Bleached Soil Research Articles

UTILIZATION OF SPENT BLEACHING EARTH WASTE IN SOIL-CEMENT STABILIZATION FOR ROAD FOUNDATION LAYERS IN TERMS OF THE MECHANICAL PROPERTIES OF SOIL

Various studies have been carried out to improve the parameters of soil mechanical properties. Efforts to improve the mechanical properties of the soil can be carried out in multiple ways, including automated means through compaction and chemical means through the addition of cement base materials. To improve the stability and properties of the subgrade soil, the cement base material that is commonly used is Portland Composite Cement (PCC). In several studies, apart from cement base materials, waste base materials have also been used for stabilization subgrade. This includes using bleached soil residues and rice husk ash as additives to stabilize the soil. The results showed that the use of soil bleaching waste in soil cement stabilization can be used to improve the mechanical properties of the embankment soil and the composition of the soil bleaching waste mixture so that mechanically, it is proven to provide the most effective improvement so that it can be used for road foundation layers made of cement soil. As part of this research, many tests can be carried out on normal and stabilized soils. Various percentages of SBE are 5%, 10%, 15%, 20%. PCC is introduced into the soil at a rate of 8% of the dry weight of the soil.

Last Glacial Maximum active layer thickness in Western Europe, and the issue of ‘tundra gleys’ in loess sequences

AbstractLate Marine Isotope Stage (MIS) 3 and MIS 2 loess–palaeosol sequences in Western Europe comprise alternating loess layer and 3‐ to 30‐cm‐thick bleached soil horizons with Fe–Mn oxide precipitations, which are usually interpreted as waterlogged active layers and referred to as ‘tundra gleys’. Active layer thickness data derived from a regional climate model simulation and the fossils (shells, earthworm granules) found in ‘tundra gleys’ argue against such an assumption. Most of these horizons better correspond to Fe‐depleted, slightly humic topsoil horizons or subsurface eluvial horizons and should be referred to as (incipient) Ag or Eg horizons. They formed during climate ameliorations associated with vegetation (cryptogams, herbs) development, possibly limited by long‐lasting snow cover. Strong mixing usually occurred in these horizons due to the activity of anecic earthworms and frost activity.

Research on the sensitivity of parameters and calibrates DNDC model for calculating emissionsfrom paddy rice cultivation activities

This study estimates the sensitivity of parameters to serve the adjustment and construction of standard parameters in the Decomposition - Denitrification (DNDC) model when calculating greenhouse gas emissions from rice cultivation on alluvial, alkali, acid-sulfate, and bleached soils of Red river delta, Vietnam. The research results show that the following parameters: bulk density, clay fraction, microbial activity index, soil organic carbon (SOC), temperature, conductivity, fertilization of urea, and porosity have a high sensitivity for the calculation of CH4 emissions; the following parameters: pH, drainage efficiency, depth of water retention layer, field capacity, initial nitrate and ammonium concentrations at surface soil, and rainfall have low sensitivity and less influence for the calculation of CH4 emissions; the wilt moisture and salinity index have no effect on CH4 emissions. In case of N2O emissions, the following parameters: amount of manure, clay fraction, microbial activity index, pH, initial nitrate concentration at surface soil, bulk density, SOC, field capacity, porosity and depth of water retention layer have a high sensitivity and more influence to N2O emissions; the following parameters: drainage efficiency, conductivity, initial ammonium concentration at surface soil, temperature, fertilisation of urea and rainfall have low sensitivity and less influence to N2O emissions; the wilting point and soil salinity index have no effect on N2O emissions. The results of model calibration show a good correlation between observed and simulated values in both spring and summer crops in 2018. The R2 of the spring and summer crops reach 0.86 and 0.79, the Nash-Sutclitffe efficiency index reaches 0.82 and 0.77 for CH4 emission; meanwhile, for N2O emission, these values are 0.62, 0.69, and 0.76, respectively. The study also found a model calibration parameter used to calculate greenhouse gas emissions from rice cultivation on alluvial, alkali, acid-sulfate, and bleached soils.

Changes in the fertility of meadow-brown bleached soil with long-term use of different fertilizer systems

The article presents the results of changes in the fertility of meadow-brown bleached soil in a long-term stationary experiment, laid down in 1941. It has been established that applying various systems of manure, lime, and mineral fertilizers in a single and double dose for 79 years improves the agrochemical soil properties. The content of organic matter in the variants of the manure-lime-mineral system with single and double doses of mineral fertilizers increased from 3.00% (control) to 3.11 and 3.21%, respectively. The phosphate regime of the soil improved when manure and lime were used together with mineral fertilizers in a doubled rate up to 137 mg/kg, and against liming with a single dose of mineral fertilizers up to 76 mg/kg, in the control variant - 15 mg/kg. Under the influence of lime and single norms of mineral fertilizers for wheat, the soil solution is deoxidized to a neutral value of 6.1, in the control variant without fertilizers the soil is subacid - 5.1. In the variant with the use of only double doses of mineral fertilizers, an increased yield of 4.8 t/ha and protein content of 13.8% in spring wheat was noted, in the control - 4.3 t/ha and 12.4%, respectively. The analysis of the correlation dependence of yield and protein per grain with a complex agrochemical property showed a strong direct relationship - r = 0.91; 0.78 respectively.

The atmospheric, vacuum and pressurized pyrolysis of used bleaching soils along with polymeric wastes to reach the valuable and economical fuels

The atmospheric, vacuum and pressurized pyrolysis of oil-rich bleached soil with polymeric wastes was investigated using a semi batch stirred reactor. Also, the gas chromatograph mass spectrometry (GC/MS) instrument was used to measure the hydrocarbon components containing paraffin, olefin, naphtehene and aromatic (PONA) and carbon number of the liquid product which the liquid products were classified to the different commercial fuel ranges. The atmospheric co-pyrolysis of oil-rich bleached soil with polyethylene tended to produce the heavy hydrocarbons while the pressurized pyrolysis decreased the products molecular weight obviously. The atmospheric co-pyrolysis of oil-rich bleached soil with polypropylene (PP) and polystyrene (PS) shifted to the medium and light fuels respectively. Also, manual filtration of the co-pyrolysis oils with the regenerated fluid cracking catalyst (FCC) at ambient temperature showed that the obtained oil from co-pyrolysis of polypropylene and bleached soil did not require re-filtration and had a very light color. The vacuum co-pyrolysis of bleached soil and the polymers produced more liquid with less cyclic compounds and lighter color compared to nitrogen pyrolysis. The pressurized pyrolysis of polyethylene and bleached soil using different carrier gases such as nitrogen, hydrogen, ethylene and propylene, tended to produce the lighter products in the commercial fuels range. Also, re-polymerization of the obtained liquid from co-pyrolysis, was carried out using benzoyl peroxide at 95 °C and atmospheric pressure, which only polystyrene and bleached soil co-pyrolysis product was able to take part in the polymerization process and two other co-pyrolysis products did not react with peroxide clearly.

The influence of different systems of fertilizer on the microelement’s composition of soil and grain of winter wheat in Primorsky Krai

This paper presents the effect of the aftereffect of mineral, organic and calcareous fertilizers on the agrochemical and environmental indicators of meadow-brown bleached soil of Primorsky Krai. The accumulation of microelements by the winter wheat grain is considered according to the variants of experience. Field experiments were carried out in 2011-2014 in the crop rotation of the agrochemical station of Federal Scientific Center of Agrobiotechnology in the Far East named after A.K. Chaika. The content of trace elements in soil and grain was determined on a Shimadzu AA-6200, atomic adsorption spectrophotometer. According to the results of our research, it was revealed that the aftereffect of various fertilizer systems affected the content of a number of gross and mobile forms of microelements in the studied soil. It is established that the soil does not prevent the accumulation of mobile forms of nickel, lead, cadmium, zinc, copper and cobalt in it. The ability to resist contamination of the food chain (system barrier), that is, the manifestation of the protective mechanisms of the grain, from nickel, copper and cobalt varies only slightly according to the variants of experience. For lead, cadmium and zinc, the barrier of the system is in the moderate degree of dispersion of data on the variants of experience, showing more effective protective capabilities on the variant with the aftereffect of the lime-organic fertilizer system, where the content of the latter reaches its maximum values.

Unraveling Hydrocarbon Microseepages in Onshore Basins Using Spectral–Spatial Processing of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Data

This study focuses on the spectral characterization of superficial effects caused by natural gaseous hydrocarbon (HC) escapes (microseepages) on onshore basins and means to detect the phenomena using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery. The Northern Tucano basin (NTB) (Brazil) displays archetypal onshore microseepages, and it is used here as a case study area. Regional HC geochemical data yielded from NTB soil samples helped to outline the strategies for imagery processing and assessment of results. We firstly devised a generic detection model for onshore basins in which microseepages indicated by HC geochemistry should spatially match a number of surface expressions with key remote sensing signatures, such as bleached soil and rocks (i.e., reduction in Fe3+ to Fe2+), concentration of specific clays (kaolinite), and carbonates (siderite) and geobotanical markers. These evidences guided the use of remote sensing data and information extraction techniques to find more sites favorable to host HC microseepages in the NTB. ASTER data processed through spectral mixing analysis and supervised and unsupervised neural network systems highlighted sites where features predicted in the detection model concurred seamlessly with geochemical anomalies. The approach also revealed other sites with similar characteristics, but for which no geochemical data exist. These sites are taken as new potential targets for the presence of microseepages and possibly HC reservoirs. The research demonstrated the potential of remote sensing data and spectral–spatial methodologies for economical, onshore detection of HCs for exploration purposes. Potential ramifications of the study include indirect detection of gaseous HC reservoirs in terrestrial planets (fostering the search for signs of life) and depiction of non-negligible, replenishable continental sources of HC emissions on Earth that may contribute to global warming.

Caracterização de microexsudações de hidrocarbonetos na Bacia do Tucano Norte (BA) por geoestatística, classificação hiperespectral e redes neurais

This study focus on the characterization of hydrocarbon microseepages in the northern Tucano Basin (Bahia State, Brazil), using geostatistical analysis of regional hydrocarbon geochemical data yielded from soil samples and digital processing of Enhanced Thematic plus (ETM+/Landsat7 satellite) and Advanced Spaceborne Thermal Emission and Reflection Radiometer imagery (ASTER/Terra satellite). A theoretical detection model was devised for the study in which gas anomalies (seeps) indicated by hydrocarbon geochemistry should spatially match a number of surface expressions such as the presence of bleached soil and rocks (i.e., reduction of Fe 3+ to Fe 2+ ), geobotanical markers and concentration of specific clays (kaolinite) and carbonates (siderite). These indirect evidences were employed for the application of remote sensing data and information extraction techniques in order to locate sites more favorable to host hydrocarbon seeps in the Tucano Basin. The ETM+ data was processed through the pseudo-ratio technique - an adaptation of the classic principal components analysis. The ASTER data was processed through the Spectral Angle Mapper and the Mixture Tuned Matched Filtering (techniques commonly used for the classification of hyperspectral data; here adapted for multispectral data) and via a pioneer approach by means of three different neural network systems (Fuzzy Clustering, Radial Basis Functional Link Network, and Probabilistic Neural Network). The results showed that several sites where the features predicted in the detection model concurred with geochemical anomalies were mapped. Other sites with similar characteristics, but for which no geochemical data were available, were also revealed. These sites are taken as new potential targets for the presence of seeps and oil reservoirs. The research demonstrated the excellent potential of ASTER data and spectral-spatial methodologies for low-cost, onshore exploration of hydrocarbons in Brazil.

Sorption and desorption characteristics of cadmium by four different soils in northeast China

Four soils, phaeozem (PM), saline-alkali soil (SA), meadow albic bleached soil (MA) and dark brown forest soil (DB) from Northeast China were used to examine the sorption and desorption characteristics of Cd and pH influence on it. According to sorption experiment without pH control, the order of amount of absorbed Cd by soils was: SA>PM>DB>MA. The results from non-linear fitting method showed that Langmuir and Freundrich models were more adaptable than Temkin model in describing the sorption data. The maximum sorption amounts from Langmuir model were: PM>SA>MA>DB. Exponential equation for PM and SA and quadratic equation for MA and DB were suitable to fit the desorption data. The order of average desorption percentage was: MA>DB>PM>SA. The amounts of sorption by PM, DB and MA reached the maximum in pH 9.0, while sorption by SA was linearly increased in the experimental range of pH 3.3–11.4. In uniform pH, however, Cd sorption by SA was the minimum among four soils, which indicated that the more amounts of Cd absorbed by SA in isotherm sorption were ascribed to the higher soil pH. The higher sorption of Cd in PM resulted from the higher percentage of organic matter and clay components.

Structural Components of Humic Acids as Determined by Chemical Modifications and Carbon‐13 NMR, Pyrolysis‐, and Thermochemolysis‐Gas Chromatography/Mass Spectrometry

The chemical structure of humic acids (HAs) extracted from a grassland surface soil and peat were studied using bleaching (NaClO2 oxidation) and acid hydrolysis (6 M HCl) in combination with advanced analytical techniques: solid‐state 13C nuclear magnetic resonance (NMR), pyrolysis‐gas chromatography/mass spectrometry (GC/MS), and tetramethylammonium hydroxide (TMAH) thermochemolysis‐GC/MS. The purpose of the chemical treatments was to remove known structural fragments from the HA to study the building blocks and components of the macromolecule. Bleaching the peat HA resulted in an attack on the lignin structures leading to a significant reduction in the C‐substituted and O‐substituted aromatic C peaks (128 and 150 ppm) in the 13C NMR spectrum. However, the bleached soil HA still contained residual aromatic C, suggesting that part of its aromaticity had originated from aromatic structures resistant to bleaching, possibly black C (charcoal). The pyrolysates of the bleached HAs contained mainly alkanes and alkenes (C8 to C29), whereas TMAH thermochemolysis yielded a homologous series of long‐chain fatty acid methyl esters (FAMEs) (C8 to C32) and dicarboxylic acid dimethyl esters (DAMES). The data are comparable with those obtained from pyrolysis and thermochemolysis of plant cuticular materials, and therefore suggest that cuticular residues are an integral part of the HA macromolecule. The acid hydrolysis treatment removed esters, amides, carbohydrates, and some of the N‐containing compounds from the HAs. This study demonstrates the effectiveness of bleaching and hydrolysis treatments together with advanced analytical techniques for characterization of aliphatic, lignin‐derived (LG) and nonhydrolyzable N‐containing structures associated with the HA macromolecule.

Early stages of podzolization under Corsican pine ( Pinus nigra Arn. ssp. laricio)

To assess the effects of the plants on pedogenesis, two arboreal species, Corsican pine ( Pinus nigra Arn. ssp. laricio) and silver fir ( Abies alba Mill.) were compared. We observed that at the base of the largest Corsican pines, patches of bleached soil occur on top of the A horizon. These eluviated areas lie at the outlet of wide bark channels through which the stemflow reaches the ground. In addition, an apparently less bleached material, in the shape of collars, is present around the big roots that collect and conduct the stemflow into the soil. On the contrary, patches and collars are absent in the soil under firs. To understand the role of the two species in the formation of the bleached material, throughfall, stemflow and forest floor solutions were collected for pine and fir. For pine, the stemflow moving along a wide bark channel was collected separately. All these solutions plus the rainfall were obtained and analysed seasonally for 1 year. Also, a number of profiles were excavated in the vicinity of the trunk base of pines and firs. Two profiles were selected for sampling and for the attendant analyses. The results indicate that under silver fir, the processes induce in the formation of an A horizon. The Corsican pine, on the other hand, in 50 years, has been able to produce, even if in small areas, a separate pedogenic process responsible for the bleaching of an existing A horizon. Because the bleaching process is at an initial stage, the chemical differences between the E material and the surrounding A horizon are small. Nevertheless, the E material is poorer in organic matter and in the most mobile inorganic elements than the A horizon. The presence of E material exclusively at the trunk base of the pines is due to the strong acidity of the stemflow — about 30-times higher than that of the fir. The most evident differences between the soils under pine and fir concern the features more directly related to the dynamics of the soil organic matter. Mineral assemblage, which needs longer time for its evolution, is very similar in the two soils; nonetheless a small amount of pedogenic smectite has been recognized in the E material.

The ecology of a beech forest on Mt. Sanpoiwadake, Hakusan National Park, Japan II. The correlation of the subassociation within the Lindero membranaceae‐fagetum crenatae association and environmental parameters

AbstractDetailed examination of a sample plot covered by the Lindero membranaceae‐Fagetum crenatae association on Mt. Sanpoiwadake, Hakusan National Park, revealed a number of correlations between the distribution of subassociations and environmental factors.The subassociations on the south‐facing slopes receive deep snow cover in winter with rapid melting in the spring. They occur on porous, freely draining soils, typical of the general range of brown forest soils. Conversely, on the north‐eastern slopes there are widespread late‐snow patches which delay leaf development and expansion and which provide an abundant water supply well into early summer. Under these conditions, bleached soil horizons have developed with iron pan formation, resulting in poor soil drainage, strongly correlated with quite different plant communities.

Introduction à une géographie des sols de la France du Nord-Est et de l'Europe rhénane

Abstract. Four great pedological provinces are distinguished in the North-East of France and Rhenish Germany. The brown soils are developed on the liasic and triasic regions of the « Plateau Lorrain ». The calcareous landscapes are characterised by red rendzinas, inherited from tertiary alterations and recarbonated in the periglacial times. In the hercynian mountains, the bad decomposition of the organic matter produces brown acid soils or sometimes podzolic soils, when rocks and expositions are favourable. In the Rhenish rift, the variety of soils is very great : the loess bears generally brown and brown bleached soils, but locally near Mainz a chernozem inherited from the Boreal period. The author attempts to give a chronology of this soils : the most evolved are dated from Boreal, Atlantic (brown soils) or Subboreal (heath-podzols).