案；通过典型田块采用加权算法计算净耕地系数，可以作为西南丘陵山区土地整理项目净耕地系数的计算方法，但该方法中修正系数确定需要经过实地勘测和类比，这样可避免典型田块选择的主观性。     

Anthropogenic evolution of dark gray forest-steppe soils in the southern part of the Central Russian Upland

A sequence of dark gray forest soils developing under a virgin broadleaved forest and under croplands used for 100 and 150 years was studied in the southern part of the forest-steppe zone on the Central Russian Upland. The application of multiple study methods for these objects made it possible to trace the evolutionary changes in the soil properties during the 150-year-long period of regular plowing. Several important trends in the soil development under the impact of the cultivation were revealed: (a) an increase in the thickness of the humus layer (according to the measurements at 20 points for each of the objects), (b) an increase in the amount of mole tunnels, (c) a decrease in the coefficient of the textural differentiation of the soil profile (with respect to the clay content), (d) an increase in the contents and reserves of the major nutrients upon a stable pool of humus in the upper meter, and (e) some alkalization and carbonization of the profile. Powdery accumulations of carbonates and whitish calcareous coatings on the faces of prismatic peds appeared at a depth of more than 130 cm. The plowed soils contained thin deep fissures, the surface of which was covered by dark-colored clayey-humus coatings at the depth of 50–110 cm. The radiocarbon age of the humus in these coatings was 500–1000 years younger than the age of the humus in the soil mass between the fissures. This set of features attests to the evolution of the plowed dark gray forest soils into chernozems under the impact of plowing.     

A Comparative Analysis of the Microfabrics of Surface Horizons and Desert Varnish in Extremely Arid Soils of the Mojave (USA) and Trans-Altai Gobi (Mongolia) Deserts

The mineralogical composition of coarse fraction and characteristic features of the micro- and submicrofabrics and chemical composition of desert varnish on gravels of desert pavements and the underlying vesicular crust soil horizons were studied in the extremely arid soils of the Mojave (USA) and Trans-Altai Gobi (Mongolia) deserts. A set of common diagnostic features of elementary pedogenetic processes was identified in the automorphic desert soils developed on ancient (70–90 ka) piedmont plains composed of alluvial deposits with the high content of red-earth clay. The results of this study attest to the long and complicated history of the extremely arid soils with alternation of the humid and arid phases of pedogenesis reflected in a specific combination of textural (clay-illuvial) and carbonate pedofeatures and in the distribution patterns of iron, manganese, titanium, and barium in different layers of the desert varnish. The chemical composition of the latter did not depend on the mineralogical composition of the underlying substrates and was formed with active participation of soil microorganisms. This allowed us to conclude about the polygenetic (accretionary–microbiological) nature of desert varnish.     

Soils of the subtaiga landscapes on the northern spurs of the Tsagan-Daban Ridge in the Selenga Mountains

The soil cover patterns in the subtaiga landscapes on the northern spurs of the Tsagan-Daban Ridge in the Selenga Mountains have been studied. Gray-humus lithozems and bedrock outcrops are typical of the steep south-facing slopes under herbaceous pine forests. Soddy iron-illuvial podburs are formed under forest vegetation on gentle slopes of northern and western aspects with a thick mantle of loose colluvial deposits. Dark-humus metamorphic soils occur on the slopes of western and northwestern aspects below 700 m a.s.l. under secondary forb-grassy communities that replaced the initial herbaceous pine forests. Windblown hollows (yardangs) are occupied by humus psammozems under steppe pine forests. The morphological and physicochemical characteristics of these soils are discussed in the paper.     

Soils in the zone affected by mineral water springs at the foothills of the Eastern Sayan Ridge

Data on soils in the zone affected by mineral water springs at the foothills of the Eastern Sayan Ridge are analyzed. Changes in the soil properties take place with the increase in the distance from the sites of the water discharge: primitive petrozems (Lithosols) are replaced by calcareous petrozems and, then, by burozems (brown taiga soils, Cambisols). In dependence on the degree of the water mineralization, the salt content in the soils varies from 0.05 to 0.26%. The readily soluble salts include calcium, magnesium, and sodium chlorides; sulfates; and bicarbonates. The soil reaction varies from acid to alkaline, and the organic matter content varies from 0.5 to 15.0%.     

Soils of the Pavlovsk Park (Saint Petersburg)

Eurasian Soil Science - Soils of the Pavlovsk Park–the largest landscape park in Europe—have been studied, and large-scale mapping of the soil cover of the main areas of the park has...     

Soils of the Summer Garden (Saint Petersburg)

Soils of the Summer Garden—the first regular (French-style) garden in Russia—are characterized on the basis of the materials of field study performed during reconstruction of the garden in 2005–2011. Most of these soils are filled soils—urbostratozems—underlain by the loamy sands deposited in the Littorina Sea or by the buried gray-humus gleyic and gleyed soils. Urbostratozems are characterized by the slightly acid reaction in the topsoil horizons and slightly alkaline reaction in the middle-profile and lower horizons. The humus content in them varies from 0.2 to 6.8%; in the buried gray-humus soils, it is within 1.3–2.6%. The soils of the garden are characterized by the high and extremely high content of available phosphorus and the predominantly low content of available potassium as determined by Machigin’s method. The bulk content of Pb in the surface soil horizons during the period of our study exceeded the maximum permissible concentration by 3–20 times; the bulk contents of Cu and Zn exceeded the tentative permissible concentrations for coarse-textured soils by 2–6 and 4–20 times, respectively. The main sources of the soil contamination by the heavy metals are the nearby highways. Local contaminated area was also found near the household yard.     

西南山区林地空间格局和微地形对坡面地表产流的影响

为明确柏木空间格局和微地形对坡面地表产流的影响,该研究测定了西南山区10个径流小区的柏木空间格局及微地形特征,并观测其降雨和坡面产流过程,利用响应面分析法解析柏木空间格局和微地形对产流特征的影响.结果表明:1)中长历时大雨和中长历时暴雨条件下,地形起伏度、地表粗糙度、径流路径密度、柏木角尺度及柏木密度5个因子均与洪峰流...     

Soils of Altitudinal Zones of the Suntar-Khayata Ridge: Morphology,Properties, and Classification

Eurasian Soil Science - For the first time, a detailed diagnostics and classification of soils of the Suntar-Khayata Range have been performed. This study is a continuation of long-term soil...     

Ecological-geochemical state of soils in Ulaanbaatar (Mongolia)

Based on the results of the soil-geochemical survey, the assessment of the soil cover pollution in different Ulaanbaatar functional zones is given. The soils of the industrial and traffic zones concentrating a wide spectrum of pollutants (Zn, Mo, Cr, Cr, Cd, Pb, and Cu) are characterized by the strongest technogenic transformation. The soils of the residential areas accumulate Pb and Zn, while those of the recreation zone, Mo, Ni, and Cr. The geochemical mapping allowed distinguishing four groups of elements with similar distribution patterns determined by the common pollution sources, the specific features of the parent rocks, and the intensity of the migration. Among the natural and technogenic factors responsible for the accumulation of microelements in soils, the basic ones are the soil physical and chemical properties: the contents of organic matter (for As, Cd, Cu, Mo, Zn), physical clay (Ni, Co), sulfates (Pb, Sr), and the pH (Cr). The character of the land use noticeably affects the concentration of many elements. The soils of the city are assessed as weakly polluted (Zc = 11). The contents of As, Zn, Mo, and Pb exceeded their MPC in 100, 34, 20, and 16% of the city’s territory, respectively. As compared to the state of the soil cover in 1990, no significant changes were revealed.     

Agrogenic degradation of soils in Krasnoyarsk forest-steppe

Agrogenic degradation of soils in Krasnoyarsk forest-steppe was investigated. Paleocryogenic microtopography of microlows and microhighs in this area predetermined the formation of paragenetic soil series and variegated soil cover. Specific paleogeographic conditions, thin humus horizons and soil profiles, and long-term agricultural use of the land resulted in the formation of soils unstable to degradation processes and subjected to active wind and water erosion. Intensive mechanical soil disturbances during tillage and long-term incorporation of the underlying Late Pleistocene (Sartan) calcareous silty and clay loams into the upper soil horizons during tillage adversely affected the soil properties. We determined the contents of total and labile humus and easily decomposable organic matter and evaluated the degree of soil exhaustion. It was concluded that in the case of ignorance of the norms of land use and soil conservation practices, intense soil degradation would continue leading to complete destruction of the soil cover within large areas.     

Formation of Methyl Mercaptan in Paddy Soils (II)

In the previous paper₁₎, the authors proposed a method for determining methyl mercaptan formed in paddy soils. In this method, methyl mercaptan was expelled by nitrogen gas from Paddy soils, and was introduced into 4% mercuric CYanide solution after separation from hydrogen sulfide by hydrous calcium chloride and lead acetate (solid). The methyl mercaptan caught by mercuric cyanide solution was measured by colorimetric method using dimethyl-p-phenylenediamine and ferric chloride solutions. And then, the analysis of several field soils was conducted by using this method.     

垄作方向对不同坡位红壤坡耕地耕层土壤水分特征曲线的影响

  目的  探讨横坡垄作和顺坡垄作对不同坡位耕层土壤水分特征曲线的影响,为红壤坡耕地垄作方向的选择提供依据。  方法  采用压力膜仪法测定两种垄作方向、不同坡位（上部、中部、下部）耕层土壤水分特征曲线,并以Van Genuchten（VG）模型拟合该曲线,通过VG模型参数分析比较横坡耕作和顺坡垄作耕作后不同坡位土壤持水特点及其影响因素。  结果  红壤坡耕地耕层不同坡位土壤与0 ~ 1000 kPa水吸力对应的体积含水率为 0.36 ~ 0.66 cm3 cm?3,VG模型能够较好地表达两者间数量关系。顺坡垄作上部、中部和下部坡位耕层土壤VG模型参数饱和含水率θs分别为0.59、0.59和0.65 cm3 cm?3,残余含水率θr为0.37、0.38和0.41 cm3 cm?3且随着坡位降低而增大;横坡垄作上部、中部和下部坡位耕层土壤VG模型参数饱和含水率θs分别为0.58、0.56和0.59 cm3 cm?3,残余含水率θr为0.37、0.35和0.38 cm3 cm?3且随坡位降低呈先减小、再增加趋势变化。VG模型参数d、n均为0.11和0.92,随耕作方向、坡位变化不明显。  结论  总孔隙度和砂粒含量为影响不同垄作方向红壤耕层理化性质的主导因素。顺坡垄作上部和中部坡位耕层土壤持水能力不及下部坡位土壤,但就同一坡位比较,横坡耕层土壤的释水能力优于顺坡耕作,说明横坡耕作可改善土壤供水能力。     

Soils and land use in the Tigray highlands (Northern Ethiopia)

Land use in a 208 ha representative catchment in the Tigray Highlands, Dogu'a Tembien district in Northern Ethiopia was studied in relation to soil geography. Typical soils are Vertisols, Vertic Cambisols, Cumulic Regosols, Calcaric Regosols and Phaeozems. Patterns of land use vary greatly within the catchment and results from χ²‐tests showed strong associations (p < 0·001) between soil type and land use and crop production system. There is a strong association between cropland and colluvium high in basaltic content because the most fertile soils, such as Vertisols and Vertic Cambisols, have developed on this material. Preference is for autochthonous soils on in situ parent material, irrespective of the rock type, to be put under rangeland. Land use by smallholders in Dogu'a Tembien appears to be the result primarily of the interaction between environmental and social factors. Copyright © 2007 John Wiley & Sons, Ltd.     

Remediation of Pb-Contaminated Soils in the Guadiamar River Basin (SW Spain)

Soil remediation has been studied after a spill from a settling pond of a pyrite mine in Aznalcóllar (SW Spain). The affected area was approximately 55 km² and extended about 40 km from the spill. The Pb concentration in soils ranged from 35.8 to 3231.0 mg kg^-1, with a mean value of 385.8 mg kg^-1. The remediation techniques investigated included: manual and mechanical removal of the contaminated soil, mixing the upper part of the soils by ploughing, and addition of different amendment materials to reduce the Pb solubility, such as carbonates, zeolites, iron-rich soils, bentonites and yeasts. A combination of liming with iron-rich soils proved the most effective treatment.