Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Joshua Padilla; H. Selim

doi:10.3390/soilsystems2030053

Glyphosate Transport in Two Louisiana Agricultural Soils: Miscible Displacement Studies and Numerical Modeling

Soil Systems ◽

10.3390/soilsystems2030053 ◽

2018 ◽

Vol 2 (3) ◽

pp. 53 ◽

Cited By ~ 2

Author(s):

Joshua Padilla ◽

H. Selim

Keyword(s):

Transport Model ◽

Agricultural Soils ◽

Exchange Capacity ◽

Miscible Displacement ◽

Soil Environment ◽

Linear Modeling ◽

Primary Metabolite ◽

Aminomethylphosphonic Acid ◽

Displacement Experiments ◽

Reaction Transport

Glyphosate (N-(phosphonomethyl) glycine) (GPS) is currently the most commonly used herbicide worldwide, and is generally considered as immobile in soils. However, numerous reports of the environmental occurrence of the herbicide coupled with recent evidence of human toxicity necessitate further investigation as to the behavior of GPS in the soil environment. Batch sorption studies along with miscible displacement experiments were carried out in order to assess the mobility of GPS in two Louisiana agricultural soils; Commerce silt loam and Sharkey clay. Batch results indicated a high affinity of both soils for solvated GPS, with greater affinity observed by the Sharkey soil. GPS sorption in the Commerce soil was most likely facilitated by the presence of amorphous Fe and Al oxides, whereas the high cation exchange capacity of the Sharkey soil likely allows for GPS complexation with surface exchangeable poly-valent cations. Miscible displacement studies indicate that GPS mobility is highly limited in both soils, with 3% and 2% of the applied herbicide mass recovered in the effluent solution from the Commerce and Sharkey soils, respectively. A two-site multi-reaction transport model (MRTM) adequately described GPS breakthrough from both soils and outperformed linear modeling efforts using CXTFIT. Analysis of extracted herbicide residues suggests that the primary metabolite of GPS, aminomethylphosphonic acid (AMPA), is more mobile in both soils, although both compounds are strongly retained.

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Transport of Tin and Lead in Soils: Miscible Displacement Experiments and Second-Order Modeling

Soil Science Society of America Journal ◽

10.2136/sssaj2013.07.0265 ◽

2014 ◽

Vol 78 (3) ◽

pp. 701-712 ◽

Cited By ~ 5

Author(s):

Tamer A. Elbana ◽

Donald L. Sparks ◽

H. Magdi Selim

Keyword(s):

Miscible Displacement ◽

Second Order ◽

Displacement Experiments

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Influence of soil tillage and erosion on the dispersion of glyphosate and aminomethylphosphonic acid in agricultural soils

International Agrophysics ◽

10.2478/intag-2013-0031 ◽

2014 ◽

Vol 28 (1) ◽

pp. 93-100 ◽

Cited By ~ 13

Author(s):

Gorana Rampazzo Todorovic ◽

Nicola Rampazzo ◽

Axel Mentler ◽

Winfried E.H. Blum ◽

Alexander Eder ◽

...

Keyword(s):

Agricultural Soils ◽

Soil Tillage ◽

Erosion Risk ◽

Erosion Processes ◽

Run Off ◽

Aminomethylphosphonic Acid ◽

Severe Erosion ◽

Structure State ◽

Key Parameter ◽

Percolation Water

Abstract Erosion processes can strongly influence the dissipation of glyphosate and aminomethylphosphonic acid applied with Roundup Max® in agricultural soils; in addition, the soil structure state shortly before erosive precipitations fall can be a key parameter for the distribution of glyphosate and its metabolite. Field rain simulation experiments showed that severe erosion processes immediately after application of Roundup Max® can lead to serious unexpected glyphosate loss even in soils with a high presumed adsorption like the Cambisols, if their structure is unfavourable. In one of the no-tillage-plot of the Cambisol, up to 47% of the applied glyphosate amount was dissipated with surface run-off. Moreover, at the Chernozem site with high erosion risk and lower adsorption potential, glyphosate could be found in collected percolation water transported far outside the 2x2 m experimental plots. Traces of glyphosate were found also outside the treated agricultural fields.

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Modelling uranium leaching from agricultural soils to groundwater as a criterion for comparison with complementary safety indicators

MRS Proceedings ◽

10.1557/proc-932-2.1 ◽

2006 ◽

Vol 932 ◽

Cited By ~ 5

Author(s):

D. Jacques ◽

J. Šimůnek ◽

D. Mallants ◽

M.Th. van Genuchten

Keyword(s):

Soil Profile ◽

Reactive Transport ◽

Transport Model ◽

Agricultural Soils ◽

Solid Phase ◽

Water Flux ◽

Fertilizer Application ◽

Mineral Fertilizers ◽

Deep Soil ◽

Long Time

ABSTRACTNaturally occurring radionuclides can also end up in soils and groundwater due to human practices, such as application of certain fertilizers in agriculture. Many mineral fertilizers, particularly (super)phosphates, contain small amounts of 238U and 230Th which eventually may be leached from agricultural soils to underlying water resources. Field soils that receive P-fertilizers accumulate U and Th and their daughter nuclides, which eventually may leach to groundwater. Our objective was to numerically assess U migration in soils. Calculations were based on a new reactive transport model, HP1, which accounts for interactions between U and organic matter, phosphate, and carbonate. Solid phase interactions were simulated using a surface complexation module. Furthermore, all geochemical processes were coupled with a model accounting for dynamic changes in the soil water content and the water flux. The capabilities of the code in calculating natural U fluxes to groundwater were illustrated using a semi-synthetic 200-year long time series of climatological data for Belgium. Based on an average fertilizer application, the input of phosphate and uranium in the soil was defined. This paper discusses calculated U distributions in the soil profile as well as calculated U fluxes leached from a 100-cm deep soil profile. The calculated long-term leaching rates originating from fertilization are significantly higher after 200 years than estimated release rates from lowlevel nuclear waste repositories.

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Oxygen consumption rates in subseafloor basaltic crust derived from a reaction transport model

Nature Communications ◽

10.1038/ncomms3539 ◽

2013 ◽

Vol 4 (1) ◽

Cited By ~ 61

Author(s):

Beth N. Orcutt ◽

C. Geoffrey Wheat ◽

Olivier Rouxel ◽

Samuel Hulme ◽

Katrina J. Edwards ◽

...

Keyword(s):

Oxygen Consumption ◽

Transport Model ◽

Consumption Rates ◽

Reaction Transport ◽

Basaltic Crust

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Effect of Oxytetracycline and Chlortetracycline on Bacterial Community Growth in Agricultural Soils

Agronomy ◽

10.3390/agronomy10071011 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1011 ◽

Cited By ~ 4

Author(s):

Vanesa Santás-Miguel ◽

Manuel Arias-Estévez ◽

Montserrat Díaz-Raviña ◽

María José Fernández-Sanjurjo ◽

Esperanza Álvarez-Rodríguez ◽

...

Keyword(s):

Organic Carbon ◽

Bacterial Community ◽

Total Organic Carbon ◽

Agricultural Soils ◽

Exchange Capacity ◽

Soil Parameters ◽

Leucine Incorporation ◽

Negative Effects ◽

Input Variables ◽

Community Growth

Toxicity on soil bacterial community growth caused by the antibiotics oxytetracycline (OTC) and chlortetracycline (CTC) was studied in 22 agricultural soils after 1, 8 and 42 incubation days. The leucine incorporation method was used with this aim, estimating the concentration of each antibiotic which caused an inhibition of 50% in bacterial community growth (log IC50). For OTC, the mean log IC50 was 2.70, 2.81, 2.84 for each of the three incubation times, while the values were 2.05, 2.22 and 2.47 for CTC, meaning that the magnitude of OTC toxicity was similar over time, whereas it decreased significantly for CTC with incubation time. In addition, results showed that the toxicity on bacterial community growth due to CTC is significantly higher than when due to OTC. Moreover, the toxicity on bacterial community growth due to both antibiotics is dependent on soil properties. Specifically, an increase in soil pH and silt content resulted in higher toxicity of both antibiotics, while increases in total organic carbon and clay contents caused decreases in OTC and CTC toxicities. The results also show that OTC toxicity can be well predicted by means of specific equations, using the values of pH measured in KCl and those of effective cation exchange capacity as input variables. CTC toxicity may be predicted (but with low precision) using pH measured in KCl and total organic carbon. These equations may help to predict the negative effects caused by OTC and CTC on soil bacteria using easily measurable soil parameters.

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Influence of long-term mineral fertilization on metal contents and properties of soil samples taken from different locations in Hesse, Germany

SOIL ◽

10.5194/soil-1-23-2015 ◽

2015 ◽

Vol 1 (1) ◽

pp. 23-33 ◽

Cited By ~ 40

Author(s):

S. Czarnecki ◽

R.-A. Düring

Keyword(s):

Cation Exchange ◽

Cation Exchange Capacity ◽

Agricultural Soils ◽

Mineral Fertilizer ◽

Fertilizer Application ◽

Exchange Capacity ◽

Soil Samples ◽

Residual Effects ◽

Metal Contents

Abstract. Essential and non-essential metals occur in soils as a result of weathering, industrial processes, fertilization, and atmospheric deposition. Badly adapted cultivation of agricultural soils (declining pH value, application of unsuitable fertilizers) can enhance the mobility of metals and thereby increase their concentrations in agricultural products. As the enrichment of metals in soils occurs over long time periods, monitoring of the long-term impact of fertilization is necessary to assess metal accumulation in agricultural soils. The main objective of this study was to test the effects of different mineral fertilizer variations on soil properties (pH, Corg, and cation exchange capacity (CEC)) and pseudo-total and mobile metal contents of soils after 14 years of fertilizer application and to determine residual effects of the fertilization 8 years after cessation of fertilizer treatment. Soil samples were taken from a field experiment which was carried out at four different locations (210, 260, 360, and 620 m above sea level) in Hesse, Germany. During the study, a significant decrease in soil pH and an evident increase in soil carbon content and cation exchange capacity with fertilization were determined. The CEC of the soils was closely related to their organic C contents. Moreover, pseudo- and mobile metal (Cd, Cu, Mn, Pb, Zn) contents in the soils increased due to application of 14 years of mineral fertilizer treatments (N, P, NP, and NPK) when compared to control plots. Eight years after termination of the fertilization in the soil samples taken from soil profiles of the fertilized plots (NPK) for monitoring the residual effects of the fertilizer application, a decrease of 82.6, 54.2, 48.5, 74.4, and 56.9% in pseudo-total Cd, Cu, Mn, Pb, and Zn contents, respectively, was determined.

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Agricultural Soils Amended With Thermally-Dried Anaerobically-Digested Sewage Sludge Showed Increased Risk of Antibiotic Resistance Dissemination

Frontiers in Microbiology ◽

10.3389/fmicb.2021.666854 ◽

2021 ◽

Vol 12 ◽

Author(s):

Leire Jauregi ◽

Lur Epelde ◽

Itziar Alkorta ◽

Carlos Garbisu

Keyword(s):

Antibiotic Resistance ◽

Sewage Sludge ◽

Relative Abundance ◽

Agricultural Soils ◽

Antibiotic Resistance Genes ◽

Exchange Capacity ◽

Amended Soils ◽

Α Diversity ◽

Increased Risk ◽

Digested Sewage Sludge

The application of sewage sludge (SS) to agricultural soil can help meet crop nutrient requirements and enhance soil properties, while reusing an organic by-product. However, SS can be a source of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), resulting in an increased risk of antibiotic resistance dissemination. We studied the effect of the application of thermally-dried anaerobically-digested SS on (i) soil physicochemical and microbial properties, and (ii) the relative abundance of 85 ARGs and 10 MGE-genes in soil. Soil samples were taken from a variety of SS-amended agricultural fields differing in three factors: dose of application, dosage of application, and elapsed time after the last application. The relative abundance of both ARGs and MGE-genes was higher in SS-amended soils, compared to non-amended soils, particularly in those with a more recent SS application. Some physicochemical parameters (i.e., cation exchange capacity, copper concentration, phosphorus content) were positively correlated with the relative abundance of ARGs and MGE-genes. Sewage sludge application was the key factor to explain the distribution pattern of ARGs and MGE-genes. The 30 most abundant families within the soil prokaryotic community accounted for 66% of the total variation of ARG and MGE-gene relative abundances. Soil prokaryotic α-diversity was negatively correlated with the relative abundance of ARGs and MGE-genes. We concluded that agricultural soils amended with thermally-dried anaerobically-digested sewage sludge showed increased risk of antibiotic resistance dissemination.

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