Specific features of the morphology of volcanic soils in the altitudinal zones of Kamchatka

Under conditions of active volcanism, the soils on different geomorphic positions (from high-mountain landscapes to river valleys) are formed under the impact of periodic ashfalls. The exogenous processes affect the redistribution of volcanic ashes by the elements of the relief, so that the soils of different altitudinal zones have their own morphological specificity. It is suggested that two additional types of volcanic soils should be included in the new Russian soil classification: the type of alluvial volcanic soils in the order of volcanic soils and the type of volcanic lithozems in the order of lithozems. These soils can be considered intergrades between volcanic and alluvial soils and between volcanic soils and lithozems, respectively.     

Fertility of soils under spruce forests of the Khibiny Mountains

The development of fertility of soils on different parent rocks is considered for different types of spruce forests in the Khibiny Mountains. The spruce forests of Mts. Kuel??por, Vud??yavrchorr, Chil??mana, and Saami were the objects for the study. The results showed that the fertility level of the soils of the Khibiny Mountains was determined by the combined influence of the parent rock??s composition and the vegetation. The differences in the soil properties are mainly explained by the composition of the parent rocks. The pod-burs differ from the podzols by the higher contents of organic matter, nitrogen, and available nutrients. The podzols are the most acid soils there. The podburs of Mt Kuel??por developing on base-rich parent rocks are the most fertile. The differences in the fertility of the soils on the intrabiogeocenotic (tessera) level are related to the vegetation. The soils of the spruce and tall-grass tesseras are richer in nitrogen, calcium, and manganese as compared to the soils of the dwarf shrub-green moss, low-grass-dwarf shrub-green moss, and tussock grass-dwarf shrub tesseras.     

Nitrogen Isotopes in Soils and Plants of Tundra Ecosystems in the Khibiny Mountains

Eurasian Soil Science - The isotopic composition of nitrogen in soils and plants may be an indicator of transformation of its compounds and sources of N nutrition of plants. Natural 15N abundance...     

Artificial and natural radionuclides in soils of the southern and middle taiga zones of Komi Republic

Specific activities of artificial (¹³⁷Cs, ⁹⁰Sr) and natural (⁴⁰К, ²³²Th, ²²⁶Ra) radionuclides in background soils of southern and middle taiga of Komi Republic have been estimated with consideration for the landscape-geochemical features of the territory. It has been shown that their accumulation and migration in soils are determined by the following factors: position in relief, texture, and organic matter content. No anomalous zones with increased contents of radionuclides in soils have been revealed.     

The nitrogen regime and biological fixation of nitrogen in moss communities (the Khibiny Mountains)

In the vegetation belts of the Khibiny Mountains, the dynamics of the contents of mineral and easily hydrolyzable (according to Cornfield) nitrogen compounds in the litter and the nitrogen-fixing capacity of epiphytic cyanobacteria on dominant mosses were studied. The nitrogen regime of most moss species was shown to be self-supporting probably due to the intense assimilation of molecular nitrogen by epiphytic cyanobacteria (during the growing period, up to 28% of the total nitrogen content in plants) and the low organic matter production by mosses.     

Genetic features of soils on sorted sand deposits of different origins in the Kola Peninsula

Differences in the chemical composition of soils developed from sorted sands of different origins are revealed. The iron-illuvial podzols on rich glaciofluvial and marine sands are characterized by well-pronounced Al-Fe-humus differentiation of the Si, Al, and Fe in the soil profile. These soils are relatively similar in their bulk elemental composition. The difference between them is seen in the degree of differentiation of the soil profiles; it is stronger in the soils developed from glaciofluvial deposits. This is particularly true with respect to the oxalate-soluble iron and aluminum hydroxides. The deposits derived from the red-colored Tersk sandstone and processed by the sea (in the coastal zone of the White Sea) have the poorest chemical composition. In the soils developed from them, the differentiation of oxalate-soluble compounds is slightly pronounced (for Fe) or completely absent (for Si and Al). These soils can be classified as podzolized ferruginous red-colored psammozems (within the order of poorly developed soils) with the following horizons: O-Ce-Cf-C. The Ce horizon has the features of podzolization, and the Cf horizon has some features attesting to the illuvial accumulation of Fe. The profile of these soils inherits a reddish tint from the parent material.     

Humus of soils of the Altai Mountains

Data on the humus composition and specific features of soils in the Altai Mountains obtained in the long-term studies initiated by R.V. Kovalev are discussed. The average statistical values for the content of the main humus components and their ratios in different soil types were obtained by processing the data on 307 soil pits. The comparison of the soils belonging to the same type and occurring in the northwestern, central, and southeastern regions of the Altai Mountains in terms of the C ha/C fa ratio (one of the integral indices of the humus composition) showed that there were no significant differences between them. The overlapping intervals of the average values of this ratio testified to this fact. For instance, the average C ha/C fa ratios in the mountain tundra soils of the regions mentioned amounted to 0.70 ± 0.03; 0.72 ± 0.02; and 0.69 ± 0.03, respectively, and, in the mountain meadow soils, they amounted to 0.67 ± 0.03; 0.69 ± 0.04; and 0.67 ± 0.03, respectively. The mountain brown forest soils that are components of the soil cover only in the northwestern and central regions also differ insignificantly by this parameter (0.88 ± 0.05 and 0.89 ± 0.03, respectively). In the soils of the Altai Mountains, the dependence between the portion of humic acids and the mean annual air temperature (HA (%) = 29.54 + 1.06T(°C), r = 0.71) and the ratio of the portion of fulvic acids to the mean annual precipitation (FA (%) = 9.70 + 0.029W, r = 0.74) was shown to be similar to those in all the soils of mountainous southern Siberia. These facts enabled us to apply regression equations for a quantitative reconstruction of the paleoclimate components according to the humus composition. Original Russian Text ￠ M.I. Dergacheva, E.I. Kovaleva, N.N. Ryabova, 2007, published in Pochvovedenie, 2007, No. 12, pp. 1416–1421.     

The abundance of natural nitrogen 15 in the organic matter of soils along an altitudinal gradient (chablais, haute savoie, France)

The¹⁵N content of total nitrogen from a soil sequence derived from flysch (Eutrophic brown soil, Mesotrophic brown soil, Ochreous brown soil, Ochreous podzolic soil) is shown to increase downwards from the litter (negative δ¹⁵N) to the B and C horizons (δ¹⁵N + 5‰). This evolution is negatively correlated with C and N content and the C/N ratio. This evolution is related with biodegradation and humification processes.     

The Effect of Ericoid Mycorrhizal and Ectomycorrhizal Plants on Soil Properties of Grass Meadow in Tundra of the Khibiny Mountains

Eurasian Soil Science - The study of the effect of plants with different type of mycorrhizal symbiosis on carbon, nitrogen, and phosphorus transformation in soils is important in view of the...     

Erodibility and runoff-infiltration characteristics of volcanic ash soils along an altitudinal climosequence in the Ecuadorian Andes

Soil erosion is a widespread phenomenon in Andean South America, where many regions are covered with soils derived from volcanic parent materials. Climate-induced differences in the genesis of these soils have been demonstrated along toposequences on volcanic slopes. This research was conducted to study the impact of such differential pedogenesis on erodibility and runoff-infiltration characteristics along an altitudinal Entisols–Inceptisols–Andisols sequence in the Andes of northern Ecuador. Surface soils were packed into small pans and placed on a 9% slope, and a simulated rainstorm with varying intensities was applied for a duration of 30 min. The runoff-erosion behaviour of the studied volcanic ash soils is strongly affected by their pedological development. Accumulation of organic matter and precipitation of active amorphous materials at high elevations have led to the formation of well-developed Andisols with very stable aggregate structure. These soils remain wettable when air-dried, show very high infiltration capacity and, consequently, low potential for runoff generation and soil erosion. Low organic matter contents and absence of active amorphous materials at low elevations have led to the formation of weakly aggregated Entisols and Inceptisols. These soils are susceptible to surface crusting, which lowers their infiltration capacity and increases their erodibility. However, in comparison with other soils of different origin and composition, the interrill erodibilities determined for these more erodible low-elevation soils are classified as low. The findings of this study suggest that upland soil erosion is not a major threat to sustainability in the studied volcanic landscape, which is generally confirmed by field observations.     

Actinomycete complexes in soils of industrial and residential zones in the city of Kirov

The number, diversity, and structure of the actinomycetal complexes in the soils of the industrial and residential zones of the city of Kirov are considered. The total content of mobile cadmium, zinc, lead, iron, and nickel in the soils of the industrial biotopes was 1.8 and 6.0 times higher than their concentration in the soils of the residential and background zones, respectively. In the heavy metal (HM)-polluted soils, the share of actinomycetes in the total number of prokaryotes and the relative abundance of the micromono-spores in the actinomycetal complex were much higher and the species diversity of the streptomycetes was lower than these characteristics in the soils of the residential zone. The differences in the composition of the mycelial prokaryote complexes appear to be related to the selective resistance of some of their representatives to heavy metals. The possibility to select the strains resistant to HMs and suitable for use in the bioremediation of polluted soils is considered.     

青藏高原土壤主量元素在2800米高程梯度上的分异特征

There are a series of special mountain soils on the Tibetan Plateau of China in an alpine environment for the high altitude. However, very few studies have focused on major soil elements in relation to soil formation in this area. Aluminum (Al), iron (Fe), calcium (Ca), sodium (Na), potassium (K) and magnesium (Mg) contents of 237 topsoil samples covering a 2.8-km altitudinal gradient in uncultivated areas along the Qinghai-Tibet Railway of China were measured using inductively coupled plasma atomic emission spectroscopy. The spatial distribution of the elements and its relationship to the parent rocks and climatic parameters were analyzed. Soils along the gradient are derived from a range of parent materials, but most are less than 30 cm deep with little development (Cambisols). Soil Al, Fe and Mg contents showed a decreasing trend from the start station (Xining Station) to end station (Lhasa Station) of the Qinghai-Tibet Railway, whereas soil K and Na contents were relative stable from Xining Station to the Kunlun Mountains and then increased gradually. Soil Ca content was lower in the southern part of Tanggula Mountains. The major soil element contents clearly reflected the parent rock and climatic influences. Soils with higher Ca content appeared in areas with Ca-Mg carbonate rocks, soils with higher Al were found in areas with silicate-rich and high-Al silicate clastic rocks and silicate-rich aluminosilicate loose sediments. Soils with higher K and Na contents appeared in areas with high-K, high-Na and silicate-rich aluminosilicate rocks. Soil Na and K contents were affected by temperature, whereas the contents of Mg, Fe, Ca and Al were more affected by precipitation. Soil Na and K contents increased with increasing temperatures, whereas the contents of Mg, Fe, Ca and Al decreased with increasing precipitation. This analysis provides a relationship between soil properties and rapidly changing environmental conditions. The data can be used to investigate the effect of the climate or land use change on soil properties.     

长白山地区不同植被下土壤酸度状况

The acidity regimes of representative soils on the north slope of the Changbai Mountains were examined through determinations of pH and pCa of the soil paste as well as in-situ determinations,For soils under broad-leaf forest or broad-leaf-Korean pine forest,the pH decreased from the litte to lower layers gradually until it did not change or decreased further slightly .For soils under coniferous of Erans birch forest,ther was a minimum in pH at a depth of 3-6 cm where the content of humus was high,The pCa increased gradually from the soil surface downward to a constant value.The lime potential(pH-0.5pCa) showed a similar trend as the pH in its distribution.For a given soil,the measured pH value of the thick paste,ranging from 4.5 to 5.5,was lower by about 0.5 units than the value determined by the conventional method with a water to soil ratio of 5:1 ,The pH determined in situ was even lower.It was found that there was a firly close relationship between soil acidity and the type of vegetation.The pH showed a trend of decreasing from soils under broda-leaf forest through broad-leaf-conifer mixed rorest and coniferos forest to Ermans birch forest,and the pCa showed an opposite trend in variation.     

Specific features of the humus status in soils of Buryatia

The humus content in soils of Buryatia varies significantly in dependence on the local hydrothermic conditions. All the studied soils are characterized by a relatively short humus profile, a sharp drop in the humus content down the soil profile, considerable amounts of the humin fraction and the fraction of humic acids bound with sesquioxides, and a moderate humus enrichment with nitrogen.     

罗浮山土壤发生特性与系统分类研究

为了解我国南亚热带山地土壤的发生特性及其在中国土壤系统分类中的归属,以罗浮山不同海拔高度的10个代表性剖面为研究对象,分析土壤发生特性,确定诊断层和诊断特性,对土壤进行系统分类,并在高级分类单元级别上进行了中国土壤系统分类、美国土壤系统分类和世界土壤资源参比基础之间的参比研究。研究表明:土壤干态色调主要为10YR,质地属壤土大类,粉黏比为0.42 ~ 2.62,多数剖面土壤粉黏比小于1.0;土壤酸性强（水浸提pH 3.69 ~ 4.94）,CEC为4.43 ~ 25.68 cmol (+) kg?1,盐基饱和度（2.27% ~ 16.25%）低,交换性酸（1.35 ~ 6.41 cmol (+) kg?1）以交换性Al3+为主,多数土层铝饱和度超过了80%;土壤矿质元素以Si、Al、Fe为主,黏粒硅铝率（Sa）、黏粒硅铁铝率（Saf）均小于2.0,各剖面B层Al、Fe、P、Ti在黏粒中富集明显,Fe富集率稍大于Al;在土壤垂直带谱上,湿润富铁土一般分布于800 m以下,常湿富铁土介于800 ~ 1200 m,常湿雏形土在1200 m以上。罗浮山土壤具有明显的脱硅富铁铝化特性,具有有机碳累积明显、酸性强、盐基饱和度低、铝饱和度高等特点;归属为2个土纲、3个亚纲、4个土类和6个亚类。     

Characteristics of bacteria in the forest soils under natural vegetation

Characteristics of the predominant bacteria isolated in November and May from the forest soils of both dry and wet types under natural vegetation were studied.

Although Gram-negative rods were the most abundant bacteria in both soil types and in both seasons, their contents were less and other bacteria especially spore-forming ones increased in May.

Among Gram-negative rods in the soil of the dry type in November, the most predominant was those with nonchromogenic rods motile with polar flagella which grew in a simple synthetic media containing glucose or p-hydroxybenzoate and ammonium as the sole carbon and nitrogen sources. In May, the ratio of the bacteria which require amino nitrogen or those with more chomplex nutritional requirement increased. In the soil of moderately wet type, the difference in kinds of bacteria between the two seasons was not so clear as that in the dry type.

Most of Bacillus species obtained in these soils were those requiring amino acids or other growth factors among which B. cereus was most abundant.