Modelling the Plant Uptake of Metals from Release Rates Obtained by the EUF Method

In this study, soil dissolution kinetics were evaluated to predict the metal uptake of lettuce plants under varying conditions of fertilisation and metal pollution. Velocities and time dependencies of soil dissolution obtained by electro-ultrafiltration (EUF), which prevents back reaction, were modelled in three ways, obtained from suspensions in 0.002 M DTPA at determined soil pH levels, for cases in which sampling versus time led to decreasing concentrations. The models yielded a maximum achievable concentration, a timespan needed for it to be reached, a slope, and an intercept of the respective fitted curves. Three geogenically metalliferous soil samples and one ambient soil sample, both as originals, fertilised with PK or soaked with a Cd-Ni-Pb solution, were used as solid samples. The resulting kinetic parameters were correlated with the amounts absorbed by lettuce plants grown with these substrates in pot experiments, which yielded fairly good correlations with Zn, but also with Li and Sr, as well as Ni and Pb, mainly because of differences due to the addition of a metallic salt solution. Plant growth was hardly influenced by the additions.

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THE AVAILABILITY OF RESIDUAL FERTILIZER NITROGEN IMMOBILIZED AS CLAY-FIXED AMMONIUM AND ORGANIC N

Canadian Journal of Soil Science ◽

10.4141/cjss82-052 ◽

1982 ◽

Vol 62 (3) ◽

pp. 479-486 ◽

Cited By ~ 20

Author(s):

CAROLINE M. PRESTON

Keyword(s):

Plant Uptake ◽

Soil Samples ◽

Organic N ◽

N Availability ◽

Aqueous Extracts ◽

Fertilizer N ◽

Ammonium N ◽

Available Carbon ◽

The Relationship ◽

Residual Fertilizer N

A study of plant uptake, incubation-extraction and acid hydrolysis was carried out on soil samples from a field study using 15N. The samples had varying proportions of residual fertilizer 15N (15Nex) as clay-fixed ammonium and organic N. Availability of 15Nex to plants was positively correlated with percent of 15Nex as clay-fixed ammonium, and negatively correlated with percent of 15Nex as organic N. A similar relationship was noted for recovery of 15Nex in acid hydrolysates. The relationship was reversed for recovery of 15Nex in aqueous extracts following incubation, although this may have been due to lack of removal of N by plant uptake or leaching, and limitation of microbial activity by lack of readily available carbon. This direct comparison of availability of residual fertilizer N as clay-fixed ammonium N and organic N demonstrates that fertilizer N, once incorporated into organic forms, is much less available to plants than fertilizer N in the form of clay-fixed ammonium.

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Predicting availability of mineral elements to plants with the DGT technique: a review of experimental data and interpretation by modelling

Environmental Chemistry ◽

10.1071/en09010 ◽

2009 ◽

Vol 6 (3) ◽

pp. 198 ◽

Cited By ~ 157

Author(s):

Fien Degryse ◽

Erik Smolders ◽

Hao Zhang ◽

William Davison

Keyword(s):

Plant Uptake ◽

Metal Uptake ◽

Phosphorus Deficiency ◽

Mineral Elements ◽

Diffusive Transport ◽

Strong Correlations ◽

P Deficiency ◽

Diffusive Gradients ◽

Rate Limiting ◽

Theoretical Considerations

Environmental context. Total concentrations of mineral elements in soil bear little relation to their availability for plants. The DGT (diffusive gradients in thin-films) technique has been found to be a good predictor of trace metal uptake and P deficiency, though not consistently in all studies for all elements. This review examines the fundamental basis for the relation between DGT fluxes and plant uptake and assesses under which conditions this relation may break down. Abstract. In the DGT technique, elements are accumulated on a binding gel after their diffusive transport through a hydrogel. In this paper, we explore in more detail why – and under which conditions – DGT correlates with plant uptake. The theoretical considerations are illustrated with experimental results for metal uptake and toxicity, and for phosphorus deficiency. Strong correlations between DGT and plant uptake are predicted if the diffusive transport of the element from soil to the plant roots is rate-limiting for its uptake. If uptake is not limited by diffusive transport, DGT-fluxes and plant uptake may still correlate provided that plant uptake is not saturated. However, competitive cations may affect the plant uptake under these conditions, whereas they have no effect on the DGT flux. Moreover, labile complexes are not expected to contribute to the plant uptake if diffusion is not limiting, but they are measured with DGT. Therefore, if plant uptake is not limited by diffusion, interpretation of the observed correlation in terms of the labile species measured by DGT is inappropriate.

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Modelling plant uptake of Cd, Ni and Pb from mobile fractions and release rates obtained by the EUF-method

10.5194/egusphere-egu21-6283 ◽

2021 ◽

Author(s):

Manfred Sager ◽

Anto Jelecevic ◽

Peter Liebhard

Keyword(s):

Plant Uptake ◽

Metal Salt ◽

Food Contamination ◽

Mineral Fertilizers ◽

Release Rates ◽

High Accumulation ◽

Filtration Method ◽

Dependence Versus ◽

Ultra Filtration ◽

Cadmium And Lead

<p>In order to predict concentrations in green plants from kinetic data as well as from mobile soil fractions from geogenically enriched areas, soils from historic mining and smelting sites in Styria (Austria) were used to grow lettuce in pot experiments. Lettuce is known for high accumulation of Ni and Cd in the shoots as well, but in our case, uptakes remained low. Addition of a mixed metal salt solution resulted in high Ni concentrations in the plants, contrary to Cd and Pb. Effects of mineral fertilizers and metal salt additions upon plant metal uptake and N resp C/N shifts were monitored and combined with results from batch-extraction as well as with release rates and released amounts obtained by a modified EUF (electro-ultra-filtration) method.</p><p>The release obtained by EUF in 0,002M DTPA was modelled by linear, logarithmic, parabolic (&#8730;) and quadratic dependence versus time, from original as well as from cumulated datasets. As expected, addition of soluble salts increased the release, whereas addition of PK fertilizer lowered the release of the metals from soil. Thus, food contamination hazards can be lowered by adequate agricultural activities. Plant uptake by nickel got clearly enhanced by metal salt additions, whereas effects of added cadmium and lead were lower. Correlations between plant uptake and release rates resp. released amounts were in the same range, whatever model was used.</p>

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Experimental Determination of the Dissolution Kinetics of Plutonium- and Uranium-Bearing Ceramics at 90°C

MRS Proceedings ◽

10.1557/proc-713-jj11.38 ◽

2002 ◽

Vol 713 ◽

Cited By ~ 1

Author(s):

J. P. Icenhower ◽

B. P. McGrail ◽

D. M. Strachan ◽

R. D. Scheele ◽

V. L. Legore ◽

...

Keyword(s):

Radiation Damage ◽

Dissolution Kinetics ◽

Solution Rate ◽

Release Rates ◽

Solution Ph ◽

Bearing Materials ◽

Flow Through ◽

Effects Of Radiation ◽

Kinetics Of

ABSTRACTAs a first step toward understanding the effects of radiation damage on element release rates from Ti-bearing waste forms, we performed single-pass flow-through (SPFT) experiments with 239Pu- and 238U-bearing ceramics over a solution pH-interval of 2 to 10 at 90°C. The ceramics tested are chemically complex and are dominated volumetrically by betafite (Ti-pyrochlore) (ABTi2O7) (A = Ca2+, Gd3+, B = Gd3+, Hf4+, Pu4+, U4/6+). The 239Pu-bearing specimens contained 11.9 mass% PuO2 and 23.7 mass% UO2. In addition, a 238Pu-bearing (11.8 and 23.9 mass% PuO2 and UO2, respectively) specimen was tested at pH = 2, 90°C. The 239Pu-bearing specimens slowly released Pu to solution (rate = 7.6x10-6 g m-2 d-1), even at pH = 2. Release of elements across the pH interval investigated exhibits a weak amphoteric behavior. Compared to results from the 239Pu-bearing materials, the 238Pu-bearing specimen released Pu >1000X faster (rate = 9.3x10-3 g m-2 d-1) at pH = 2. Release rates of U, Gd, and Hf are also faster from the 238Pu-bearing ceramic compared to the specimen containing 239Pu. Although preliminary, the data can be interpreted to indicate that accumulation of radiation damage may result in faster release of Pu and U to solution than previously suspected.

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Sulfate sorption measured by a buffering index over a range of properties of soils from south Western Australia

Soil Research ◽

10.1071/sr20005 ◽

2020 ◽

Vol 58 (7) ◽

pp. 651 ◽

Cited By ~ 2

Author(s):

G. C. Anderson

Keyword(s):

Plant Uptake ◽

Soil Layer ◽

Equilibrium Concentration ◽

Sulfate Solution ◽

Soil Samples ◽

Freundlich Equation ◽

Soil Sulfur ◽

Sulfate Leaching ◽

Adsorption Curve ◽

Sorption Curve

Sulfate sorption by the soil affects the rate of sulfate leaching, which impacts on the availability of soil sulfate for plant uptake. In Australia, plant-available sulfur is measured using 0.25 M KCl heated for 3 h at 40°C to extract soil sulfur (SKCl40). This paper describes a technique referred to as a sulfate buffering index (SBI), which provides a measurement of sulfate sorption. SBI when combined with the estimates of the q and b parameters of the Freundlich equation, can be used to define a sorption curve. The equation is S = acb – q; where S is the amount of sulfate adsorbed (mg S kg–1), c is the equilibrium concentration of sulfate measured in solution (mg S L–1) and a, b and q are coefficients that describe the soil sulfate sorption curve. Coefficients S and c were measured using six sulfate solution concentrations ranging from 0 to 250 mg S kg–1. The adsorption curve was fitted using the modified Freundlich equation including setting of b = 0.41 and q = SKCl40 using recently collected soil samples. The modified Freundlich a coefficient or SBI was calculated as SBI = (S + SKCl40)/c0.41; where S and c were determined using 50 mg S kg–1 of added sulfate. The SBI ranged within 1–40. The SKCl40 was related to SBI below a depth of 10 cm (r2 = 0.71) but not for the 0–10 cm soil layer where S sorption was minimal.

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Chromium-Based Polypyrrole/MIL-101 Nanocomposite as an Effective Sorbent for Headspace Microextraction of Methyl tert-Butyl Ether in Soil Samples

Molecules ◽

10.3390/molecules25030644 ◽

2020 ◽

Vol 25 (3) ◽

pp. 644 ◽

Cited By ~ 3

Author(s):

Jila Darabi ◽

Alireza Ghiasvand

Keyword(s):

Limit Of Detection ◽

Solid Phase ◽

Soil Samples ◽

Methyl Tert Butyl Ether ◽

Infrared Spectrometry ◽

Extraction Temperature ◽

Solid Samples ◽

Butyl Ether ◽

Tert Butyl ◽

Relative Standard

The performance of headspace solid-phase microextraction (HS-SPME) was upgraded by easy and low-cost preparation of a new nanocomposite fiber. A polypyrrole/chromium-based metal–organic framework, PPy@MIL-101(Cr), nanocomposite was electrochemically synthesized and simultaneously coated on a steel wire as a microextraction sorbent. The morphology and chemical structure of the prepared nanocomposite was characterized by Fourier-transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) techniques. The microsorbent was used for sampling of methyl-tert-butyl ether (MTBE) in solid samples, through an HS-SPME sampling strategy, followed by GC-FID measurement. The optimal experimental conditions, including extraction temperature, extraction time, and GC desorption conditions, were evaluated and optimized. The proposed procedure showed good sensitivity (limit of detection was 0.01 ng·g−1) and precision (relative standard deviation was 8.4% for six replicated analyses). The calibration curve was linear over the range of 5–40,000 ng·g−1, with a correlation coefficient of 0.994. The limit of quantification was 0.4 ng·g−1. The fabricated fiber exhibited good repeatability and reproducibility for the sampling of MTBE, with average recovery values of 88–114%. The intra-fiber and inter-fiber precisions were found to be 8.4% and 19%, respectively. The results demonstrated the superiority of the PPy@MIL-101(Cr)-coated fiber in comparison with handmade (polypyrrole, PPY) and commercial fibers (polyacrylate, PA; polydimethylsiloxane, PDMS; and divinylbenzene/carboxen/polydimethylsiloxane, DVB/CAR/PDMS) for the analysis of solid samples. The developed method was successfully employed for the analysis of MTBE in different soil samples contaminated by oil products.

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