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Aranzazu Pena - One of the best experts on this subject based on the ideXlab platform.
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contribution by different organic fractions to triazines sorption in calcaric regosol amended with raw and biotransformed Olive Cake
Journal of Hazardous Materials, 2010Co-Authors: Laura Delgadomoreno, Aranzazu Pena, G AlmenbdrosAbstract:Abstract A soil, Olive Cake, compost and vermicompost of Olive Cake, were subjected to sequential laboratory extraction to progressively remove water-soluble, lipid and alkali-soluble (humic-type) fractions. Sorption experiments with triazines were carried out with non-amended and amended soil and with soil residues in the intermediate stages during the laboratory removal of the different organic fractions. Herbicide sorption in soil amended with Olive Cake was between two and three times higher than sorption in composted substrates. In non-amended soil, the removal of humic and fulvic acids led to a decrease of triazines sorption indicating the importance of these fractions in the sorption of these pesticides. The greater triazines sorption in soil amended with Olive Cake could be associated with the high concentration of water-soluble substances. In contrast, Olive Cake lipids did not favour the sorption of the more hydrophobic herbicides as indicated by the fact that the sorbed amount increased 30–40% when this fraction was removed. No significant ( P > 0.05) differences in K oc values were found in soils amended with compost and vermicompost in the course of the progressive removal of the different organic fractions, indicating triazine sorption was related more with the total amount of organic matter than with its chemical composition.
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compost and vermicompost of Olive Cake to bioremediate triazines contaminated soil
Science of The Total Environment, 2009Co-Authors: Laura Delgadomoreno, Aranzazu PenaAbstract:The use of organic amendments to bioremediate potential organic pollutants of soil and water has become an increasingly relevant issue in the last years. This strategy has been applied to four triazine herbicides in a typical calcareous agricultural soil of the Mediterranean area. The soil was amended with Olive Cake, compost and vermicompost of Olive Cake at rates four times higher than the agronomic dose in order to stimulate biodegradation of simazine, terbuthylazine, cyanazine and prometryn, added in a mixture to the soils. Degradation studies were carried out in sterile and microbially active soil to evaluate the effect of the chemical and biological degradation of triazines. The residual herbicide concentrations at the end of the degradation assay showed no significant differences between non amended and amended soil. However, the addition of compost and vermicompost enhanced the biological degradation rate of triazines during the first week of incubation, with half-lives ranging form 5 to 18 days for the amended soils, whilst negligible degradation occurred in non-amended soil during this period. In contrast, Olive Cake did not significantly modify the degradation of triazines in spite that the addition of this amendment to soil resulted in the highest dehidrogenase activity values. In all the substrates, degradation of cyanazine and prometryn was faster (between 1.5 and two times higher) than those of terbuthylazine and simazine, without significant relationship with sorption parameters. The first order kinetic equation satisfactorily explained the experimental data for all triazines. A biphasic model, such as that proposed by Hoerl, was better to predict the very rapid triazines decay during the first week of incubation in soil amended with compost and vermicompost.
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sorption desorption behaviour of sulfonylurea herbicides as affected by the addition of fresh and composted Olive Cake to soil
Weed Research, 2008Co-Authors: Laura Delgadomoreno, Aranzazu PenaAbstract:The Olive industry generates residues which can be applied as amendments to soils in their original form (Olive Cake) or after composting or vermicomposting processes. The addition, fresh or incubated, of these amendments to soil and of their different organic fractions was studied in relation to the sorption/desorption of three sulfonylurea herbicides, bensulfuron-methyl, chlorsulfuron and prosulfuron. Herbicide sorption was low or very low, slightly promoted by the addition of the agricultural by-products, especially Olive Cake, and mainly affected by pH of the soil solution, with the organic carbon content having no significant effect on herbicide retention. Desorption was only reduced when fresh Olive Cake was added. The incubation of soil and amendments for 3 months did not modify herbicide sorption, but made desorption reversible except for Olive Cake. The transformation of the organic matter of the amendments due to humification and maturity processes are likely to be responsible for this behaviour. Different organic fractions were removed to assess the influence of each fraction on sulfonylurea sorption. Only the removal of all studied organic fractions increased herbicide sorption, revealing the role of humin and mineral fractions in this process. Therefore, the use of organic amendments is not useful for reducing the risk of movement of ionisable molecules in soil.
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Sorption/desorption behaviour of sulfonylurea herbicides as affected by the addition of fresh and composted Olive Cake to soil
Weed Research, 2008Co-Authors: Laura Delgado-moreno, Aranzazu PenaAbstract:The Olive industry generates residues which can be applied as amendments to soils in their original form (Olive Cake) or after composting or vermicomposting processes. The addition, fresh or incubated, of these amendments to soil and of their different organic fractions was studied in relation to the sorption/desorption of three sulfonylurea herbicides, bensulfuron-methyl, chlorsulfuron and prosulfuron. Herbicide sorption was low or very low, slightly promoted by the addition of the agricultural by-products, especially Olive Cake, and mainly affected by pH of the soil solution, with the organic carbon content having no significant effect on herbicide retention. Desorption was only reduced when fresh Olive Cake was added. The incubation of soil and amendments for 3 months did not modify herbicide sorption, but made desorption reversible except for Olive Cake. The transformation of the organic matter of the amendments due to humification and maturity processes are likely to be responsible for this behaviour. Different organic fractions were removed to assess the influence of each fraction on sulfonylurea sorption. Only the removal of all studied organic fractions increased herbicide sorption, revealing the role of humin and mineral fractions in this process. Therefore, the use of organic amendments is not useful for reducing the risk of movement of ionisable molecules in soil.
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assessment of Olive Cake as soil amendment for the controlled release of triazine herbicides
Science of The Total Environment, 2007Co-Authors: Laura Delgadomoreno, Lourdes Sanchezmoreno, Aranzazu PenaAbstract:Abstract Organic matter-rich agricultural by-products are being produced in huge quantities and can be applied to soil as a disposal strategy. The application of two different rates (2 and 8% w/w) of Olive Cake to a Mediterranean calcareous soil resulted in an increased sorption of four triazine herbicides, which was higher for the more hydrophobic compounds (terbuthylazine and prometryn) and lower for the more polar ones (simazine and cyanazine). However, when the sorption coefficients were normalised to the total soil organic carbon (Koc), the results did not significantly differ between simazine and cyanazine which is an indication that the Olive Cake did not exert different sorption capacity for both compounds. On the contrary, Koc values for terbuthylazine and prometryn increased in the amended soils. Our results from experiments using mixtures of several pesticides suggest that competition for sorption sites resulted in a decrease of herbicide sorption. Desorption was hysteretical both for the amended and unamended soils, but the addition of Olive Cake at the highest dose diminished desorption of most of the herbicides. In conclusion, the addition of Olive Cake behaves as a promising method for reducing the risk of groundwater pollution by pesticides.
Laura Delgadomoreno - One of the best experts on this subject based on the ideXlab platform.
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contribution by different organic fractions to triazines sorption in calcaric regosol amended with raw and biotransformed Olive Cake
Journal of Hazardous Materials, 2010Co-Authors: Laura Delgadomoreno, Aranzazu Pena, G AlmenbdrosAbstract:Abstract A soil, Olive Cake, compost and vermicompost of Olive Cake, were subjected to sequential laboratory extraction to progressively remove water-soluble, lipid and alkali-soluble (humic-type) fractions. Sorption experiments with triazines were carried out with non-amended and amended soil and with soil residues in the intermediate stages during the laboratory removal of the different organic fractions. Herbicide sorption in soil amended with Olive Cake was between two and three times higher than sorption in composted substrates. In non-amended soil, the removal of humic and fulvic acids led to a decrease of triazines sorption indicating the importance of these fractions in the sorption of these pesticides. The greater triazines sorption in soil amended with Olive Cake could be associated with the high concentration of water-soluble substances. In contrast, Olive Cake lipids did not favour the sorption of the more hydrophobic herbicides as indicated by the fact that the sorbed amount increased 30–40% when this fraction was removed. No significant ( P > 0.05) differences in K oc values were found in soils amended with compost and vermicompost in the course of the progressive removal of the different organic fractions, indicating triazine sorption was related more with the total amount of organic matter than with its chemical composition.
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compost and vermicompost of Olive Cake to bioremediate triazines contaminated soil
Science of The Total Environment, 2009Co-Authors: Laura Delgadomoreno, Aranzazu PenaAbstract:The use of organic amendments to bioremediate potential organic pollutants of soil and water has become an increasingly relevant issue in the last years. This strategy has been applied to four triazine herbicides in a typical calcareous agricultural soil of the Mediterranean area. The soil was amended with Olive Cake, compost and vermicompost of Olive Cake at rates four times higher than the agronomic dose in order to stimulate biodegradation of simazine, terbuthylazine, cyanazine and prometryn, added in a mixture to the soils. Degradation studies were carried out in sterile and microbially active soil to evaluate the effect of the chemical and biological degradation of triazines. The residual herbicide concentrations at the end of the degradation assay showed no significant differences between non amended and amended soil. However, the addition of compost and vermicompost enhanced the biological degradation rate of triazines during the first week of incubation, with half-lives ranging form 5 to 18 days for the amended soils, whilst negligible degradation occurred in non-amended soil during this period. In contrast, Olive Cake did not significantly modify the degradation of triazines in spite that the addition of this amendment to soil resulted in the highest dehidrogenase activity values. In all the substrates, degradation of cyanazine and prometryn was faster (between 1.5 and two times higher) than those of terbuthylazine and simazine, without significant relationship with sorption parameters. The first order kinetic equation satisfactorily explained the experimental data for all triazines. A biphasic model, such as that proposed by Hoerl, was better to predict the very rapid triazines decay during the first week of incubation in soil amended with compost and vermicompost.
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sorption desorption behaviour of sulfonylurea herbicides as affected by the addition of fresh and composted Olive Cake to soil
Weed Research, 2008Co-Authors: Laura Delgadomoreno, Aranzazu PenaAbstract:The Olive industry generates residues which can be applied as amendments to soils in their original form (Olive Cake) or after composting or vermicomposting processes. The addition, fresh or incubated, of these amendments to soil and of their different organic fractions was studied in relation to the sorption/desorption of three sulfonylurea herbicides, bensulfuron-methyl, chlorsulfuron and prosulfuron. Herbicide sorption was low or very low, slightly promoted by the addition of the agricultural by-products, especially Olive Cake, and mainly affected by pH of the soil solution, with the organic carbon content having no significant effect on herbicide retention. Desorption was only reduced when fresh Olive Cake was added. The incubation of soil and amendments for 3 months did not modify herbicide sorption, but made desorption reversible except for Olive Cake. The transformation of the organic matter of the amendments due to humification and maturity processes are likely to be responsible for this behaviour. Different organic fractions were removed to assess the influence of each fraction on sulfonylurea sorption. Only the removal of all studied organic fractions increased herbicide sorption, revealing the role of humin and mineral fractions in this process. Therefore, the use of organic amendments is not useful for reducing the risk of movement of ionisable molecules in soil.
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assessment of Olive Cake as soil amendment for the controlled release of triazine herbicides
Science of The Total Environment, 2007Co-Authors: Laura Delgadomoreno, Lourdes Sanchezmoreno, Aranzazu PenaAbstract:Abstract Organic matter-rich agricultural by-products are being produced in huge quantities and can be applied to soil as a disposal strategy. The application of two different rates (2 and 8% w/w) of Olive Cake to a Mediterranean calcareous soil resulted in an increased sorption of four triazine herbicides, which was higher for the more hydrophobic compounds (terbuthylazine and prometryn) and lower for the more polar ones (simazine and cyanazine). However, when the sorption coefficients were normalised to the total soil organic carbon (Koc), the results did not significantly differ between simazine and cyanazine which is an indication that the Olive Cake did not exert different sorption capacity for both compounds. On the contrary, Koc values for terbuthylazine and prometryn increased in the amended soils. Our results from experiments using mixtures of several pesticides suggest that competition for sorption sites resulted in a decrease of herbicide sorption. Desorption was hysteretical both for the amended and unamended soils, but the addition of Olive Cake at the highest dose diminished desorption of most of the herbicides. In conclusion, the addition of Olive Cake behaves as a promising method for reducing the risk of groundwater pollution by pesticides.
G. Martinez - One of the best experts on this subject based on the ideXlab platform.
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reduction of tars by dolomite cracking during two stage gasification of Olive Cake
Biomass & Bioenergy, 2011Co-Authors: J. F. González, José M. Encinar, G. Engo, S. Roman, G. MartinezAbstract:Abstract The effective implementation of biomass gasification has to overcome some difficulties such as the minimization of tars. On the other hand, with a proper design of experimental conditions, biomass gasification can be directed towards the production of hydrogen. The aim of the present study was to investigate the use of dolomite as catalyst to improve tar removal and hydrogen production by a two-stage steam gasification process, using Olive Cake as raw material. Fixing the Olive Cake gasification conditions on the first reactor (900 °C, steam flow rate of 190 mg min −1 , O 2 flow rate of 7.5 cm 3 min −1 ), the cracking of tars was prompted by: a) steam gasification (steam flow rate in the range 40–190 mg min −1 ) at 1000 °C, b) catalytic gasification, using dolomite (5% wt.). It was found that increasing steam flow rate up to 110 mg min −1 involves an increase in hydrogen fraction due to the enhancement of water gas and water gas shift reactions. Also, the influence of dolomite was studied at 800 and 900 °C in a second reactor, finding better results at 800 °C, which gave an hydrogen fraction of 0.51.
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Reduction of tars by dolomite cracking during two-stage gasification of Olive Cake
Biomass and Bioenergy, 2011Co-Authors: J. F. González, José M. Encinar, G. Engo, S. Roman, G. MartinezAbstract:The effective implementation of biomass gasification has to overcome some difficulties such as the minimization of tars. On the other hand, with a proper design of experimental conditions, biomass gasification can be directed towards the production of hydrogen. The aim of the present study was to investigate the use of dolomite as catalyst to improve tar removal and hydrogen production by a two-stage steam gasification process, using Olive Cake as raw material. Fixing the Olive Cake gasification conditions on the first reactor (900 °C, steam flow rate of 190 mg min-1, O2flow rate of 7.5 cm3min-1), the cracking of tars was prompted by: a) steam gasification (steam flow rate in the range 40-190 mg min-1) at 1000 °C, b) catalytic gasification, using dolomite (5% wt.). It was found that increasing steam flow rate up to 110 mg min-1involves an increase in hydrogen fraction due to the enhancement of water gas and water gas shift reactions. Also, the influence of dolomite was studied at 800 and 900 °C in a second reactor, finding better results at 800 °C, which gave an hydrogen fraction of 0.51. © 2011 Elsevier Ltd.
Rogelio Nogales - One of the best experts on this subject based on the ideXlab platform.
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enzyme activities and chemical changes in wet Olive Cake after treatment with pleurotus ostreatus or eisenia fetida
Biodegradation, 2006Co-Authors: M Saavedra, Emilio Benitez, Celia Cifuentes, Rogelio NogalesAbstract:A laboratory experiment was conducted to evaluate the enzyme activities and chemical changes recorded in a recalcitrant phenolic-rich waste after treatment with Pleurotus ostreatus or Eisenia fetida. The waste used was wet Olive Cake (alperujo in Spanish), a waste produced in huge amounts by the Olive oil industry. Both P. ostreatus and E. fetida were very effective in removing phenolic compounds, the initial concentration in the wet Olive Cake being reduced in both cases by around 90%. Laccase and manganese peroxidase activities were measured in the growth medium of P. ostreatus, and catechol 2,3 dioxygenase activity was only detected in the waste treated with Eisenia; these could be the main factors responsible for the oxidation of phenolic compounds. Increases of dehydrogenase and β-glucosidase activities were detected in the degraded wet Olive Cake by fungi or earthworms. In comparison with the natural wet Olive Cake, the degraded products had lower total organic carbon and humic acid contents but were rich in nitrogen and other nutrients, having lower C:N ratios. In addition, the toxicity of the wet Olive Cake against the seeds of Lepidium sativum significantly decreased after degradation. The low toxicity as well as moderate stability and maturity recorded in the wet Olive Cake treated with P. ostreatus or E. fetida imply that these products could be used as soil amendments.
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nitrogen and carbon mineralization in soil of vermi composted and unprocessed dry Olive Cake orujo seco produced from two stage centrifugation for Olive oil extraction
Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes, 1999Co-Authors: R B Thompson, Rogelio NogalesAbstract:Abstract A laboratory‐based incubation study was conducted to examine N mineralization/immobilization and C mineralization of both vermi‐composted and unprocessed dry Olive Cake when added to soil. Cattle manure and a soil‐only treatment were also examined. The organic amendments were mixed with soil at rates to add 1.5 times the soil C (soil C: 6.1 g/kg). The incubations were conducted at 28°C, and were sampled at intervals of 1, 7, 14, 28, 49, 70 and 91 days for the analysis of soil NH4 +‐N and NO3 ‐‐N, and soil respiration. The C to N ratios of the unprocessed Olive Cake, vermi‐composted Olive Cake and manure were 42, 29 and 11, respectively. Both the unprocessed Olive Cake and vermi‐composted Olive Cake immobilized soil N throughout the 91 days of the study. The cattle manure mineralized an appreciable amount of N during the study. The prolonged immobilization of soil N by the vermi‐composted Olive Cake was attributed to the C to N ratio of 29 and to the recalcitrant nature of its C and N composition....
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Nitrogen and carbon mineralization in soil of vermi‐composted and unprocessed dry Olive Cake ("Orujo Seco") produced from two‐stage centrifugation for Olive oil extraction
Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes, 1999Co-Authors: R B Thompson, Rogelio NogalesAbstract:Abstract A laboratory‐based incubation study was conducted to examine N mineralization/immobilization and C mineralization of both vermi‐composted and unprocessed dry Olive Cake when added to soil. Cattle manure and a soil‐only treatment were also examined. The organic amendments were mixed with soil at rates to add 1.5 times the soil C (soil C: 6.1 g/kg). The incubations were conducted at 28°C, and were sampled at intervals of 1, 7, 14, 28, 49, 70 and 91 days for the analysis of soil NH4 +‐N and NO3 ‐‐N, and soil respiration. The C to N ratios of the unprocessed Olive Cake, vermi‐composted Olive Cake and manure were 42, 29 and 11, respectively. Both the unprocessed Olive Cake and vermi‐composted Olive Cake immobilized soil N throughout the 91 days of the study. The cattle manure mineralized an appreciable amount of N during the study. The prolonged immobilization of soil N by the vermi‐composted Olive Cake was attributed to the C to N ratio of 29 and to the recalcitrant nature of its C and N composition....
J. F. González - One of the best experts on this subject based on the ideXlab platform.
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reduction of tars by dolomite cracking during two stage gasification of Olive Cake
Biomass & Bioenergy, 2011Co-Authors: J. F. González, José M. Encinar, G. Engo, S. Roman, G. MartinezAbstract:Abstract The effective implementation of biomass gasification has to overcome some difficulties such as the minimization of tars. On the other hand, with a proper design of experimental conditions, biomass gasification can be directed towards the production of hydrogen. The aim of the present study was to investigate the use of dolomite as catalyst to improve tar removal and hydrogen production by a two-stage steam gasification process, using Olive Cake as raw material. Fixing the Olive Cake gasification conditions on the first reactor (900 °C, steam flow rate of 190 mg min −1 , O 2 flow rate of 7.5 cm 3 min −1 ), the cracking of tars was prompted by: a) steam gasification (steam flow rate in the range 40–190 mg min −1 ) at 1000 °C, b) catalytic gasification, using dolomite (5% wt.). It was found that increasing steam flow rate up to 110 mg min −1 involves an increase in hydrogen fraction due to the enhancement of water gas and water gas shift reactions. Also, the influence of dolomite was studied at 800 and 900 °C in a second reactor, finding better results at 800 °C, which gave an hydrogen fraction of 0.51.
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Reduction of tars by dolomite cracking during two-stage gasification of Olive Cake
Biomass and Bioenergy, 2011Co-Authors: J. F. González, José M. Encinar, G. Engo, S. Roman, G. MartinezAbstract:The effective implementation of biomass gasification has to overcome some difficulties such as the minimization of tars. On the other hand, with a proper design of experimental conditions, biomass gasification can be directed towards the production of hydrogen. The aim of the present study was to investigate the use of dolomite as catalyst to improve tar removal and hydrogen production by a two-stage steam gasification process, using Olive Cake as raw material. Fixing the Olive Cake gasification conditions on the first reactor (900 °C, steam flow rate of 190 mg min-1, O2flow rate of 7.5 cm3min-1), the cracking of tars was prompted by: a) steam gasification (steam flow rate in the range 40-190 mg min-1) at 1000 °C, b) catalytic gasification, using dolomite (5% wt.). It was found that increasing steam flow rate up to 110 mg min-1involves an increase in hydrogen fraction due to the enhancement of water gas and water gas shift reactions. Also, the influence of dolomite was studied at 800 and 900 °C in a second reactor, finding better results at 800 °C, which gave an hydrogen fraction of 0.51. © 2011 Elsevier Ltd.
