Sorption characteristics of copper(II) in selected calcareous soils of Iran in relation to soil properties

2002 ◽  
Vol 33 (13-14) ◽  
pp. 2279-2289 ◽  
Author(s):  
M. Maftoun ◽  
N. Karimian ◽  
F. Moshiri
Keyword(s):  
Soil Properties ◽  
Calcareous Soils ◽  
Sorption Characteristics

scholarly journals Phosphorus Supply of Typical Hungarian Soils

2006 ◽  
Vol 55 (1) ◽  
pp. 117-126 ◽  
Author(s):  
György Füleky
Keyword(s):  
Soil Properties ◽  
Inorganic Phosphate ◽  
Phosphorus Uptake ◽  
Calcareous Soils ◽  
Hot Water ◽  
Percolation Method ◽  
Water Percolation ◽  
Phosphorus Source ◽  
Fraction I ◽  
Test Plants

The new hot water percolation (HWP) method was introduced to determine the phosphorus supply of soils from the Soil Bank of 36 Hungarian soils. The present work aimed to explain the availability of phosphorus by determining the inorganic phosphate fractions and using ryegrass test plants. Four inorganic phosphate fractions were distinguished: Fraction I, the sorbed phosphates; Fraction II, the easily soluble Ca phosphates and the Al bound phosphates; Fraction III, the Fe phosphates; and Fraction IV, the hardly soluble Ca phosphates. Fraction II, in which the easily soluble Ca phosphates and Al phosphates accumulate, was the main phosphorus source for the test plants on both calcareous and non-calcareous soils. Fraction III (the iron phosphates) plays a greater role in non-calcareous soils, while Fraction IV (the hardly soluble Ca phosphates) in calcareous soils. Both fractions are closely connected with soil development, and with soil properties such as pH and CaCO 3 content. The hot water percolation method reflects the phosphorus supply of soil as well as that measured with ryegrass plants and with the AL method. This new HWP method is in good correlation with the main source of phosphate, with fraction II. For routine purposes the first collected HWP fraction can possibly be used to determine the phosphorus supply of soil correlating well with the phosphorus uptake of test plants.

Relationship between soil composition and retention capacity of terbumeton onto chalky soils

2009 ◽  
Vol 6 (3) ◽  
pp. 245 ◽  
Author(s):  
Achouak El Arfaoui ◽  
Stéphanie Sayen ◽  
Eric Marceau ◽  
Lorenzo Stievano ◽  
Emmanuel Guillon ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Properties ◽  
Environmental Fate ◽  
Organic Matter Content ◽  
Calcareous Soils ◽  
Matter Content ◽  
Soil Composition ◽  
Retention Capacity ◽  
Wide Range ◽  
Soil Components

Environmental context. The wide use of pesticides for pest and weed control contributes to their presence in underground and surface waters, which has led to a continuously growing interest in their environmental fate. Soils play a key role in the transfer of these compounds from the sprayer to the water as a result of their capacity to retain pesticides depending on the soil components. The knowledge of soil composition should enable one to predict pesticide behaviour in the environment. Abstract. Eight calcareous soils of Champagne vineyards (France) were studied to investigate the adsorption of the herbicide terbumeton (TER). A preliminary characterisation of the soil samples using X-ray diffraction (XRD), elemental and textural analyses, revealed a wide range of soil properties for the selected samples. The adsorption isotherms of TER were plotted for all samples. The determination of soil properties, which significantly correlated with the Kd distribution coefficient, allowed identification of organic matter and CaCO3 as the two main soil components that govern the retention of the herbicide. Organic matter was the predominant phase involved in the retention but its role was limited by the presence of calcite. Finally, the ratio of CaCO3 content to organic matter content was proposed as a useful parameter to predict the adsorption of terbumeton in chalky soils. The evolution of Kd as a function of this ratio was successfully described using an empirical model.

Macropore-matrix mass transfer: reactive solute transport as quantified with Fluorescence imaging

2020 ◽  
Author(s):  
Christoph Haas ◽  
Ruth Ellerbrock ◽  
Horst H. Gerke
Keyword(s):  
Mass Transfer ◽  
Soil Properties ◽  
Fluorescence Imaging ◽  
Mass Exchange ◽  
Soil Structure ◽  
Transport Processes ◽  
Hydraulic Transport ◽  
Soil Matrix ◽  
Adsorption Sites ◽  
Sorption Characteristics

<p>Preferential flow paths in soils play a major role for transport processes of heat, gas, water, and solutes and are important adsorption sites. For mass-exchange processes and water storage in soils, small-scaled soil properties, like the spatial distribution of adsorption sites and their accessibility, and the permeability are crucial. Interfaces between macropores (i.e., earthworm burrows, cracks, and root channels) and the soil matrix control the mass exchange. Water and solute transfer through the interface between bio-pores, aggregate or crack surfaces and the matrix was traced at the scale of small soil blocks (≤45 mm edge length) with Fluorescein (i.e., a reactive, fluorescent dye). The objectives were to visualize and quantify hydraulic transport, and sorption characteristics of earthworm-, root- and shrinkage-induced interfaces. Batch experiments were performed to calibrate the Na-Fluorescein tracer concentration versus fluorescence-intensity relationship and to derive parameters for two kinetic sorption models (i.e., Freundlich vs. Langmuir). Fluorescence imaging in the laboratory of small soil blocks was applied with a self-constructed spraying device, and with the help of the calibration, small-scaled dye-concentration maps were derived. Time- and interface-dependent positions of the wetting fronts in vertical direction were estimated with the help of the cumulative infiltration. Assuming equilibrated conditions between Na-Fluorescein in solution (calculated by multiplying the locale dye-concentration and the local water content) and Na-Fluorescein sorbed to soil, the total mass transfers as a function of macropore-type and spraying time were determined. The results of the mass transfer for water and reactive solutes were characteristic for the soil structure type and depending on the composition of the macropore-matrix interface. Differences were explained by alterations in soil structure and chemical composition of the coatings. Results suggest relations between mass exchange and observable soil properties. This can be helpful for improving the numerical simulation of macropore-matrix mass transfer and inverse simulations of small-scaled hydraulic, transport, and sorption characteristics of macropore walls.</p>

scholarly journals Changes of Available Cadmium Over time and its Relationship with Soil Properties in Highly Calcareous Soils

2018 ◽  
Vol 22 (1) ◽  
pp. 127-142
Author(s):  
M. Hosseini ◽  
E. Adhami ◽  
H. R Owliaie ◽  
◽  
◽  
...  
Keyword(s):  
Soil Properties ◽  
Calcareous Soils ◽  
Over Time

Effects of decalcification on the phosphate sorption characteristics of eight calcareous soils

Soil Research ◽  
1990 ◽  
Vol 28 (6) ◽  
pp. 919 ◽  
Author(s):  
ICR Holford ◽  
M Chater ◽  
GEG Mattingly
Keyword(s):  
Calcareous Soils ◽  
Sorption Isotherms ◽  
Phosphate Sorption ◽  
Surface Equation ◽  
P Sorption ◽  
Surface Areas ◽  
Freundlich Equation ◽  
Sorption Parameters ◽  
Parameter Values ◽  
Sorption Characteristics

Phosphate sorption isotherms and parameter values were determined on eight calcareous soils which were carefully decalcified using a procedure which minimized changes in cation saturation. Calcite content of the original soils varied from 0.8 to 24 2% and calcite surface areas from 4 . 0 to 8.5 m2 g-1. Sorption parameters were derived from the Langmuir 'two-surface' equation. Decalcification increased phosphate sorption at low residual P concentrations (<0.8 mg L-1) but decreased it at higher concentrations. The higher P sorption was associated with an increase in affinity because the calculated sorption capacities of high-affinity surfaces were not increased. These sorption capacities were well correlated with iron oxide contents of the soils, so the increase in phosphate affinity of these surfaces was consistent with the decrease in pH (0.5 to 1.5 units) of the decalcified soils. The lower P sorption at higher concentrations was associated with a substantial decrease in sorption capacity of the postulated low-affinity surfaces. These latter decreases were quantitatively correlated with the calcite surface areas of the original soils. These and other changes in phosphate sorption characteristics support the utility of the Langmuir 'two-surface' equation in providing information, compatible with what would be expected from more complex mechanistic models, and which exceeds what one would expect from other simpler models such as the Freundlich equation. They also support an hypothesis that an important component of low-affinity surfaces of these calcareous soils is calcite on which organic anions are co-adsorbed.

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