scholarly journals Diagnostic problems of elementary soil processes and profile-differentiated soils of the Precarpathian region

2016 ◽  
Vol 17 (1-2) ◽  
pp. 40-48
Author(s):  
I. S. Smaga
Keyword(s):  
Chemical Composition ◽  
Soil Properties ◽  
Diagnostic Criteria ◽  
Humic Acids ◽  
Soil Type ◽  
Soil Profile ◽  
Laboratory Simulation ◽  
Soil Processes ◽  
Acid Base ◽  
Genetic Nature

Present condition, scientific concepts and ways of further development of diagnosis problem of elementary soil processes and genetic nature profiled-differentiated gleyed soils of the Pre-Carpathian region, known as brownish-podzolic, brownsoil-podzolic and sod-podzolic, based on stable indicators of soil properties are studied. Eluvial-illuvial differentiation nature of the soil profile of the studied soils is founded. The aim of research was to develop criteria for the diagnosis of elementary soil processes and genetic nature profiled-differentiated soil deposits of Ciscarpathia and discovering of the parameters of the relevant indicators of soil properties. The soil profile with his characteristic set of genetic horizons and morphological characteristics can result from taking place of both various set (kit) of ESP and of varying intensity of individual processes (complex ESP). Formation of genetic soil type is caused by the course of the profile forming (main) process with the possible participation of several (related) processes. An important condition for the diagnostic determination of profile-differentiated soils in the Ciscarpathia is the search for reliable diagnostic criteria for basic elementary soil processes (ESP) which play a crucial role in the genesis and determine their macromorphological characteristics: lessivage, podzolisation, gleying and eluvial-gleying processes. Diagnostic criteria of the elluvial processes resulted in gross chemical composition of the soil (molecular ratio), particle size distribution (loss sludge) and mineralogy silt fraction (montmorillonite content) were tested. The criteria for establishing genetic origin of the Pre-Carpathian soils, podzolization and eluvial-gley processes detection and their possible parameters were suggested. Followed the impact of the prevailing development of individual creating profile elementary soil processes (podzolization, eluvial-gley and gleying) by laboratory simulation modeling of soil regimes that are conducive to them (washing, water stagnant and contrast) for evaluative indicators of acid-base soil buffer and made the conclusions about the possibility of these processes isolation. Eluvial-illuvial differentiation of Ciscarpathia typical soils is coursed by passage of profile forming process of podzolisation (acid hydrolysis, podzolic) and related from the group of eluvial - eluvial-gleying process and lessivage. They are diagnosed by the gross grain and chemical composition of the soil and the content of montmorillonite. Brown soil forming processes have a significant impact on the formation of humus status and physical and chemical properties of the studied soil. Substantiated differences forming the group composition of humus and fractional composition of humic acids of soils formed underbrownsoil formation processes from the sod soils type (the ratio of humic acids to fulvic acid, gumatcalcium content, optical density of humic substances). Advantages and disadvantages of using quantitative identification criteria - profile humus accumulation factor in the genetic diagnosis of soil type are analyzed. In the conditions of wash and contrasting modes of moisture, causing the priority development processes of podzolisation and  gleye- eluvial respectively a similar trend of formation of acid-base buffer capacity of soil and similar parameters of evaluating indicators within the soil profile are observed. It is impossible to separate the processes of podzolisation and  gleye- eluvial using the indicators of acid-base buffering. Describing of profile structure, morphological and genetic traits of genetic horizons, the profile distribution of acid-base buffering indicators (even without the use of criteria based on gross chemical and grain composition and content of clay minerals) help to clear identify brownish-podzolic gley soils of Ciscarpathia.

Earthquake Microzoning from Soil Properties

1993 ◽  
Vol 9 (2) ◽  
pp. 209-231 ◽  
Author(s):  
A. P. W. Hodder ◽  
M. Z. Graham
Keyword(s):  
Shear Strength ◽  
New Zealand ◽  
Linear Regression ◽  
Soil Properties ◽  
Shear Wave Velocity ◽  
Soil Type ◽  
Soil Profile ◽  
Soil Structure ◽  
Viscous Damping ◽  
Extent Of Damage

The extent of damage caused by an earthquake in Wellington, New Zealand, in 1968 to buildings erected on a variety of regoliths and foundation materials is correlated with the thickness of the regolith, the depth to the water table and semi-quantitative parameters derived from soil profile descriptions, particularly related to soil type and soil structure. From linear regression correlations, the expected damage for a comparable earthquake elsewhere can be determined. The model was tested for soil data for the Edgecumbe area, hit by a damaging earthquake in 1987. The predictions were sufficiently in accord with observations to suggest that soil properties that reflect the geotechnical properties of the upper parts of the regolith, particularly those that measure the shear strength, shear wave velocity and viscous damping of that material, may be useful for earthquake microzoning purposes in areas where there is a considerable thickness of unconsolidated materials above bedrock.

Analysis of Structural Features of Humic Acids Fractions after Mechanochemical Modification

2015 ◽  
Vol 1085 ◽  
pp. 3-6 ◽  
Author(s):  
Malika P. Mirzobekzoda ◽  
Elizaveta V. Maltseva ◽  
Natalya S. Shekhovtsova
Keyword(s):  
Chemical Composition ◽  
Ir Spectroscopy ◽  
Humic Acids ◽  
Fulvic Acids ◽  
Structural Features ◽  
Acid Base ◽  
Structural Composition ◽  
Mechanochemical Modification ◽  
The Impact ◽  
First Time

Humic substances are the major components of soil, peat and brown coal. They can be fractionating into fulvic acids (FA), brown humic acids (BHA) and gray humic acids (GHA). In this work we investigated the influence of mechanochemical modifications on structural composition of HAs main fractions using the methods of IR and 1H MRS spectroscopy. The IR spectroscopy results has shown that HA has different chemical composition in comparison with GHA and BHA. Potentiometric titration showed that mechanoactivation (MA) with thiourea increases the amount of oxygen-containing groups up to 2.5. For the first time we studied the impact of modifying agent of thiourea on the structural composition and acid-base properties of HAs major fractions - GHA and BHA during the mechanoactivation process.

Ants Visible from Space Influence Soil Properties and Vegetation in Steppe Rangelands of Iran

Sociobiology ◽  
2016 ◽  
Vol 63 (4) ◽  
pp. 1063
Author(s):  
Jonathan David Majer ◽  
Donat Agosti
Keyword(s):  
Chemical Composition ◽  
Species Composition ◽  
Soil Properties ◽  
Plant Species ◽  
Plant Diversity ◽  
Soil Profile ◽  
Vegetation Structure ◽  
Cumulative Effect ◽  
Ant Nests

Messor nests in Iranian steppe rangelands can be so large that they are visible from space. When compared with reference soils, nest soil is higher in nutrients and lower in pH. Ant nests also homogenise the nutrients throughout the upper soil profile, although this effect diminished when nests are abandoned. The denuded circles around nests are surrounded by rings of vegetation that differ in species composition from that of the surrounding vegetation, while abandoned nests are colonized by a different range of plant species. Data on the density and abundance of Messor cf. intermedius nests indicate that the soil in less than 1% of the area is impacted, although the cumulative effect of so many nests influences the plant species and vegetation structure of the region. The data indicate the importance of these ants in altering soil chemical composition and plant diversity, which could have flow-on effects to the diversity of animals.

scholarly journals Properties of humic acids depending on the land use in different parts of Slovakia

2021 ◽  
Author(s):  
Magdalena Banach-Szott ◽  
Bozena Debska ◽  
Erika Tobiasova
Keyword(s):  
Land Use ◽  
Organic Carbon ◽  
Size Distribution ◽  
Humic Acids ◽  
Forest Ecosystem ◽  
Soil Type ◽  
Soil Types ◽  
Organic Matter Quality ◽  
Degree Of Maturity ◽  
Effects Of Land Use

AbstractMany studies report organic carbon stabilization by clay minerals, but the effects of land use and soil type on the properties of humic acids (HAs) are missing. The aim of the paper is to determine the effects of land use and soil types on the characteristics of HAs, which have a considerable influence on organic matter quality. It was hypothesised that the effect of the land use on HAs properties depends on the particular size distribution. The research was performed in three ecosystems: agricultural, forest, and meadow, located in Slovakia. From each of them, the samples of 4 soil types were taken: Chernozem, Luvisol, Planosol, and Cambisol. The soil samples were assayed for the content of total organic carbon (TOC) and the particle size distribution. HAs were extracted with the Schnitzer method and analysed for the elemental composition, spectrometric parameters in the UV-VIS range, and hydrophilic and hydrophobic properties, and the infrared spectra were produced. The research results have shown that the properties of HAs can be modified by the land use and the scope and that the direction of changes depends on the soil type. The HAs of Chernozem and Luvisol in the agri-ecosystem were identified with a higher “degree of maturity”, as reflected by atomic ratios (H/C, O/C, O/H), absorbance coefficients, and the FT-IR spectra, as compared with the HAs of the meadow and forest ecosystem. However, as for the HAs of Cambisol, a higher “degree of maturity” was demonstrated for the meadow ecosystem, as compared with the HAs of the agri- and forest ecosystem. The present research has clearly identified that the content of clay is the factor determining the HAs properties. Soils with a higher content of the clay fraction contain HAs with a higher “degree of maturity”.

Relating Ion Binding by Fulvic and Humic Acids to Chemical Composition and Molecular Size. 2. Metal Binding

2001 ◽  
Vol 35 (12) ◽  
pp. 2512-2517 ◽  
Author(s):  
Iso Christl ◽  
Chris J. Milne ◽  
David G. Kinniburgh ◽  
Ruben Kretzschmar
Keyword(s):  
Chemical Composition ◽  
Humic Acids ◽  
Metal Binding ◽  
Molecular Size ◽  
Ion Binding

Sensitivity analysis of geotechnical site conditions effect on the seismic response of a saturated inhomogeneous poroviscoelastic soil profile

2018 ◽  
Vol 15 (6) ◽  
pp. 661-677 ◽  
Author(s):  
Toufiq Ouzandja ◽  
Mohamed Hadid
Keyword(s):  
Soil Properties ◽  
Seismic Response ◽  
Pore Water ◽  
Soil Profile ◽  
Water Saturation ◽  
Free Field ◽  
Response Spectra ◽  
Response Analysis ◽  
Content Type ◽  
Linear And Nonlinear

Purpose This paper aims to present the investigation of the linear and nonlinear seismic site response of a saturated inhomogeneous poroviscoelastic soil profile for different soil properties, such as pore-water saturation, non-cohesive fines content FC, permeability k, porosity n and coefficient of uniformity Cu. Design/methodology/approach The inhomogeneous soil profile is idealized as a multi-layered saturated poroviscoelastic medium and is characterized by the Biot’s theory, with a shear modulus varying continuously with depth according to the Wichtmann’s model. Seismic response analysis has been evaluated through a computational model, which is based on the exact stiffness matrix method formulated in the frequency domain assuming that the incoming seismic waves consist of inclined P-SV waves. Findings Unlike the horizontal seismic response, the results indicate that the vertical one is strongly affected by the pore water saturation. Moreover, in the case of fully saturated soil profile, the same vertical response spectra are found for the two cases of soil behavior, linear and nonlinear. Originality/value This research is a detailed study of the geotechnical soil properties effect on the bi-directional seismic response of saturated inhomogeneous poroviscoelastic soil profile, which has not been treated before; the results are presented in terms of the peak acceleration ratio, as well as the free-field response spectra and the spectral ratio (V/H).

scholarly journals The nutritive value of the indigenous grasses of Surinam.

1963 ◽  
Vol 11 (4) ◽  
pp. 295-307
Author(s):  
J.G.P. Dirven
Keyword(s):  
Chemical Composition ◽  
Dairy Cattle ◽  
Mineral Composition ◽  
Soil Type ◽  
Growth Stage ◽  
Nutritive Value ◽  
Ionic Balance ◽  
Average Chemical Composition

Data are given on the average chemical composition of herbage from natural pastures in relation to soil type and the feed requirements of dairy cattle, and on the composition of various species and the effects of growth stage. Mineral composition and ionic balance are discussed.-R.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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