Prediction of the Concentration of Solutes in Soil Solutions For Soil Systems Containing Gypsum and Exchangeable Ca and Mg

Potassium deficiency in grapes, as well as in other fruit crops grown on soils in the Niagara peninsula, is a common and often serious problem. Ap horizon samples from 12 of these soils and grape petiole samples from nine of the soil locations were analyzed to elucidate the behavior of the soil K and its availability to grapes. The soils ranged in texture from sandy loam to silty clay and their clay mineralogy was relatively uniform with mica as the main layer silicate. Vermiculite was quantified by potential K fixation methods and was concentrated in the clay. Up to 5.8% vermiculite was present in the soils which seemed to be sufficient to reduce K availability by K fixation. Amounts of exchangeable K extracted with NaCl or NH4Cl were relatively high (0.46–2.09 meq/100 g) but were not correlated with K uptake by grapes. Energies of K exchange obtained from immiscibly displaced soil solutions were closely related to vermiculite contents and amounts of K fixed after air drying. Energies of K exchange and ratios of exchangeable K over exchangeable Ca + Mg were highly correlated with K uptake by grapes. Soils with energies of K exchange less than or equal to −2800 cal/equiv. or K exch./(Ca + Mg) exch. equal to or more than 7% appeared to have adequate amounts of available K for grapes. These two analyses therefore show promise for predicting K availability to grapes. Key words: Exchangeability of K, energy of K exchange, fixation of K, soil mineralogy, availability of K to grapes

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The osmotic potential of soil water in plant/soil systems

Soil Research ◽

10.1071/sr9800013 ◽

1980 ◽

Vol 18 (1) ◽

pp. 13 ◽

Cited By ~ 5

Author(s):

R Sands ◽

CPP Reid

Keyword(s):

Soil Water ◽

Soil Solution ◽

Osmotic Potential ◽

Radiata Pine ◽

Plant Soil ◽

Total Potential ◽

Soil Systems ◽

Soil Solutions ◽

Soil Osmotic Potential ◽

Water Contents

Various techniques for measuring the osmotic potential of water in sand and loam at a range of soil water contents were examined. Results were inconsistent and variable when osmotic potential was derived by subtracting matric potential from total potential. Osmotic potential measurements on soil solution extruded at pressure through membranes were also unsatisfactory, probably due to salt sieving in the soil and/or at the membrane. Determining osmotic potential by linear dilution of an extract of 0.5 g g-1 soil solution can be criticized on several grounds, though the results presented for these soils seemed reasonable. The measurement of osmotic potential with in situ salinity sensors worked well in the loam but not in the sand. Measurements of the osmotic potential of displaced soil solutions were satisfactory for both soils. We concluded that the displacement technique was the most suitable for calibrating soil osmotic potential against soil water content, because it was simple, inexpensive in materials and time, and probably the least subject to error. The osmotic potential of soil dried by evaporation alone through a range of water contents was the same as that of soil dried by transpiration via lupins at two transpiration rates and via radiata pine. We concluded that the osmotic potential of the bulk soil in closed pots was independent of the activity of plants over the time scale of these experiments.

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Chemical attributes of some Queensland acid aoils. I. Solid and solution phase compositions

Soil Research ◽

10.1071/sr9890333 ◽

1989 ◽

Vol 27 (2) ◽

pp. 333 ◽

Cited By ~ 21

Author(s):

RC Bruce ◽

LA Warrell ◽

LC Bell ◽

DG Edwards

Keyword(s):

Acid Soils ◽

Logarithmic Scale ◽

Solution Ph ◽

Surface Soils ◽

Organic C ◽

Mean Values ◽

Exchangeable Ca ◽

Soil Solutions ◽

Chemical Attributes ◽

Linear Correlations

Samples from surface and subsoil horizons of 91 acid soils in Queensland were analysed for pH, EC, Cl, exchangeable cations and organic C. Generally low values for EC, Cl, exchangeable Na and exchangeable K were found in surface soils and subsoils. Higher values of organic C, exchangeable Ca and pH occurred more frequently in surface soils, while exchangeable A1 and exchangeable Mg were generally higher in subsoils. A correlation matrix gave significant, but not strong, linear correlations between soil attributes associated with soil acidity (pH and Ca, Mg and Al saturations). Soil solutions were extracted from surface and subsoil horizons of 48 of these acid soils and analysed for pH, EC, Na, K, Ca, Mg, SO4 and monomeric Al. Ionic strengths and activities of monomeric Al species were calculated. Soil solution pH tended to be lower in subsoils than in surface soils, but very few values were <4.5. Ionic strengths were mostly <8 mM, with mean values of 5.3 mM for surface soils and 2.4 mM for subsoils. Subsoils had lower mean concentrations of Ca, Mg and K, and similar concentrations of Na, compared with surface soils. In both groups, molar concentrations followed the order Na > K ~ Mg > Ca. Mean values for activities of AlOH2+, Al(OH)2+, Al(OH)3 and AlSO4+ in surface soils exceeded those for subsoils, but activities of Al3+ were similar. Higher activities of Al species in surface soils resulted from higher monomeric Al concentrations, but it was concluded that the analytical method overestimated monomeric Al in surface soils, probably by including some of the soluble organic Al complexes present. The best correlation between pH and Al species was with Al3+ , particularly in subsoils (r2 = 0.913). Activity of Al3+ in subsoils was correlated with ionic strength (r2 = 0.666) when both were expressed on a logarithmic scale.

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Dynamic Response of Reinforced Soil Systems. Phase 2.

10.21236/ada288740 ◽

1993 ◽

Author(s):

Kara L. Olen ◽

Richard J. Fragaszy ◽

Michael R. Purcell ◽

Kenneth W. Cargill

Keyword(s):

Dynamic Response ◽

Reinforced Soil ◽

Phase 2 ◽

Soil Systems

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Modeling Plant and Soil Systems

10.2134/agronmonogr31 ◽

1991 ◽

Cited By ~ 30

Keyword(s):

Soil Systems

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Reed bed treatment systems for sewage treatment in the United Kingdom - the first 10 years’ experience

Water Science & Technology ◽

10.2166/wst.1995.0154 ◽

1995 ◽

Vol 32 (3) ◽

pp. 317-327 ◽

Cited By ~ 12

Author(s):

P. Cooper ◽

B. Green

Keyword(s):

Root Zone ◽

Sewage Treatment ◽

Horizontal Flow ◽

Water Industry ◽

Soil Systems ◽

Design Changes ◽

Flow Systems ◽

Group A ◽

Reed Bed ◽

The Uk

The UK Water Industry first became interested in Reed Bed Treatment Systems for sewage in 1985. Early problems were experienced with soil-based horizontal-flow systems of the Root Zone type. The problems were overcome by national co-ordination of a development programme and international co-operation by an EC Expert Contact Group. A number of different types of systems have now been developed and the systems are now being accepted. The paper reviews the development of these systems for secondary and tertiary treatment and nitrification and mentions development of systems for other forms of treatment. The design changes made to overcome the problems are described. These include the gradual move to the use of gravel-based systems because of the difficulty experienced with over-land flow in the soil systems. The sizing of the systems is described together with performance data for the original horizontal-flow and the more recently developed vertical-flow systems. Treatment at secondary and tertiary levels is illustrated and the potential for nitrification. Early problems with reed growth have been overcome by planting with port-grown seedlings. After 10 years the process is generally accepted by the Water Industry as an appropriate treatment for villages and there are now between 200 and 300 systems in operation.

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Iron-Oxidizing Bacteria Are Associated with Ferric Hydroxide Precipitates (Fe-Plaque) on the Roots of Wetland Plants

Applied and Environmental Microbiology ◽

10.1128/aem.65.6.2758-2761.1999 ◽

1999 ◽

Vol 65 (6) ◽

pp. 2758-2761 ◽

Cited By ~ 174

Author(s):

David Emerson ◽

Johanna V. Weiss ◽

J. Patrick Megonigal

Keyword(s):

Ferric Hydroxide ◽

Root Systems ◽

Wetland Plants ◽

Positive Correlation ◽

Cell Numbers ◽

Iron Oxidizing Bacteria ◽

Soil Solutions ◽

Fe Plaque ◽

Ph Range

ABSTRACT The presence of Fe-oxidizing bacteria in the rhizosphere of four different species of wetland plants was investigated in a diverse wetland environment that had Fe(II) concentrations ranging from tens to hundreds of micromoles per liter and a pH range of 3.5 to 6.8. Enrichments for neutrophilic, putatively lithotrophic Fe-oxidizing bacteria were successful on roots from all four species; acidophilic Fe-oxidizing bacteria were enriched only on roots from plants whose root systems were exposed to soil solutions with a pH of <4. InSagittaria australis there was a positive correlation (P < 0.01) between cell numbers and the total amount of Fe present; the same correlation was not found for Leersia oryzoides. These results present the first evidence for culturable Fe-oxidizing bacteria associated with Fe-plaque in the rhizosphere.

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The Role of Biochar in Regulating the Carbon, Phosphorus, and Nitrogen Cycles Exemplified by Soil Systems

Sustainability ◽

10.3390/su13105612 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5612

Author(s):

Shu-Yuan Pan ◽

Cheng-Di Dong ◽

Jenn-Feng Su ◽

Po-Yen Wang ◽

Chiu-Wen Chen ◽

...

Keyword(s):

Environmental Sustainability ◽

Soil Amendment ◽

Environmental Control ◽

Current Knowledge ◽

Soil Environment ◽

Nitrogen And Phosphorus ◽

Soil Systems ◽

P Mineralization ◽

Rich Material ◽

Pyrolysis Of Biomass

Biochar is a carbon-rich material prepared from the pyrolysis of biomass under various conditions. Recently, biochar drew great attention due to its promising potential in climate change mitigation, soil amendment, and environmental control. Obviously, biochar can be a beneficial soil amendment in several ways including preventing nutrients loss due to leaching, increasing N and P mineralization, and enabling the microbial mediation of N2O and CO2 emissions. However, there are also conflicting reports on biochar effects, such as water logging and weathering induced change of surface properties that ultimately affects microbial growth and soil fertility. Despite the voluminous reports on soil and biochar properties, few studies have systematically addressed the effects of biochar on the sequestration of carbon, nitrogen, and phosphorus in soils. Information on microbially-mediated transformation of carbon (C), nitrogen (N), and phosphorus (P) species in the soil environment remains relatively uncertain. A systematic documentation of how biochar influences the fate and transport of carbon, phosphorus, and nitrogen in soil is crucial to promoting biochar applications toward environmental sustainability. This report first provides an overview on the adsorption of carbon, phosphorus, and nitrogen species on biochar, particularly in soil systems. Then, the biochar-mediated transformation of organic species, and the transport of carbon, nitrogen, and phosphorus in soil systems are discussed. This review also reports on the weathering process of biochar and implications in the soil environment. Lastly, the current knowledge gaps and priority research directions for the biochar-amended systems in the future are assessed. This review focuses on literatures published in the past decade (2009–2021) on the adsorption, degradation, transport, weathering, and transformation of C, N, and P species in soil systems with respect to biochar applications.

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Sacrificial Dissolution of Zinc Electroplated and Cold Galvanized Coated Steel in Saline and Soil Environments: A Comparison

Materials ◽

10.3390/ma14040744 ◽

2021 ◽

Vol 14 (4) ◽

pp. 744

Author(s):

Ameeq Farooq ◽

Umer Masood Chaudry ◽

Ahsan Saleem ◽

Kashif Mairaj Deen ◽

Kotiba Hamad ◽

...

Keyword(s):

Corrosion Rate ◽

Electrochemical Impedance ◽

Saline Soil ◽

Steel Substrate ◽

Salt Spray ◽

Steel Structures ◽

Open Circuit ◽

Cyclic Polarization ◽

Transfer Resistance ◽

Soil Solutions

To protect steel structures, zinc coatings are mostly used as a sacrificial barrier. This research aims to estimate the dissolution tendency of the electroplated and zinc-rich cold galvanized (ZRCG) coatings of a controlled thickness (35 ± 1 μm) applied via brush and dip coating methods on the mild steel. To assess the corrosion behavior of these coated samples in 3.5% NaCl and 10% NaCl containing soil solutions, open circuit potential (OCP), cyclic polarization (CP), and electrochemical impedance spectroscopy (EIS) tests were performed. The more negative OCP and appreciably large corrosion rate of the electroplated and ZRCG coated samples in 3.5% NaCl solution highlighted the preferential dissolution of Zn coatings. However, in saline soil solution, the relatively positive OCP (>−850 mV vs. Cu/CuSO4) and lower corrosion rate of the electroplated and ZRCG coatings compared to the uncoated steel sample indicated their incapacity to protect the steel substrate. The CP scans of the zinc electroplated samples showed a positive hysteresis loop after 24 h of exposure in 3.5% NaCl and saline soil solutions attributing to the localized dissolution of the coating. Similarly, the appreciable decrease in the charge transfer resistance of the electroplated samples after 24 h of exposure corresponded to their accelerated dissolution. Compared to the localized dissolution of the electroplated and brush-coated samples, the dip-coated ZRCG samples exhibited uniform dissolution during the extended exposure (500 h) salt spray test.

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Retention of the Antibiotic Cefuroxime onto Agricultural and Forest Soils

Applied Sciences ◽

10.3390/app11104663 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4663

Author(s):

Raquel Cela-Dablanca ◽

Carolina Nebot ◽

Lucia Rodríguez López ◽

David Ferández-Calviño ◽

Manuel Arias-Estévez ◽

...

Keyword(s):

Forest Soils ◽

Linear Models ◽

Agricultural Soils ◽

Organic Matter Content ◽

Matter Content ◽

Batch Type ◽

Exchangeable Ca ◽

Influence Of Ph ◽

Best Fit ◽

Soil Colloids

Antibiotics in wastewater, sewage sludge, manures, and slurries constitute a risk for the environment when spread on soils. This work studies the adsorption and desorption of the antibiotic cefuroxime (CFX) in 23 agricultural and forest soils, using batch-type experiments. Our results show that the adsorption values were between 40.75 and 99.57% in the agricultural soils, while the range was lower (from 74.57 to 93.46%) in forest soils. Among the Freundlich, Langmuir, and Linear models, the Freundlich equation shows the best fit for the adsorption results. In addition, agricultural soils with higher pH are the ones that present the highest adsorption. Further confirmation of the influence of pH on adsorption is given by the fact that Freundlich’s KF parameter and the Linear model Kd parameter shows a positive correlation with pH and with the exchangeable Ca and Mg values, which are known to affect the charges of the soil colloids and the formation of cationic bridges between adsorbents and adsorbate. In addition, Freundlich’s n parameter shows a positive and significant correlation with the organic matter content, related to the high adsorption taking place on forest soils despite their pH < 5. Regarding desorption, in most cases, it is lower than 1%, which indicates that CFX is adsorbed in a rather irreversible way onto these soils. Overall, these results can be considered relevant regarding their potential impact on environmental quality and public health.

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