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Humic acids isolated from six different Slovak soils have been characterized comparatively by using chemical methods and spectroscopic techniques including ultraviolet-visible (UV-VIS), 13 C nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR), fluorescence, and electron spin resonance (ESR). Results from elemental and functional group analyses and spectroscopic data...
Chemical fractionation and 31 P nuclear magnetic resonance (NMR) spectroscopy of humic acids (HA) and fulvic acids (FA) were used to characterize the forms of phosphorus and their changes within a toposequence of alpine soils at the Mt. Malaya Khatipara (Teberda reserve, northwestern Caucasus). Sodium hydroxide extracted 66-82% of total phosphorus from A horizons and 28-51% from B horizons...
Humic acids (HAs) extracted from the surface horizons of some Venezuelan soils were characterized by elemental and functional group analyses and visible, Fourier transform infrared (FT-IR), fluorescence and electron spin resonance (ESR) spectroscopies. The elementary composition of Venezuelan HAs was generally similar to that of HAs of temperate soils but carbon content was lower and oxygen content...
The humic substances (HS) of two Brazilian Oxisols, one under native grassland (NG) and the other submitted to a long-term (19-year) tillage systems experiment including no-tillage (NT), minimal tillage (MT) and an adjacent eucalyptus-planted forest (F), were extracted with sodium pyrophosphate, analysed and fractionated by exclusion chromatography on controlled pore glass (CPG). Chromatographic analysis...
The distribution of soil organic substances at five topographic sites was evaluated in the undisturbed mountainous forest of the Yuanyang lake ecosystem, northeastern Taiwan. The high annual rainfall there (>4000 mm) contributes to extreme acidity of the soil, which has a thick organic layer. The soil organic substances are classified as water soluble organic carbon (WSOC), microbial biomass carbon...
Chemical characteristics of highly humified humic acids (Type A HAs) from the subsoil of paddy fields (paddy soil HAs) and from the surface layer of ando soils (ando soil HAs) were compared based on the analyses of elemental composition, molecular size distribution, and 13 C CPMAS NMR spectra. Humic acids were extracted successively with 0.1 M NaOH and 0.1 M Na 4 P 2 O...
Humic acids (HAs) were isolated from the first generation of the EUROSOILS, a reference set of five samples representing the most widespread soil units in the European Union (EU). The EUROSOIL (E)-HA were characterized for their compositional, structural, and functional properties by using chemical methods and spectroscopic techniques, including Fourier transform infrared (FT IR), nuclear magnetic...
The influence of lead ions on the free radical concentration and the structure of humic acids isolated from soil, peat and compost was investigated by electron paramagnetic resonance (EPR), 13 C cross-polarization magic angle spinning nuclear magnetic resonance ( 13 C CP MAS NMR), Fourier transform infrared spectroscopy (FTIR) and chemical methods. A new type radical is formed...
Texture, among several other factors, may play an important role in controlling the distribution and activity of soil microbial biomass and, in turn, the size and quality of soil organic matter (SOM) pools, and the related dynamics of N and S in soil. Little information is available in the current literature on the occurrence and extent of these textural effects in semiarid soils of Argentinean Pampas...
Total luminescence spectroscopy (TLS) is a powerful novel technique for characterizing humified fractions of soil organic matter, and especially the humic acid (HA) fraction. Complexation reactions involving HAs play a key role in the speciation of Cu(II) ions in soil and, therefore, in controlling its biological availability, accumulation and mobility. In this study, HAs isolated from the first generation...
The potential for using commercially available potassium humate (K-humate) derived from Victorian Brown Coal to improve soil structure and aggregate stability was assessed in this study. Laboratory experiments were conducted on two agricultural soils from the southeastern and northern parts of Victoria, Australia. Bulk surface soil (0–15 cm) samples of an acidic soil (pH 4.6) from Dixons Creek in...
Forty two samples of black soils were collected from superficial horizons of the High Altitude Rocky Complex (HARC) that is situated on top of the most prominent mountain ranges of eastern Brazil. Our objective was to characterize the humic acids extracted from these pedoenvironments and evaluate the effect of natural paleo-fires on thermogravimetric properties, elemental composition, visible and...
Base- and acid-hydrolysable fractions of humic acids (HAs) isolated from a forest soil, an agricultural soil and a lignite deposit were analysed, and comparisons were made between the base hydrolysable lipid (bound lipid), carbohydrate and amino acid signatures of the different humic acids.Bound lipids differ depending on the humic acid origin. Their composition were rather similar for the two soil...
Humic acids (HA) from soils of very different origin and bioclimatic conditions (podzoluvisol, phasozem, chernozem, and ferralsol) were fractionated by coupling size-exclusion chromatography and polyacrylamide gel electrophoresis (tandem SEC–PAGE). From each HA, three fractions—A, B, and C+D, with different molecular sizes and electrophoretic mobilities—were obtained and analysed by thermochemolysis,...
Laser-induced fluorescence (LIF) spectroscopy has been proposed as new method for determining the degree of humification of organic matter (OM) in whole soils. It can be also used to analyze the OM in whole soils containing large amounts of paramagnetic materials, and which are neither feasible to Electron Paramagnetic Resonance (EPR) nor to 13 C Nuclear Magnetic Resonance (NMR) spectroscopy...
The objective of this study was to characterise the composition, structure and functionalities of humic acids (HAs) isolated from hydromorphic sandy soils of the upper Negro river basin, Amazonas, Brazil, in order to obtain information on organic matter dynamics in these tropical forest ecosystems. For this purpose, three soil layers, i.e., the superficial earthworm casts, the A horizon and the Bh...
An ombrotrophic peat core (10×10×81 cm) was collected from Etang de la Gruère (Switzerland) and divided in 27 slices of 3 cm. Humic acids (HAs) were extracted from each slice after freeze-drying and fine milling. All raw peat and HA samples were analyzed using Energy-dispersive miniprobe X-ray fluorescence multielement analyser (EMMA-XRF), fluorescence spectroscopy and Low Background γ-spectrometry...
Composting and vermicomposting processes are useful methods for producing a stabilized and mature organic material; rich in humic substances, which may change some properties in the soil solution.Through both processes the final products are stabilized and mature organic matter, rich in humic acids (HA), which are the main and more stable component of the organic matter, and contribute to the essential...
Scientific results about the role of peatlands as sink or source of bromine are rather antithetic. Although several attempts have been performed to correlate Br content and peat decomposition/humification, the role of humic acids (HAs) as possible sink of this element has not been previously investigated. Two peat cores (2H and 2T), collected from the ombrotrophic bog Etang de la Gruère (Switzerland),...
In this study a typical grey-brown podzolic soil was amended with different doses of a brown coal-based preparation called Rekulter (R) largely used in Poland. After seven years, soils were analyzed and humic acids (HAs) were extracted both from the control soil and from the amended soils. All HAs were characterized by Fourier transform infrared spectroscopy and fluorescence spectroscopy both in emission,...
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