No 95 (2018)
D. Arrouays,
A. C. Richer-de-Forges,
A. B. McBratney,
A. E. Hartemink,
B. Minasny,
I. Savin,
M. Grundy,
J. G. B. Leenaars,
L. Poggio,
P. Roudier,
Z. Libohova,
N. J. McKenzie,
H. van den Bosch,
B. Kempen,
V. L. Mulder,
M. Lacoste,
S. Chen,
N. P. A. Saby,
M. P. Martin,
M. Román Dobarco,
I. Cousin,
T. Loiseau,
S. Lehmann,
M. Caubet,
B. Lemercier,
C. Walter,
E. Vaudour,
C. Gomez,
G. Martelet,
P. Krasilnikov,
P. Lagacherie
3-23 4851
Abstract
Soils have critical relevance to global issues, such as food and water security, climate regulation, sustainable energy, desertification and biodiversity protec-tion. As a consequence, soil is becoming one of the top priorities for the global environmental policy agenda. Conventional soil maps suffer from large limita-tions, i.e. most of them are static and often obsolete, are often generated at coarse scale, and can be uneasy to handle. Digital Soil Mapping has been developed as a solution to generate high-resolution maps of soil properties over large areas. Two projects, GlobalSoilMap and SoilGrids, presently aim at delivering the first generation of global, high-resolution soil property fine grids. In this paper, we briefly describe the GlobalSoilMap history, its present status and present achievements, and illustrate some of these with (mainly) French examples. At given moment there is still an enormous potential for forthcoming research and for delivering products more helpful for end users. Key here is the continuous progress in available covariates, in their spatial, spectral and temporal coverage and resolution through remote sensing products. All over the world, there is still a very large amount of point soil data still to be rescued and this effort should be pursued and encouraged. Statistically advances are expected by exploring and implementing new models. Especially relevant are spatial-temporal models and contemporary Artificial Intelligence for handling the complex big data. Advances should be made and research efforts are needed on estimating the uncertainties, and even on estimating uncertainties on uncertainties. Attempts to merge different model strategies and products (for instance deriving from different covariates, spatial extents, soil data sources, and models) should be made in order to get the most useful information from each of these predictions, and to identify how controlling factors may change depending on scales.
23-40 926
Abstract
During the model experiment we exposed samples from surface layer of leached chernozem, grey forest and soddy-podzolic soils to study the impact of raindrop action on their surface. According to our results, surface of leached chernozem and grey forest soil transformed similarly forming the crust separated by the cracks. The crust consisted of light (washed silt fraction) and dark (compacted fine material) areas. As for the soddy-podzilic soil, we observed surface accumulation of sand and washed mineral grains. Surface image classification showed that cracks generally tended to increase in area during the surface drying. However, leached chernozem cracked quicker and heavier compared to grey forest soil. In addition, the proportion between light and dark areas of the crust for these two types of soil changed differently as well. In conditions of different transformation cycles divided by heavy rainfalls, the changes of cracks position and the increase of light crust area was observed, while dark area moved to the cracks. Such spatial rearrangement resulted in the increase of average reflectance in RGB channels. The inequality between reflectance in different channels increased as well. During the experiment significant surface lightening occurred. It mainly affected the light area of crust and led to significant rise in reflectance in red channel.
THE SPATIAL DIFFERENTIATION OF SOIL SALINITY AT THE YOUNG SALINE COASTAL PLAIN OF THE CASPIAN REGION
M. V. Konyushkova,
S. Alavipanah,
A. Abdollahi,
S. Hamzeh,
A. Heidari,
M. P. Lebedeva,
Yu. D. Nukhimovskaya,
I. N. Semenkov,
T. I. Chernov
41-57 1099
Abstract
The study is focused on the pattern of soil salinity at the young loamy coastal plains of the Caspian Sea in Russia and Iran which were released from water less than 300 years ago. At two key sites of 45×30 m (Russia) and 25×20 m (Iran), the soil sampling with 1 to 5 m grid was performed to the depth of 1 m. The electrical conductivity (1 : 2.5) was measured in soil samples and soil sa-linity maps were compiled. Soils are represented by solonchaks with 2–3% of salts in the top layer or highly saline soils partly leached in the upper 5–10 cm. The ground water table is shallow (2–2.5 m). The studied sites are different in terms of climate, microtopography, and vegetation cover but spatial differentiation of soil salinity is quite similar what is evidenced from the similar distributions (mean values and variance) of electrical conductivity in almost all studied depths. The redistribution of salts is mainly observed in the upper 50 cm with the maximal manifestation in the upper 5 cm.
58-70 988
Abstract
The analysis of the Soil Map of the Russian Federation (1 : 2.5 M scale, 1988) with identification of soils shown in each polygon in categories of the classification system of Russian soils (2004, 2008) is the first stage of work on creating the new digital soil map of Russia. It demonstrated the need to introduce a number of amendments to the classification system. They concern the definitions and names of diagnostic horizons and diagnostic features of soils. Thus, it is suggested that the mucky–dark humus horizon AH should be renamed as the mucky–humus horizon (as its properties do not fit the definition of the dark humus horizon in the system). Several new diagnostic features are introduced; for permafrost-affected soils, supra-permafrost accumulation of organic matter is designated by symbol cro. It is also suggested that the lists of soils at the subtype level, which reflects the development of certain diagnostic features, should be more flexible without their "rigid" linking to the given types. The aim of these changes is to reflect the accumulated information on the diversity of soils in Russia as displayed on the Soil Map of the Russian Federation (1988) and in the State Register of Soil Resources more adequately in the new classification system of Russian soils.
71-89 886
Abstract
Climate warming results in significant changes in the structure and functioning of terrestrial ecosystems. The ecosystems situated near oil-well gas flares may be used as model ones for studying warming effect on soil and vegetation. By contrast to regular manipulation experiments where ecopysiological factors are modified or controlled artificially, we used anthropogenically affected condi-tions caused by the gas flaring. Our research was aimed to assess the warming and desiccation effect on the stoichiometric ratios of the principle nutrients (C : N : P) in pine phytomass, soil and soil microbial biomass. Soil organic matter (SOM) and dying microbial biomass were found to be exposed to the increased rate of mineralization under conditions of the abiotic stress. In addition, the de-crease of relative С content in sustainable SOM pools occured along with the increase of C content in the most labile water-soluble pools. Accelerated SOM mineralization decreasing C : N with respect to phosphorus ratio in soil and soil microbial biomass was sufficiently intensified by the decrease in C : N : P in pine needles. Thus, studying changes in stoichiometric ratios of biophylic ele-ments as affected by abiotic factors seems to be prospective and promising methodological approach for predicting terrestrial ecosystem transformations under global climate changes.
90-98 774
Abstract
The level of genus in the “Classification and diagnostics of soils of the USSR”, 1977 is discussed as applied for diverse purposes. It was very often required in soil surveys to indicate details of soil processes, current or inherited features when compiling small- and medium-scale soil maps. In the recent classification of Russian soils, genus level is mostly used for the analytical characteristics of soils, whereas its former functions were transferred to the subtype level; for example, red color of parent material corresponds to “red-profile” subtype. In the updated classification system of soils of Russia, it is proposed to expand the sphere of the genus level application over a broader set of phenomena, to update the criteria for different genera, and to arrange genera in groups like those for genetic properties, which serve as criteria to identify subtypes. The following preliminary groups of genera may be specified: analytical including genera related to chemical soil pollution, lithological (particular parent materials), temporal for ephemeral features, pedogenetic – disclosing or indicating mechanisms of soil processes.
99-124 835
Abstract
In the physical fractions of gray forest soil (agroseraya typical): clay (up to d = 0.001 мм), light (lighter than 2 g/cm3) and the residue fraction, the contents of total carbon and phosphorus (total, organic and mineral forms) were determined. We have found that fertilizing increased the content of total carbon in the soil after 20 years of rotation system. Content of light fractions also increased. Mineral fertilizers reduced the content of organic carbon in the light fractions of this soils, this effect requires further study. The application of lime and manure reduced the content of clay fraction, but increased the content of total carbon in it. The yield of cereals and perennial grasses depended little on the amount of total carbon in the soil and its clay and light fractions. In this case, its feedback is established with the content of light fraction and carbon in the residue. The yield of grain crops is proportional to the proportion of mineral phosphates and weakly dependent on organic forms in the subsurface horizon. In general, the yield of cereals increases with the application of mineral fertilizers. The effect of manure was less pronounced.
I. A. Tikhonovich,
T. I. Chernov,
A. D. Zhelezova,
A. K. Tkhakakhova,
E. E. Andronov,
O. V. Kutovaya
125-153 1175
Abstract
Using high-throughput sequencing, we performed a full-profile analysis of the taxonomic structure and diversity of prokaryotic communities of zonal soil series: sod-podzolic, dark gray, typical chernozem, brown soil, meadow-chestnut soil and solonets. Phyla Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Gemmatimonadetes, Planctomycetes, Proteobacteria and Verrucomicrobia formed up to 95% of prokaryotic communities in all studied soil horizons. Phyla Proteobacteria and Actinobacteria and archaeal phylum Thaumarchaeota dominated in all soils. We revealed the trends of changes in the representation of bacterial phyla in the soils of the zonal range from taiga to dry-steppe: a decrease of Acidobacteria and an increase of Actinobacteria in the upper horizons. The diversity indices of the prokaryotic communities of different genetic horizons of the studied soils were evaluated. In all soils, a decrease in diversity indices with the depth of the horizon was revealed. In all soils, a decrease in diversity indices with depth of the horizon was found, with a rare and slight increase in some lower horizons: structural metamorphic (BM), textural (BT) or accumulative carbonate (BCA) horizons. When examining the prokaryotic communities of soils with different genesis, no determining influence of pH and organic matter contents on the diversity indices was found. Differences in the taxonomic structure and diversity of prokaryotic communities of soils of different bioclimatic zones were presented due to a combination of factors: the difference in chemical and physical properties of soils, as well as in water and temperature conditions.
ISSN 0136-1694 (Print)
ISSN 2312-4202 (Online)
ISSN 2312-4202 (Online)