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María E. Báez - One of the best experts on this subject based on the ideXlab platform.

  • sorption desorption behavior of pesticides and their degradation products in volcanic and nonvolcanic soils interpretation of interactions through two way principal component analysis
    Environmental Science and Pollution Research, 2015
    Co-Authors: María E. Báez, Jeannette Espinoza, Ricardo Silva, Edwar Fuentes
    Abstract:

    Sorption-desorption behavior of six pesticides and some degradation products was assessed on seven agricultural volcanic and nonvolcanic soils belonging to Andisol, Ultisol, Mollisol, and Alfisol orders. The global interpretation of sorption data was performed by principal component analysis. Results showed exceptionally high sorption of glyphosate and aminomethylphosphonic acid (AMPA) (the breakdown product) on volcanic soils (Kf > 1500 μg1 − 1 / n mL1 / n g−1) related mainly to contents of amorphous aluminum oxides (Andisols) and crystalline minerals (Ultisols). The lower sorption on nonvolcanic soils was associated to low organic matter contents and lack of significant minerals. Metsulfuron-methyl and 3,5,6-trichloro-2-pyridinol (metabolite of chlorpyrifos) were weakly to substantially sorbed on Andisols and Ultisols, but the first one was not sorbed at pH > 6.4, including nonvolcanic soils. The metabolite of diazinon, 2-isopropyl-4-methyl-6-hydroxypyrimidine, was weakly sorbed on all soils (Kf = 0.4 to 3.6 μg1 − 1 / n mL1 / n g−1). Acidic compounds would be lixiviated in Mollisols and Alfisols, but they could leach also in Andisols and Ultisols if they reach greater depths. Atrazine and deethylatrazine sorption was related to organic carbon content; therefore, they were weakly retained on nonvolcanic soils (Kf = 0.7 to 2.2 μg1 − 1 / n mL1 / n g−1). Chlorpyrifos was highly sorbed on all soils reaching KOC values of >8000. Finally, the significant retention of chlorothalonil and diazinon on Mollisols and Alfisols in spite of their low OC contents showed the contribution of clay minerals in the sorption process.

  • characterization of the atrazine sorption process on Andisol and ultisol volcanic ash derived soils kinetic parameters and the contribution of humic fractions
    Journal of Agricultural and Food Chemistry, 2013
    Co-Authors: María E. Báez, Edwar Fuentes, Jeannette Espinoza
    Abstract:

    Atrazine sorption was studied in six Andisol and Ultisol soils. Humic and fulvic acids and humin contributions were established. Sorption on soils was well described by the Freundlich model. Kf values ranged from 2.2–15.6 μg1–1/nmL1/ng–1. The relevance of humic acid and humin was deduced from isotherm and kinetics experiments. KOC values varied between 221 and 679 mLg–1 for these fractions. Fulvic acid presented low binding capacity. Sorption was controlled by instantaneous equilibrium followed by a time-dependent phase. The Elovich equation, intraparticle diffusion model, and a two-site nonequilibrium model allowed us to conclude that (i) there are two rate-limited phases in Andisols related to intrasorbent diffusion in organic matter and retarded intraparticle diffusion in the organo–mineral complex and that (ii) there is one rate-limited phase in Ultisols attributed to the mineral composition. The lower organic matter content of Ultisols and the slower sorption rate and mechanisms involved must be cons...

  • modeling the sorption kinetic of metsulfuron methyl on Andisols and ultisols volcanic ash derived soils kinetics parameters and solute transport mechanisms
    Journal of Hazardous Materials, 2010
    Co-Authors: Lizethly Caceres, Edwar Fuentes, Mauricio Escudey, María E. Báez
    Abstract:

    Metsulfuron-methyl sorption kinetic was studied in Andisol and Ultisol soils in view of their distinctive physical and chemical properties: acidic pH and variable surface charge. Different kinetic models were applied to the experimental results. The pseudo-second-order model fitted sorption kinetics data better than the pseudo-first-order model. The rate constant and the initial rate constant values obtained through this model demonstrated the different behavior of metsulfuron-methyl in both kinds of soils, both parameters being the highest for Andisol. The application of Elovich equation, intraparticle diffusion model and a two-site nonequilibrium model (TSNE) allowed to conclude that: (i) the high organic matter content is the governing factor for Andisols where mass transfer across the boundary layer, and in a lesser degree, intraparticle diffusion were the two processes controlling sorption kinetic and (ii) the mineral composition was more relevant in Ultisols where rate was controlled almost exclusively by intraparticle diffusion into macropores and micropores. The slower sorption rate on Ultisols, the mechanism involved and the lower sorption capacity of this kind of soils must be taken into account to assess leaching behavior of this herbicide.

  • metsulfuron methyl sorption desorption behavior on volcanic ash derived soils effect of phosphate and ph
    Journal of Agricultural and Food Chemistry, 2010
    Co-Authors: Lizethly Caceres, Edwar Fuentes, Mauricio Escudey, Roxana Fuentes, María E. Báez
    Abstract:

    Metsulfuron-methyl sorption/desorption behavior was studied through batch sorption experiments in three typical volcanic ash-derived soils belonging to Andisol and Ultisol orders. Their distinctive physical and chemical properties are acidic pH and variable surface charge. Organic matter content and mineral composition affected in different ways sorption of metsulfuron-methyl (KOC ranging from 113 to 646 mL g -1 ): organic matter and iron and aluminum oxides mainly through hydrophilic rather than hydrophobic interactions in Andisols, and Kaolinite group minerals, as major constituents of Ultisols, and iron and aluminum oxides only through hydrophilic interactions. The Freundlich model described metsulfuron-methyl behavior in all cases (R 2 > 0.992). Kf values (3.1-14.4 μg 1-1/n mL 1/n g -1 ) were higher than those reported for different class of soils including some with variable charge. Hysteresis was more significant in Ultisols. A strong influence of pH and phosphate was established for both kinds of soil, intensive soil fertilization and liming being the most probable scenario for leaching of metsulfuron-methyl, particularly in Ultisols.

  • adsorption of glyphosate on variable charge volcanic ash derived soils
    Journal of Environmental Quality, 2009
    Co-Authors: L Caceresjensen, María E. Báez, Jianying Gan, Romulo Fuentes, Mauricio Escudey
    Abstract:

    Glyphosate (N-phosphonometylglycine) is widely used due to its broad spectrum of activity and nonselective mode of action. In Chile it is the most used herbicide, but its adsorption behavior in the abundant and widespread variable charge soils is not well understood. In this study, three volcanic ash-derived soils were selected, including Andisols (Nueva Braunau and Diguillin) and Ultisols (Collipulli), to evaluate the adsorption kinetics, equilibrium isotherms, and the effect of pH in glyphosate adsorption. The influence of glyphosate on soil phosphorus retention was also studied. Glyphosate was rapidly and strongly adsorbed on the selected soils, and adsorption isotherms were well described by the Freundlich relationship with strong nonlinearity (n(fads) < 0.5). The n(fads) values were consistently higher than n(fdes) values, suggesting strong hysteresis. Adsorption (K(ads)) increased strongly when pH decreased. The presence of glyphosate (3200 mug mL(-1)) changed the adsorption behavior of phosphate at its maximum adsorption capacity. Andisol soils without the addition of glyphosate had similar mean K(ads) values for Nueva Braunau (5.68) and Diguillin (7.38). Collipulli had a mean K(ads) value of 31.58. During the successive desorption steps, glyphosate at the highest level increased K(ads) values for phosphate in the Andisol soils but had little effect in the Ultisol soil. This different behavior was probably due to the irreversible occupation of some adsorption sites by glyphosate in the Ultisol soil attributed to the dominant Kaolinite mineral. Results from this study suggest that in the two types of volcanic soils, different mechanisms are involved in glyphosate and phosphate adsorption and that long-term use of glyphosate may impose different effects on the retention and availability of phosphorus. Volcanic ash-derived soils have a particular environmental behavior in relation to the retention of organic contaminants, representing an environmental substrate that may become highly polluted over time due to intensive agronomic uses.

Adrien-jules Herbillon - One of the best experts on this subject based on the ideXlab platform.

  • Characteristics of non-allophanic Andisols derived from low-activity clay regoliths in the Nilgiri Hills (Southern India)
    European Journal of Soil Science, 2000
    Co-Authors: L. Caner, Gérard Bourgeon, Francois Toutain, Adrien-jules Herbillon
    Abstract:

    Summary Low-activity clay soils on old planation surfaces of the tropics are generally considered as stable end points of soil formation. It is therefore surprising to find Andisols on them. We characterized the properties of six profiles representative of these soils in the western part of the Nilgiri Hills (2000–2500 m above mean sea level), Southern India, where the present climatic conditions are cool (mean annual temperature 15°C) and humid (mean annual rainfall 2500 mm). Thick (50–80 cm) dark-reddish brown topsoil overlies strongly desilicated yellowish-red materials. This horizon has andic properties to a sufficient depth and the carbon content requirement of the melanic epipedon to place these soils in the Andisol order. Our data as well as the history of the Nilgiri Hills suggest that the formation of these non-allophanic Andisols resulted from the succession of two main steps. First, a ‘lateritic’ weathering cycle led to the relative accumulation of secondary Al and Fe oxides. Later, the accumulation of organic matter favoured by a more recent climatic change induced complexation by organic acids of Al and Fe oxides, and the production of enough metal–humus complexes to give rise to andic properties. Such soils, in which secondary Al and Fe oxides, generally considered as indicators of an advanced weathering stage, are involved in a new cycle of soil formation, are original Andisols.

  • Characteristics of Non-Allophanic Andisols derived from Low Activity Clay Regoliths in Nilgiri Hills (Southern India)
    European Journal of Soil Science, 2000
    Co-Authors: L. Caner, Gérard Bourgeon, Francois Toutain, Adrien-jules Herbillon
    Abstract:

    Low activity clay soils on old planation surfaces of the tropics are generally considered as stable end points of soil formation. It is therefore surprising to find Andosols on them. We characterised the properties of six profiles representative of these soils in the Western part of Nilgiri Hills (2000–2500 m above mean sea level), Southern India, where the present climatic conditions are cool (mean annual temperature 15°C) and humid (mean annual rainfall 2500 mm). Thick (50–80 cm) dark–reddish brown topsoil overlies strongly desilicated yellowish–red materials. This horizon has andic properties to a sufficient depth and the carbon content requirement of the melanic epipedon to place these soils in the Andisol order. Our data as well as the history of the Nilgiri Hills suggest that the formation of these non-allophanic Andisols result from the succession of two main steps. First, a ‘lateritic' weathering cycle led to the relative accumulation of secondary Al and Fe oxides. Later, the accumulation of organic matter favoured by a more recent climatic change induced complexation by organic acids of Al and Fe oxides, and the production of enough metal–humus complexes to give rise to andic properties. Such soils, in which secondary Al and Fe oxides, generally considered as indicators of an advanced weathering stage, are involved in a new cycle of soil formation, are original Andisols.

L. Caner - One of the best experts on this subject based on the ideXlab platform.

  • Characteristics of non-allophanic Andisols derived from low-activity clay regoliths in the Nilgiri Hills (Southern India)
    European Journal of Soil Science, 2000
    Co-Authors: L. Caner, Gérard Bourgeon, Francois Toutain, Adrien-jules Herbillon
    Abstract:

    Summary Low-activity clay soils on old planation surfaces of the tropics are generally considered as stable end points of soil formation. It is therefore surprising to find Andisols on them. We characterized the properties of six profiles representative of these soils in the western part of the Nilgiri Hills (2000–2500 m above mean sea level), Southern India, where the present climatic conditions are cool (mean annual temperature 15°C) and humid (mean annual rainfall 2500 mm). Thick (50–80 cm) dark-reddish brown topsoil overlies strongly desilicated yellowish-red materials. This horizon has andic properties to a sufficient depth and the carbon content requirement of the melanic epipedon to place these soils in the Andisol order. Our data as well as the history of the Nilgiri Hills suggest that the formation of these non-allophanic Andisols resulted from the succession of two main steps. First, a ‘lateritic’ weathering cycle led to the relative accumulation of secondary Al and Fe oxides. Later, the accumulation of organic matter favoured by a more recent climatic change induced complexation by organic acids of Al and Fe oxides, and the production of enough metal–humus complexes to give rise to andic properties. Such soils, in which secondary Al and Fe oxides, generally considered as indicators of an advanced weathering stage, are involved in a new cycle of soil formation, are original Andisols.

  • Characteristics of Non-Allophanic Andisols derived from Low Activity Clay Regoliths in Nilgiri Hills (Southern India)
    European Journal of Soil Science, 2000
    Co-Authors: L. Caner, Gérard Bourgeon, Francois Toutain, Adrien-jules Herbillon
    Abstract:

    Low activity clay soils on old planation surfaces of the tropics are generally considered as stable end points of soil formation. It is therefore surprising to find Andosols on them. We characterised the properties of six profiles representative of these soils in the Western part of Nilgiri Hills (2000–2500 m above mean sea level), Southern India, where the present climatic conditions are cool (mean annual temperature 15°C) and humid (mean annual rainfall 2500 mm). Thick (50–80 cm) dark–reddish brown topsoil overlies strongly desilicated yellowish–red materials. This horizon has andic properties to a sufficient depth and the carbon content requirement of the melanic epipedon to place these soils in the Andisol order. Our data as well as the history of the Nilgiri Hills suggest that the formation of these non-allophanic Andisols result from the succession of two main steps. First, a ‘lateritic' weathering cycle led to the relative accumulation of secondary Al and Fe oxides. Later, the accumulation of organic matter favoured by a more recent climatic change induced complexation by organic acids of Al and Fe oxides, and the production of enough metal–humus complexes to give rise to andic properties. Such soils, in which secondary Al and Fe oxides, generally considered as indicators of an advanced weathering stage, are involved in a new cycle of soil formation, are original Andisols.

Mauricio Escudey - One of the best experts on this subject based on the ideXlab platform.

  • modeling the sorption kinetic of metsulfuron methyl on Andisols and ultisols volcanic ash derived soils kinetics parameters and solute transport mechanisms
    Journal of Hazardous Materials, 2010
    Co-Authors: Lizethly Caceres, Edwar Fuentes, Mauricio Escudey, María E. Báez
    Abstract:

    Metsulfuron-methyl sorption kinetic was studied in Andisol and Ultisol soils in view of their distinctive physical and chemical properties: acidic pH and variable surface charge. Different kinetic models were applied to the experimental results. The pseudo-second-order model fitted sorption kinetics data better than the pseudo-first-order model. The rate constant and the initial rate constant values obtained through this model demonstrated the different behavior of metsulfuron-methyl in both kinds of soils, both parameters being the highest for Andisol. The application of Elovich equation, intraparticle diffusion model and a two-site nonequilibrium model (TSNE) allowed to conclude that: (i) the high organic matter content is the governing factor for Andisols where mass transfer across the boundary layer, and in a lesser degree, intraparticle diffusion were the two processes controlling sorption kinetic and (ii) the mineral composition was more relevant in Ultisols where rate was controlled almost exclusively by intraparticle diffusion into macropores and micropores. The slower sorption rate on Ultisols, the mechanism involved and the lower sorption capacity of this kind of soils must be taken into account to assess leaching behavior of this herbicide.

  • metsulfuron methyl sorption desorption behavior on volcanic ash derived soils effect of phosphate and ph
    Journal of Agricultural and Food Chemistry, 2010
    Co-Authors: Lizethly Caceres, Edwar Fuentes, Mauricio Escudey, Roxana Fuentes, María E. Báez
    Abstract:

    Metsulfuron-methyl sorption/desorption behavior was studied through batch sorption experiments in three typical volcanic ash-derived soils belonging to Andisol and Ultisol orders. Their distinctive physical and chemical properties are acidic pH and variable surface charge. Organic matter content and mineral composition affected in different ways sorption of metsulfuron-methyl (KOC ranging from 113 to 646 mL g -1 ): organic matter and iron and aluminum oxides mainly through hydrophilic rather than hydrophobic interactions in Andisols, and Kaolinite group minerals, as major constituents of Ultisols, and iron and aluminum oxides only through hydrophilic interactions. The Freundlich model described metsulfuron-methyl behavior in all cases (R 2 > 0.992). Kf values (3.1-14.4 μg 1-1/n mL 1/n g -1 ) were higher than those reported for different class of soils including some with variable charge. Hysteresis was more significant in Ultisols. A strong influence of pH and phosphate was established for both kinds of soil, intensive soil fertilization and liming being the most probable scenario for leaching of metsulfuron-methyl, particularly in Ultisols.

  • adsorption of glyphosate on variable charge volcanic ash derived soils
    Journal of Environmental Quality, 2009
    Co-Authors: L Caceresjensen, María E. Báez, Jianying Gan, Romulo Fuentes, Mauricio Escudey
    Abstract:

    Glyphosate (N-phosphonometylglycine) is widely used due to its broad spectrum of activity and nonselective mode of action. In Chile it is the most used herbicide, but its adsorption behavior in the abundant and widespread variable charge soils is not well understood. In this study, three volcanic ash-derived soils were selected, including Andisols (Nueva Braunau and Diguillin) and Ultisols (Collipulli), to evaluate the adsorption kinetics, equilibrium isotherms, and the effect of pH in glyphosate adsorption. The influence of glyphosate on soil phosphorus retention was also studied. Glyphosate was rapidly and strongly adsorbed on the selected soils, and adsorption isotherms were well described by the Freundlich relationship with strong nonlinearity (n(fads) < 0.5). The n(fads) values were consistently higher than n(fdes) values, suggesting strong hysteresis. Adsorption (K(ads)) increased strongly when pH decreased. The presence of glyphosate (3200 mug mL(-1)) changed the adsorption behavior of phosphate at its maximum adsorption capacity. Andisol soils without the addition of glyphosate had similar mean K(ads) values for Nueva Braunau (5.68) and Diguillin (7.38). Collipulli had a mean K(ads) value of 31.58. During the successive desorption steps, glyphosate at the highest level increased K(ads) values for phosphate in the Andisol soils but had little effect in the Ultisol soil. This different behavior was probably due to the irreversible occupation of some adsorption sites by glyphosate in the Ultisol soil attributed to the dominant Kaolinite mineral. Results from this study suggest that in the two types of volcanic soils, different mechanisms are involved in glyphosate and phosphate adsorption and that long-term use of glyphosate may impose different effects on the retention and availability of phosphorus. Volcanic ash-derived soils have a particular environmental behavior in relation to the retention of organic contaminants, representing an environmental substrate that may become highly polluted over time due to intensive agronomic uses.

Cut Fajrina - One of the best experts on this subject based on the ideXlab platform.

  • KAJIAN FRAKSI FE DAN AL HUMUS PADA BEBERAPA JENIS TANAH DI LAHAN KERING ACEH BESAR
    Fakultas Pertanian Universitas Syiah Kuala, 2018
    Co-Authors: Cut Fajrina
    Abstract:

    Kabupaten Aceh Besar memiliki lahan kering seluas 278,581 hektar yang terbentukatas beberapa jenis tanah seperti Litosol, Regosol, Aluvial, Renzina, Mollisol, Andosol,Kambisol, Podsolik dan Oksisol. Beberapa permasalahan yang sering di temukan pada sistempertanian lahan kering di wilayah tropika basah antara lain pH tanah rendah, kandungan Corganik rendah, miskin unsur hara, kapasitas tukar kation dan kejenuhan basa rendah, fiksasifosfat yang tinggi, masalah erosi dan ketersediaan air. Tanah-tanah yang berada di daerahiklim tropis tersebut digolongkan sebagai tanah dengan sistem muatan variabel dan memilikiliat aktivitas rendah (low activity clay).Penelitian ini bertujuan untuk mengetahui kadar Fe- dan Al-humus serta C-organikmenurut horison pada setiap ordo tanah dan mengetahui distribusi dan pola distribusi Fe- danAl-humus serta C-organik pada masing-masing ordo tanah. Penelitian ini menggunakanmetode survai deskriptif yaitu melalui kegiatan observasi lapangan dan analisis laboratoriumuntuk mengumpulkan data.Hasil penelitian didapatkan bahwa kandungan tertinggi baik Fe-humus maupun Alhumus terdapat pada ordo Mollisol. Fe-humus terdapat pada horison Ap, Bk1 dan Bk2 yaitu0,14%, sedangkan Al-humus terdapat pada horison Bk1 yaitu 7,53% dan C-organik tertinggiterdapat pada horison Ap ordo Andisol yaitu 4,44%. Kandungan C-organik di lahan keringKabupaten Aceh Besar pada jenis tanah Entisol, Inceptisol, Mollisol dan Ultisol tergolong kedalam kriteria sangat rendah sampai rendah, sedangkan pada Andisol tergolong sangat rendahsampai tinggi dan pada tanah Oxisol tergolong sangat rendah. Sebaran Fe-humus, Al-humusdan C-organik pada enam ordo tanah di lahan kering Aceh Besar membentuk pola yangbervariasi. Pola distribusi Fe-humus pada kedalaman 80 - 125 cm ordo Inceptisol, Andisol,Mollisol dan Ultisol semakin menurun, sedangkan pada Entisol dan Oxisol semakinmeningkat. Pola distribusi Al-humus pada kedalaman 85 - 125 cm pada enam ordo tanahsemakin menurun, sedangkan pada kedalaman 20 - 125 cm pola distribusi C-organik semakinmenurun dengan bertambahnya kedalaman tanah.Banda Ace

  • KAJIAN FRAKSI FE DAN AL HUMUS SERTA C ORGANIK PADA BEBERAPA JENIS TANAH DI LAHAN KERING ACEH BESAR
    'Badan Penerbitan Fakultas Pertanian (BPFP) Universitas Bengkulu', 2018
    Co-Authors: Cut Fajrina
    Abstract:

    Kabupaten Aceh Besar memiliki lahan kering seluas 278,581 hektar yang terbentuk atas beberapa jenis tanah seperti Litosol, Regosol, Aluvial, Renzina, Mollisol, Andosol, Kambisol, Podsolik dan Oksisol. Beberapa permasalahan yang sering di temukan pada sistem pertanian lahan kering di wilayah tropika basah antara lain pH tanah rendah, kandungan C organik rendah, miskin unsur hara, kapasitas tukar kation dan kejenuhan basa rendah, fiksasi fosfat yang tinggi, masalah erosi dan ketersediaan air. Tanah-tanah yang berada di daerah iklim tropis tersebut digolongkan sebagai tanah dengan sistem muatan variabel dan memiliki liat aktivitas rendah (low activity clay). Penelitian ini bertujuan untuk mengetahui kadar Fe- dan Al-humus serta C-organik menurut horison pada setiap ordo tanah dan mengetahui distribusi dan pola distribusi Fe- dan Al-humus serta C-organik pada masing-masing ordo tanah. Penelitian ini menggunakan metode survai deskriptif yaitu melalui kegiatan observasi lapangan dan analisis laboratorium untuk mengumpulkan data. Hasil penelitian didapatkan bahwa kandungan tertinggi baik Fe-humus maupun Al-humus terdapat pada ordo Mollisol. Fe-humus terdapat pada horison Ap, Bk1 dan Bk2 yaitu 0,14%, sedangkan Al-humus terdapat pada horison Bk1 yaitu 7,53% dan C-organik tertinggi terdapat pada horison Ap ordo Andisol yaitu 4,44%. Kandungan C-organik di lahan kering Kabupaten Aceh Besar pada jenis tanah Entisol, Inceptisol, Mollisol dan Ultisol tergolong ke dalam kriteria sangat rendah sampai rendah, sedangkan pada Andisol tergolong sangat rendah sampai tinggi dan pada tanah Oxisol tergolong sangat rendah. Sebaran Fe-humus, Al-humus dan C-organik pada enam ordo tanah di lahan kering Aceh Besar membentuk pola yang bervariasi. Pola distribusi Fe-humus pada kedalaman 80 - 125 cm ordo Inceptisol, Andisol, Mollisol dan Ultisol semakin menurun, sedangkan pada Entisol dan Oxisol semakin meningkat. Pola distribusi Al-humus pada kedalaman 85 - 125 cm pada enam ordo tanah semakin menurun, sedangkan pada kedalaman 20 - 125 cm pola distribusi C-organik semakin menurun dengan bertambahnya kedalaman tanah.Banda Ace