Efecto de la adición de organo-hidrotalcita a un suelo agrícola en el comportamiento de los fungicidas tebuconazol y metalaxil bajo condiciones reales de campo

2 páginas.-- 2 tablas.-- 2 referencias.-- Poster presentado en XXIV Reunión de la Sociedad Española de Arcillas Sevilla. Libro de Resúmenes: Noviembre de 2015 en Sevilla.Existen numerosos trabajos que abordan las aplicaciones de arcillas naturales, inalteradas o modificadas, como adsorbentes de pesticidas para la depuración de aguas e incluso para actuar como soportes en formulaciones de liberación lenta del pesticida o como barreras inmovilizantes en suelos (Cornejo et al., 2008). La mayoría de estos estudios se han realizado bajo condiciones controladas en el laboratorio y usando minerales de la arcilla naturales del grupo de las esmectitas. En los últimos años, ha aumentado el interés por explotar las propiedades adsorbentes de los hidróxidos dobles laminares (HDLs), también conocidos como hidrotalcitas (HTs) o arcillas aniónicas, cuyas características estructurales guardan cierta relación con las de las esmectitas (Cornejo et al., 2008). Los LDHs consisten en láminas del tipo brucita de un metal divalente con sustituciones isomórficas que proporcionan a las láminas una carga permanente positiva y que es compensada con aniones intercambiables que se sitúan en el espacio interlaminar. Aunque los resultados obtenidos hasta ahora ponen de manifiesto la elevada capacidad de adsorción de los LDHs para muchos pesticidas y la versatilidad que les confiere la posibilidad de modificarlos mediante la intercalación de aniones orgánicos en el espacio interlaminar (Celis et al., 2014), su utilidad como enmendantes para aumentar la capacidad de adsorción de los suelos bajo condiciones ambientales reales aún no ha sido evaluada.Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad (MINECO) a través de los proyectos AGL2011-23779 y AGL2014-51897-R y por la Junta de Andalucía a través del Grupo de Investigación AGR-264, con parte de fondos FEDER-FSE. R. López-Cabeza agradece al MINECO la concesión de una beca pre-doctoral de FPI asociada al proyecto AGL2011-23779.Peer reviewe

Effect of synthetic clay and biochar addition on dissipation and enantioselectivity of tebuconazole and metalaxyl in an agricultural soil: Laboratory and field experiments

10 páginas.-- 4 figuras.-- 3 tablas.-- referencias.-- Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.agee.2016.05.017Laboratory and field experiments were conducted to assess how the addition of oleate-modified hydrotalcite (clay) and biochar (BC) to an agricultural soil affected the sorption, leaching, persistence, and enantiomeric composition of soil residues of two chiral fungicides, tebuconazole and metalaxyl. Laboratory experiments showed that the sorption of both fungicides ranked as follows: unamended soil < BC-amended soil < clay-amended soil. The addition of clay at a rate of 1% increased metalaxyl soil sorption coefficient (Kd) from 0.34 to 3.14 L kg−1 and that of tebuconazole from 2.4 to 47.4 L kg−1. In our experimental set-up, field plots were either unamended or amended with clay (2 t ha−1) or BC (4 t ha−1), and subsequently treated with a mixture of tebuconazole and metalaxyl at 3 and 6 kg ha−1, respectively. The leaching, persistence, and enantiomer composition of fungicides residues were monitored by sampling at different soil depths (0–5, 5–10, 10–20 cm) for 98 days. No significant changes in the scarce mobility and long persistence of tebuconazole upon amending the soil with clay or BC were observed. In contrast, sorption to clay and BC particles reduced the leaching and degradation of metalaxyl and the clay increased its persistence in the topsoil compared to the unamended soil. The enantioselective analysis of tebuconazole and metalaxyl soil residues indicated that tebuconazole remained mostly racemic along the experiment, whereas for metalaxyl the concentration of S-enantiomer was greater than the concentration of R-enantiomer, more so at longer experimental times and deeper horizons. Nevertheless, for the top 0–5 cm soil layer metalaxyl remained more racemic in clay- and BC-amended soil than in unamended soil. Our results show that addition of amendments with high sorptive capacities can be beneficial in reducing leaching and degradation losses of chiral pesticide enantiomers from the topsoil, and that sorption by the amendments can influence the final enantiomeric composition of pesticide residues.This work was financed by the Spanish Ministry of Economy and Competitiveness (MINECO Projects AGL2011-23779, AGL2013-48446-C3-1-R and AGL2014-51897-R) and Junta de Andalucía (JA Research Group AGR-264), with FEDER-FSE funds. R. López-Cabeza thanks MINECO for a pre-doctoral fellowship linked to the Project AGL2011-23779 (Grant BES-2012-059945). The authors also thank P. Franco (Chiral Technologies Europe) and I. Girón (IRNAS) for their technical assistancePeer reviewe

Efecto del envejecimiento del carbón biológico en la biodisponibilidad y lixiviación del herbicida mesotriona

Tutores del trabajo: Gámiz, B.; Cox, L.; Florido Fernández, M.C

Influencia de la adición de enmiendas y residuos orgánicos en el comportamiento de los herbicidas dicamba y 2,4-D en suelos

81 páginas.-- 191 figuras.-- 7 tablas.-- 89 referencias.-- Memoria presentada en el XXXVIII Curso Internacional de Edafología y Biología Vegetal, 2001.Directora del trabajo: Cox, LucíaLa adición de enmiendas y residuos orgánicos al suelo es una práctica habitual que tiene como objetivo mejorar las propiedades físicas y quúnicas de los medios así como, en el caso de los residuos, una vía altemativa de eliminación de los mismos. El objetivo de este trabajo es estudiar la influencia que tiene esta práctica en la adsorción, degradación y movílidad de herbicidas, así como en las propiedades físicas (en particualla porosidad) del suelo. Se seleccionarán dos herbicidas, dicamba y 2,4-D Y un suelo vega, al cual se le añadirán cuatro enmiendas orgánicas diferentes: dos enmiendas húmicas comerciales y dos residuos (un lodo de depuradora y un residuo sólido urbano). Despues de mezclar el suelo, secarlo y tamizarlo, se realizarán expeliencias de adsorción-desorción mediante la realización de isotelmas de adsorcióndesorción. La movilidad de dicamba y 2,4-D en los suelos enmendados y en el suelo sin enmendar se estudiará mediante colunmas de suelo empaquetadas manualmente. La degradación de dicamba y 2,4-D se estudiará mediante incubaciones del suelo a un contenido de humedad de -0.33 bar y 22 oc. Estudiaremos la influencia de las diferentes enmiendas orgánicas en la porosidad del suelo mediante la técnica de poro simetría de mercurio y realizaremos un bioensayo para ver la bioefectivídad del herbicida especialmente en el caso de los suelos enmendados.Beca AECIPeer reviewe

Cambios en la adsorción/biodisponibilidad de dos fungicidas con el tiempo de residencia en el suelo

4 páginas, 2 figuras, 3 tablas, 18 referencias. El libro de resúmenes consta de 414 páginas.[ES]: Se han determinado los cambios en la distribución fase adsorbida/fase en solución del suelo de los fungicidas metalaxyl y triciclazol con el tiempo de residencia en el suelo. Tres suelos de diferentes características físico-químicas se trataron con los fungicidas y se incubaron 30 días a 20 0C y humedad del 40 % de la capacidad máxima de retención de agua del suelo. Los coeficientes de distribución Kd para triciclazol fueron mayores que para metalaxil en los tres suelos, y para ambos fungicidas fueron mayores en los suelos con alto contenido en materia orgánica y/o arcilla. Con el tiempo de residencia en el suelo, los coeficientes Kd de metalaxyl tan sólo aumentaron en el caso del suelo de mayor contenido en materia orgánica, mientras que en el caso de triciclazol los valores de Kd aumentaron en el caso del suelo de mayor contenido en materia orgánica y en el suelo de mayor contenido en arcilla y bajo contenido en materia orgánica.[EN]: The present study was conducted to determine the changes in distribution between sorbed and solution phases of the fungicides metalaxyl and tricyclazole with incubation time. Three different soils were selected for this study, treated with the fungicides, and incubated for 30 days at 20 ºC and soil moisture content equivalent to 40 % of soil water holding capacity. Distribution coefficients Kd for tricyclazole were higher than for metalaxyl in the three soils considered, and as in the case of metalaxyl increased with organic matter and/or clay content of the soil. With aging, Kd for metalaxyl only increased in the case of the soil of higher organic matter content, whereas in the case of tricyclazole Kd values increased with incubation time in the soil of highest organic matter content and in a soil with very high clay content and low organic matter content.Este trabajo ha sido financiado con el proyecto AGL 2001-1554 del Ministerio de Ciencia y Tecnologia y RNM 124 de la Junta de Andalucía. M.C. Fernandes agradece a la Fundación de Ciencia y Tecnología de Portugal por su beca predoctoral BFRH/BD/721/2000 del Programa POCTI.Peer reviewe

Fate of diuron and terbuthylazine in soils amended with two-phase olive oil mill waste

The addition of organic amendments to soil increases soil organic matter content and stimulates soil microbial activity. Thus, processes affecting herbicide fate in the soil should be affected. The objective of this work was to investigate the effect of olive oil production industry organic waste (alperujo) on soil sorption-desorption, degradation, and leaching of diuron [3-(3,4-dichlorophenyl)-1,1 -dimethylurea] and terbuthylazine [N 2-fert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine] , two herbicides widely used in olive crops. The soils used in this study were a sandy soil and a silty clay soil from two different olive groves. The sandy soil was amended in the laboratory with fresh (uncomposted) alperujo at the rate of 10% w/w, and the silty clay soil was amended in the field with fresh alperujo at the rate of 256 kg per tree during 4 years and in the laboratory with fresh or composted alperujo. Sorption of both herbicides increased in laboratory-amended soils as compared to unamended or field-amended soils, and this process was less reversible in laboratory-amended soils, except for diuron in amended sandy soil. Addition of alperujo to soils increased half-lives of the herbicides in most of the soils. Diuron and terbuthylazine leached through unamended sandy soil, but no herbicide was detected in laboratory-amended soil. Diuron did not leach through amended or unamended silty clay soil, whereas small amounts of terbuthylazine were detected in leachates from unamended soil. Despite their higher sorption capacity, greater amounts of terbuthylazine were found in the leachates from amended silty clay soils. The amounts of dissolved organic matter from alperujo and the degree of humification can affect sorption, degradation, and leaching of these two classes of herbicides in soils. It appears that adding alperujo to soil would not have adverse impacts on the behavior of herbicides in olive production.This work has been partially financed by Project AGL 2004-05818-CO2-01 from the Spanish MEC and Research Group RNM 124 of Junta de Andalucía. A.C. thanks the MEC for her FPI fellowship.Peer Reviewe

Evaluation of biochar addition to an agricultural soil on the fate and bioavailability of the herbicide clomazone

Three natural smectitic clays (SWy-2, CTI and SH) were modified with one inorganic cation (FE3+) and one biopolymeric (chitosan, ch) cation with the aim to increase the adsorption capacity of those mineral clays for tricyclazole. The sorption capacity of the clays was assessed to increase, with the greatest adsorption (>93%) for natural clays modified with Fe3+ . Three types of clay-tricyclazol complexes (ground mixing, GM; weak complex, WC; and strong complex,SC) were prepared and tested as controlled release formulations (çCRFs). The release of tricyclazole in water decreased from the GMs of the CTIFe (85%), SWch4 (84%) and SWch6 (77%), showing lower values than the commercial product (100%) . Soil leaching depended on the soil type: Triciclazole was not detected in any leachate and alluvial soil, but in the sandy the SWch6 WC reduced tricyclazole leaching (65%) from the commercial formulation (75%). Clay tricyclzol complexes andr shown as usefull CRFs to minimize water contamination potential of this fungicide.CSIC (JAE-doc) Junta de Andalucía AGR-264 and P11-AGR 7400 cofinanciado EU-FEDER-FSE (PO 2009-2013)Peer Reviewe

Terbuthylazine persistence in an organic amended soil

The aim of this work was to study the effect of the application of a solid waste from olive oil production (alperujo) on the movement and persistence of the herbicide terbuthylazine (N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2, 4-diamine). An experimental olive grove was divided in two plots: (i) Plot without organic amendment (blank) and (ii) Plot treated with alperujo during 3 years at a rate of 17920 kg of alperujo ha- 1. Terbuthylazine was applied to both plots at a rate of 2 kg ha- 1 a.i. Triplicates from each plot were sampled at 3 depths (0-10, 10-20 and 20-30 cm), air-dried, remains of olive leaves, grass roots, and stones removed and sieved through a 5 mm mesh sieve. Terbuthylazine was extracted with methanol 1:2 weight:volume ratio, the extracts were evaporated to dryness, resuspended in 2 mL of methanol, filtered and anylized by high performance liquid chromatography (HPLC). Higher amounts of terbuthylazine were detected at each sampling depth in plots treated with alperujo. The increase in soil organic matter content upon amendment with alperujo slightly increased sorption, suggesting that other factors beside sorption affect terbuthylazine degradation rate in organic amended soils.Peer Reviewe

Dynamic Effect of Fresh and Aged Biochar on the Behavior of the Herbicide Mesotrione in Soils

10 páginas.- 6 figuras.- 5 tablas.- 57 referencias.- The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jafc.9b02618In this study, we assessed the sorption, dissipation, and leaching of the herbicide mesotrione in soil amended with fresh and field-aged biochars, when added to the soil. The aging process was performed by burying the fresh biochar at 10 cm depth in three soils located in different points across the USA [Wisconsin (ABC_WI), Idaho (ABC_ID), and South Carolina (ABC_SC)] for six months. ABC_ID and ABC_SC slightly increased the sorption of mesotrione in soils, whereas ABC_WI removed greater amounts of herbicide from the solution. This was attributed to differences in water-soluble components and metal content of this aged biochar. Consequently, the persistence of the herbicide in the amended soils with fresh biochar and ABC_ID and ABC_SC were similar to that in unamended soils, while ABC_WI slightly increased mesotrione half-life. Differences between treatments were detected in leaching studies although no direct relationship with the dissipation batch studies was observed. Mesotrione leaching could not be detected in soil columns amended with ABC_WI and was high for the rest of treatments. The outcomes from this work demonstrate that temporal variability of biochar sorption capacities due to soil exposure can occur altering mesotrione’s behavior in biochar-amended soils.This work was financed by the Spanish Ministry of Science, Innovation and Universities (MICINN Project AGL2016-77821-R). B.G. thanks MICINN for her Juan de la Cierva Incorporacion postdoctoral contract (IJCI-2015-23309).Peer reviewe

The Role of Nanoengineered Biochar Activated with Fe for Sulfanilamide Removal from Soils and Water

14 páginas.- 5 figuras.- 4 tablas.- 71 referencias.- Supplementary Materials: The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules27217418/s1 .- his article belongs to the Special Issue Organic Nanomaterials: Synthesis and ApplicationsBiochar is a nanoengineered sorbent proposed to control the contamination derived from the presence of residual concentrations of sulfonamides in soil. In this work, we evaluated the sorption of sulfanilamide (SFA) in commercial biochar (BC) produced at 500 °C from oak hardwood (Quercus ilex) and its analog activated with 2% (w/w) Fe (BC-Fe). Subsequently, the effect on dissipation and transport of SFA in untreated soil and soil treated with BC and BC-Fe was also assessed. Laboratory batch studies revealed that BC-Fe increased the sorption of SFA as compared to the pristine BC with Kd of 278 and 98 L/kg, respectively. The dissipation of SFA in either untreated soil or soil treated with BC or BC-Fe was similar, displaying half-lives ranging between 4 and 6.4 days. Conversely, the concurrent determination of sorption during the incubation experiment showed that lower amounts of SFA in solution at the beginning of the experiments were bioavailable in BC-Fe-treated soil when compared to the rest of the treatments shortly after application. Leaching column studies confirmed the amendment’s capability to bind the SFA compound. Therefore, the decrease in bioavailability and movement of SFA in treated soils suggest that biochar soil application can reduce SFA soil and water contamination. According to our results, BC surface modification after Fe activation may be more appropriate for water decontamination than for soil since there were no significant differences between the two types of biochar when added to the soil. Therefore, these outcomes should be considered to optimize the SFA mitigation potential of biochar.This research was funded by the Spanish Ministry of Science and Innovation (MCIN/AEI/10.13039/501100011033) through grants PID2019-109456RB-I00 and by Junta de Andalucía, through grant P20-00746, with EU (FEDER) funds. The USDA is an equal-opportunity employer. Any mention of trade names or commercial products in this report is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. Institutional Review Board StatementPeer reviewe