Retention and plant availability of chromium in soils as affected by lime and organic matter amendments

Chromium is used as Cr(III) in the tannery industry and as Cr(VI) in the timber treatment industry. In this experiment, the effect of 2 liming materials [fluidised bed boiler ash (FBA) and lime] and an organic amendment (Pinus radiata bark) on the retention of Cr by 2 soils (Egmont and Tokomaru) was examined using both ‘batch’ and ‘column’ experiments. The effect of these amendments on the uptake of Cr from the Egmont soil, treated with various levels of Cr (0–3200 mg Cr/kg soil), was examined using sunflower (Helianthus annuus) plants. The transformation of Cr was examined by fractionation of Cr in soils. Addition of FBA and lime increased the retention of Cr(III), but had the opposite effect on the retention of Cr(VI). Addition of bark did not affect the retention of Cr(III), but it increased the retention of Cr(VI). Increasing additions of Cr increased Cr concentration in plants, resulting in decreased plant growth. The liming materials were found to be effective in reducing the phytotoxicity of Cr(III) and the Pinus radiata bark was effective for Cr(VI). In both Cr(III)- and Cr(VI)-contaminated soils, the concentrations of Cr were higher in the organic-bound, oxide-bound, and residual fractions than in the soluble and the exchangeable fractions. The concentrations of Cr in the soluble and the exchangeable fractions were higher in the Cr(VI)-contaminated than the Cr(III)-contaminated soil. Addition of the liming materials decreased the concentration of the soluble Cr(III) and bark decreased soluble Cr(VI) in soil. There was evidence for the reduction of Cr(VI) to Cr(III) in the bark-treated soils.

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Fractionation of Heavy Metals in Multi-Contaminated Soil Treated with Biochar Using the Sequential Extraction Procedure

Biomolecules ◽

10.3390/biom11030448 ◽

2021 ◽

Vol 11 (3) ◽

pp. 448

Author(s):

Mahrous Awad ◽

Zhongzhen Liu ◽

Milan Skalicky ◽

Eldessoky S. Dessoky ◽

Marian Brestic ◽

...

Keyword(s):

Heavy Metals ◽

Organic Matter ◽

Soil Organic Matter ◽

Soil Ph ◽

Contaminated Soil ◽

Contaminated Soils ◽

Extraction Procedure ◽

Sequential Fractionation ◽

Relationship Of ◽

The Relationship

Heavy metals (HMs) toxicity represents a global problem depending on the soil environment’s geochemical forms. Biochar addition safely reduces HMs mobile forms, thus, reducing their toxicity to plants. While several studies have shown that biochar could significantly stabilize HMs in contaminated soils, the study of the relationship of soil properties to potential mechanisms still needs further clarification; hence the importance of assessing a naturally contaminated soil amended, in this case with Paulownia biochar (PB) and Bamboo biochar (BB) to fractionate Pb, Cd, Zn, and Cu using short sequential fractionation plans. The relationship of soil pH and organic matter and its effect on the redistribution of these metals were estimated. The results indicated that the acid-soluble metals decreased while the fraction bound to organic matter increased compared to untreated pots. The increase in the organic matter metal-bound was mostly at the expense of the decrease in the acid extractable and Fe/Mn bound ones. The highest application of PB increased the organically bound fraction of Pb, Cd, Zn, and Cu (62, 61, 34, and 61%, respectively), while the BB increased them (61, 49, 42, and 22%, respectively) over the control. Meanwhile, Fe/Mn oxides bound represents the large portion associated with zinc and copper. Concerning soil organic matter (SOM) and soil pH, as potential tools to reduce the risk of the target metals, a significant positive correlation was observed with acid-soluble extractable metal, while a negative correlation was obtained with organic matter-bound metal. The principal component analysis (PCA) shows that the total variance represents 89.7% for the TCPL-extractable and HMs forms and their relation to pH and SOM, which confirms the positive effect of the pH and SOM under PB and BB treatments on reducing the risk of the studied metals. The mobility and bioavailability of these metals and their geochemical forms widely varied according to pH, soil organic matter, biochar types, and application rates. As an environmentally friendly and economical material, biochar emphasizes its importance as a tool that makes the soil more suitable for safe cultivation in the short term and its long-term sustainability. This study proves that it reduces the mobility of HMs, their environmental risks and contributes to food safety. It also confirms that performing more controlled experiments, such as a pot, is a disciplined and effective way to assess the suitability of different types of biochar as soil modifications to restore HMs contaminated soil via controlling the mobilization of these minerals.

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Soil organic matter–hydrogen peroxide dynamics in the treatment of contaminated soils and groundwater using catalyzed H2O2 propagations (modified Fenton's reagent)

Water Research ◽

10.1016/j.watres.2006.05.009 ◽

2006 ◽

Vol 40 (13) ◽

pp. 2477-2484 ◽

Cited By ~ 81

Author(s):

L BISSEY ◽

J SMITH ◽

R WATTS

Keyword(s):

Hydrogen Peroxide ◽

Organic Matter ◽

Soil Organic Matter ◽

Contaminated Soils ◽

Fenton’S Reagent ◽

Fenton's Reagent

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The interactive effect of an AM fungus and an organic amendment with regard to improving inoculum potential and the growth and nutrition of Trifolium repens in Cd-contaminated soils

Applied Soil Ecology ◽

10.1016/j.apsoil.2009.12.004 ◽

2010 ◽

Vol 44 (2) ◽

pp. 181-189 ◽

Cited By ~ 12

Author(s):

A. Medina ◽

N. Vassilev ◽

R. Azcón

Keyword(s):

Trifolium Repens ◽

Contaminated Soils ◽

Organic Amendment ◽

Interactive Effect ◽

Inoculum Potential ◽

Growth And Nutrition ◽

Am Fungus

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Above and Belowground Growth of Corymbia maculata in a Constructed Soil: The Effect of Profile Design and Organic Amendment

Arboriculture & Urban Forestry ◽

10.48044/jauf.2010.002 ◽

2010 ◽

Vol 36 (1) ◽

pp. 11-17

Author(s):

Karen Smith ◽

Peter May ◽

Robert White

Keyword(s):

Organic Matter ◽

Root Length ◽

Organic Amendment ◽

Root Length Density ◽

Dry Weight ◽

Nutrient Status ◽

Fertilizer Treatment ◽

Coir Fiber ◽

Growth Responses ◽

Profile Design

Spotted gum (Corymbia maculata (Hook.) K.D. Hill & L.A.S. Johnson), a common street tree in southern Australian cities, was used to assess growth responses to variations in profile design and organic amendment of constructed soils. Aboveground growth responses were total stem dry weight and foliar nutrient content. The belowground response was root length density. Soil profiles were constructed of sand, amended with either coir fiber, composted biosolids or composted green waste, at rates of 0, 5, 10 or 20% by volume. The profiles were either layered, with a 150 mm (6 in) organic-amended surface layer, or uniform, with amendment of the entire profile. A single fertilizer treatment was applied to all profiles. Shoot dry weight was only affected by organic matter type with the greatest growth in sand amended with composted biosolids. Foliage P and K content were affected by amendment but foliage N was not. Profile design affected root length density and distribution. Trees in uniform profiles had greater root length density, and a more uniform distribution of roots, especially with compost amendments. Above- and belowground growth increases are thought to be due to increased nutrient status resulting from organic matter mineralization.

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Effect of pH on the adsorption of phosphate and potassium in batch and in column experiments

Soil Research ◽

10.1071/sr9880165 ◽

1988 ◽

Vol 26 (1) ◽

pp. 165 ◽

Cited By ~ 19

Author(s):

NS Bolan ◽

JK Syers ◽

RW Tillman

Keyword(s):

Soil Solution ◽

Opposite Effect ◽

Column Experiment ◽

Batch Experiment ◽

Column Experiments ◽

Effect Of Ph ◽

The Difference

The effect of increasing pH, through incubation with Ca(OH)2 and NaOH, on the adsorption of phosphate (P) and potassium (K) was examined in batch and in column experiments. In column experiments, an increase in pH from 5.2 to 8.2 decreased the adsorption of P and increased that of K which resulted in an increased leaching of P and a decreased leaching of K. In a batch experiment, however, an increase in pH resulting from incubation with NaOH gave similar results to those of the column experiment, whereas an increase in pH due to Ca(OH)2 addition caused the opposite effect on the adsorption of both P and K. The difference between the batch and the column experiments in the effect of incubating soil with Ca(OH)2 on the adsorption of P and K is related to the concentration of Ca in the soil solution.

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Relationship of soil properties to fractionation, bioavailability and mobility of lead and zinc in soil

Plant Soil and Environment ◽

10.17221/2201-pse ◽

2008 ◽

Vol 53 (No. 5) ◽

pp. 225-238 ◽

Cited By ~ 28

Author(s):

N. Finžgar ◽

P. Tlustoš ◽

D. Leštan

Keyword(s):

Organic Matter ◽

Regression Analysis ◽

Soil Organic Matter ◽

Soil Properties ◽

Multiple Regression ◽

Contaminated Soils ◽

Organic Matter Content ◽

Clay Content ◽

Exchange Capacity ◽

Matter Content

Sequential extractions, metal uptake by Taraxacum officinale, Ruby’s physiologically based extraction test (PBET) and toxicity characteristic leaching procedure (TCLP), were used to assess the risk of Pb and Zn in contaminated soils, and to determine relationships among soil characteristics, heavy metals soil fractionation, bioavailability and leachability. Regression analysis using linear and 2nd order polynomial models indicated relationships between Pb and Zn contamination and soil properties, although of small significance (P < 0.05). Statistically highly significant correlations (P < 0.001) were obtained using multiple regression analysis. A correlation between soil cation exchange capacity (CEC) and soil organic matter and clay content was expected. The proportion of Pb in the PBET intestinal phase correlated with total soil Pb and Pb bound to soil oxides and the organic matter fraction. The leachable Pb, extracted with TCLP, correlated with the Pb bound to carbonates and soil organic matter content (R2 = 69%). No highly significant correlations (P < 0.001) for Zn with soil properties or Zn fractionation were obtained using multiple regression.

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