Dada la complejidad de la evaluacion integral de los recursos hidricos es necesario que los estud... more Dada la complejidad de la evaluacion integral de los recursos hidricos es necesario que los estudios hidrogeologicos a nivel de cuenca se enriquezcan con el analisis regional, por ejemplo a traves de la comparacion entre cuencas de una region. Se planteo como objetivo del trabajo elaborar una propuesta para el estudio comparativo del recurso hidrico subterraneo y analizarla a traves del ejemplo de caso de las cuencas de los arroyos Langueyu y Del Azul. Los aspectos definidos para la comparacion fueron: litologia, hidrodinamica, hidroquimica e influencia antropica. Se consideraron mediciones de niveles freaticos y analisis fisicoquimicos en redes de monitoreo del agua subterranea; se analizaron los impactos potenciales al sistema segun las caracteristicas del medio fisico y las actividades antropicas. De acuerdo a los resultados, en ambas cuencas la disponibilidad de agua subterranea esta dada por dos ambientes hidrogeologicos (fisurado y poroso); el modelo conceptual hidrodinamico e...
VIII Congreso Argentino de Hidrogeología y VI Seminario Latinoamericano sobre Termas Actuales de la Hidrología Subterránea (La Plata, 17 al 20 de septiembre de 2013), 2013
VIII Congreso Argentino de Hidrogeología y VI Seminario Latinoamericano sobre Termas Actuales de la Hidrología Subterránea (La Plata, 17 al 20 de septiembre de 2013), 2013
The sensitivity of adsorptive cathodic stripping voltammetry (CSV) to vanadium is much improved b... more The sensitivity of adsorptive cathodic stripping voltammetry (CSV) to vanadium is much improved by inclusion of a catalytic effect. The deposition step is based on the adsorptive accumulation of complex species with catechol on a hanging mercury drop electrode. The reduction current of the adsorbed complex is catalytically enhanced by addition of bromate. This effect is utilised to develop a sensitive method to determine vanadium in natural waters including sea water. Optimum response was obtained at pH 6.6 in the presence of XI mM bromate and 0.1 catechol; the deposition potential was -0.1 V and the square-wave modulation (50 Hz) was used. The limit of detection was 0.07 nM vanadium using a deposition time of 120 s and 0.6 nM at a deposition time of 15 s. Key words: Catalytic methods; Stripping voltammetry; Sea water; Vanadium; Waters 1. Introduct.lon natural waters, most
Photobioreactors for wastewater treatment coupled with nutrient recovery from the biomass is a pr... more Photobioreactors for wastewater treatment coupled with nutrient recovery from the biomass is a promising biorefinery platform but requires working with microalgae-bacteria consortia. This work compares the effect that hydrolysis time and different enzymes have on the solubilization and recovery of components from microalgae-bacteria grown in piggery wastewater and microalgae grown in synthetic media by enzymatic hydrolysis. Higher carbohydrate solubilizations were obtained from microalgae-bacteria than from pure microalgae (38.5% vs. 27% Celluclast, 5 h), as expected from the SEM images. Proteases solubilized xylose remarkably well, but xylose recovery was negligible in all experiments. Alcalase hydrolysis (5 h) provided the highest peptide recovery from both biomasses (≈34%), but the peptide sizes were lower than 10 kDa. Low peptide recoveries (<20%) but larger peptide sizes (up to 135 kDa) were obtained with Protamex. Pure microalgae resulted in remarkably higher losses, but similar amino acid profiles and peptide sizes were obtained from both biomasses.
This work represents a comparative uptake study of the toxic elements arsenic, boron, copper, man... more This work represents a comparative uptake study of the toxic elements arsenic, boron, copper, manganese and zinc in monometallic and multimetallic solutions by four green microalgae species (Chlamydomonas reinhardtii, Chlorella vulgaris, Scenedesmus almeriensis and an indigenous Chlorophyceae spp.), evaluating the effect of pH and contact time. Maximum removal efficiencies for each toxic element were 99.4% for Mn (C. vulgaris, pH 7.0, 3 h), 91.9% for Zn (Chlorophyceae spp., pH 5.5, 3 h), 88% for Cu (Chlorophyceae spp., pH 7.0, 10 min), 40.7% for As (S. almeriensis, pH 9.5, 3 h) and 38.6% for B (S. almeriensis, pH 5.5, 10 min). B removal efficiencies decreased remarkably in multimetallic solutions (down to 0.2% in C. reinhardtii), except for Chlorophyceae spp., the only species isolated from a polluted environment. FTIR spectra shown the highest interactions for As (1150-1300 cm) and Cu (3300, 1741, 1535, 1350-1400 cm). Results confirm microalgae biomass as a potential biosorbent for...
Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported a... more Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported along the southern edge of the Cenozoic Duero Basin (CDB) near its contact with the Spanish Central System (SCS). In this area, spatial variability of arsenic is high, peaking at 241μg/L. Forty-seven percent of samples collected contained arsenic above the maximum allowable concentration for drinking water (10μg/L). Correlations of As with other hydrochemical variables were investigated using multivariate statistical analysis (Hierarchical Cluster Analysis, HCA and Principal Component Analysis, PCA). It was found that As, V, Cr and pH are closely related and that there were also close correlations with temperature and Na(+). The highest concentrations of arsenic and other associated Potentially Toxic Geogenic Trace Elements (PTGTE) are linked to alkaline NaHCO3 waters (pH≈9), moderate oxic conditions and temperatures of around 18°C-19°C. The most plausible hypothesis to explain the high a...
Extensionismo, Innovación y Transferencia Tecnológica, 2021
Los ríos tienen un rol importante en el desarrollo de múltiples procesos que ocurren sobre la sup... more Los ríos tienen un rol importante en el desarrollo de múltiples procesos que ocurren sobre la superficie terrestre. A largo de su recorrido, producen reacciones que afectan a su entorno. Así, la interacción del agua de los ríos con el terreno que atraviesan, definen en gran parte las características hidroquímicas y geoquímicas de los cuerpos de agua, que hacen posible o no la vida.En este trabajo se ha muestreado espacial y temporalmente las variables físicas y químicas de las aguas del río Negro (Provincia del Chaco, Argentina), a fin de evaluar las fuentes que producen sus variaciones: precipitaciones, suelos e influencia antrópica. Se ha evaluado además la influencia de la hidroquímica sobre el comportamiento de los sólidos suspendidos. De esta forma se espera contribuir con el conocimiento sobre la dinámica de las aguas de éste río de llanura y echar luz sobre el efecto de la actividad antrópica sobre ella.
The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, P... more The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, Zn, Ba, Si and Sr) have been determined in groundwater samples from the Langueyu creek basin, in the Argentina Pampean plain. This research aims to establish the baseline concentration and geographical distribution of trace elements in this basin. This aim has particular interest to public health in the city of Tandil where groundwater is the principal source of water for human supply. The baseline concentrations of elements in the Langueyu creek basin are in good agreement with published data from other locations of the Pampean aquifer. The arsenic limit of 10mg/l, established as provisional limit by the World Health Organization (WHO), was exceeded in 78% of the sampled wells, with As concentration increasing in the direction of groundwater flow. Concentrations of B, Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn regulated by the Argentinian Food Code (CAA) do not exceed the maximum limit for...
Extensionismo, Innovación y Transferencia Tecnológica, 2018
Con la finalidad de conservar los ambientes fluviales en sus condiciones prístinas, diversas vari... more Con la finalidad de conservar los ambientes fluviales en sus condiciones prístinas, diversas variables deben ser analizadas. Los sedimentos son unas de las variables más importantes dado que influye potencialmente la morfología del paisaje, la química de las aguas y la dinámica biológica de los cursos de agua. El presente trabajo presenta una introducción de fácil interpretación sobre las características de mayor relevancia ambiental de los sedimentos, sus interacciones y su dinámica en áreas de llanura, de tal modo que los científicos que trabajen en ambientes fluviales de llanura puedan tener una primera aproximación para una correcta interpretación ambiental del rol de los sedimentos. Las características aquí mencionadas incluyen clasificación granulométrica, transporte y mineralogía. En las últimas décadas aumentaron las investigaciones sobre estudios orientados a la evaluación de ambientes fluviales con el objeto de mejorar el conocimiento de su estructura y dinámica, para así ...
Dada la complejidad de la evaluacion integral de los recursos hidricos es necesario que los estud... more Dada la complejidad de la evaluacion integral de los recursos hidricos es necesario que los estudios hidrogeologicos a nivel de cuenca se enriquezcan con el analisis regional, por ejemplo a traves de la comparacion entre cuencas de una region. Se planteo como objetivo del trabajo elaborar una propuesta para el estudio comparativo del recurso hidrico subterraneo y analizarla a traves del ejemplo de caso de las cuencas de los arroyos Langueyu y Del Azul. Los aspectos definidos para la comparacion fueron: litologia, hidrodinamica, hidroquimica e influencia antropica. Se consideraron mediciones de niveles freaticos y analisis fisicoquimicos en redes de monitoreo del agua subterranea; se analizaron los impactos potenciales al sistema segun las caracteristicas del medio fisico y las actividades antropicas. De acuerdo a los resultados, en ambas cuencas la disponibilidad de agua subterranea esta dada por dos ambientes hidrogeologicos (fisurado y poroso); el modelo conceptual hidrodinamico e...
VIII Congreso Argentino de Hidrogeología y VI Seminario Latinoamericano sobre Termas Actuales de la Hidrología Subterránea (La Plata, 17 al 20 de septiembre de 2013), 2013
VIII Congreso Argentino de Hidrogeología y VI Seminario Latinoamericano sobre Termas Actuales de la Hidrología Subterránea (La Plata, 17 al 20 de septiembre de 2013), 2013
The sensitivity of adsorptive cathodic stripping voltammetry (CSV) to vanadium is much improved b... more The sensitivity of adsorptive cathodic stripping voltammetry (CSV) to vanadium is much improved by inclusion of a catalytic effect. The deposition step is based on the adsorptive accumulation of complex species with catechol on a hanging mercury drop electrode. The reduction current of the adsorbed complex is catalytically enhanced by addition of bromate. This effect is utilised to develop a sensitive method to determine vanadium in natural waters including sea water. Optimum response was obtained at pH 6.6 in the presence of XI mM bromate and 0.1 catechol; the deposition potential was -0.1 V and the square-wave modulation (50 Hz) was used. The limit of detection was 0.07 nM vanadium using a deposition time of 120 s and 0.6 nM at a deposition time of 15 s. Key words: Catalytic methods; Stripping voltammetry; Sea water; Vanadium; Waters 1. Introduct.lon natural waters, most
Photobioreactors for wastewater treatment coupled with nutrient recovery from the biomass is a pr... more Photobioreactors for wastewater treatment coupled with nutrient recovery from the biomass is a promising biorefinery platform but requires working with microalgae-bacteria consortia. This work compares the effect that hydrolysis time and different enzymes have on the solubilization and recovery of components from microalgae-bacteria grown in piggery wastewater and microalgae grown in synthetic media by enzymatic hydrolysis. Higher carbohydrate solubilizations were obtained from microalgae-bacteria than from pure microalgae (38.5% vs. 27% Celluclast, 5 h), as expected from the SEM images. Proteases solubilized xylose remarkably well, but xylose recovery was negligible in all experiments. Alcalase hydrolysis (5 h) provided the highest peptide recovery from both biomasses (≈34%), but the peptide sizes were lower than 10 kDa. Low peptide recoveries (<20%) but larger peptide sizes (up to 135 kDa) were obtained with Protamex. Pure microalgae resulted in remarkably higher losses, but similar amino acid profiles and peptide sizes were obtained from both biomasses.
This work represents a comparative uptake study of the toxic elements arsenic, boron, copper, man... more This work represents a comparative uptake study of the toxic elements arsenic, boron, copper, manganese and zinc in monometallic and multimetallic solutions by four green microalgae species (Chlamydomonas reinhardtii, Chlorella vulgaris, Scenedesmus almeriensis and an indigenous Chlorophyceae spp.), evaluating the effect of pH and contact time. Maximum removal efficiencies for each toxic element were 99.4% for Mn (C. vulgaris, pH 7.0, 3 h), 91.9% for Zn (Chlorophyceae spp., pH 5.5, 3 h), 88% for Cu (Chlorophyceae spp., pH 7.0, 10 min), 40.7% for As (S. almeriensis, pH 9.5, 3 h) and 38.6% for B (S. almeriensis, pH 5.5, 10 min). B removal efficiencies decreased remarkably in multimetallic solutions (down to 0.2% in C. reinhardtii), except for Chlorophyceae spp., the only species isolated from a polluted environment. FTIR spectra shown the highest interactions for As (1150-1300 cm) and Cu (3300, 1741, 1535, 1350-1400 cm). Results confirm microalgae biomass as a potential biosorbent for...
Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported a... more Naturally occurring arsenic in groundwater exceeding the limit for potability has been reported along the southern edge of the Cenozoic Duero Basin (CDB) near its contact with the Spanish Central System (SCS). In this area, spatial variability of arsenic is high, peaking at 241μg/L. Forty-seven percent of samples collected contained arsenic above the maximum allowable concentration for drinking water (10μg/L). Correlations of As with other hydrochemical variables were investigated using multivariate statistical analysis (Hierarchical Cluster Analysis, HCA and Principal Component Analysis, PCA). It was found that As, V, Cr and pH are closely related and that there were also close correlations with temperature and Na(+). The highest concentrations of arsenic and other associated Potentially Toxic Geogenic Trace Elements (PTGTE) are linked to alkaline NaHCO3 waters (pH≈9), moderate oxic conditions and temperatures of around 18°C-19°C. The most plausible hypothesis to explain the high a...
Extensionismo, Innovación y Transferencia Tecnológica, 2021
Los ríos tienen un rol importante en el desarrollo de múltiples procesos que ocurren sobre la sup... more Los ríos tienen un rol importante en el desarrollo de múltiples procesos que ocurren sobre la superficie terrestre. A largo de su recorrido, producen reacciones que afectan a su entorno. Así, la interacción del agua de los ríos con el terreno que atraviesan, definen en gran parte las características hidroquímicas y geoquímicas de los cuerpos de agua, que hacen posible o no la vida.En este trabajo se ha muestreado espacial y temporalmente las variables físicas y químicas de las aguas del río Negro (Provincia del Chaco, Argentina), a fin de evaluar las fuentes que producen sus variaciones: precipitaciones, suelos e influencia antrópica. Se ha evaluado además la influencia de la hidroquímica sobre el comportamiento de los sólidos suspendidos. De esta forma se espera contribuir con el conocimiento sobre la dinámica de las aguas de éste río de llanura y echar luz sobre el efecto de la actividad antrópica sobre ella.
The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, P... more The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, Zn, Ba, Si and Sr) have been determined in groundwater samples from the Langueyu creek basin, in the Argentina Pampean plain. This research aims to establish the baseline concentration and geographical distribution of trace elements in this basin. This aim has particular interest to public health in the city of Tandil where groundwater is the principal source of water for human supply. The baseline concentrations of elements in the Langueyu creek basin are in good agreement with published data from other locations of the Pampean aquifer. The arsenic limit of 10mg/l, established as provisional limit by the World Health Organization (WHO), was exceeded in 78% of the sampled wells, with As concentration increasing in the direction of groundwater flow. Concentrations of B, Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn regulated by the Argentinian Food Code (CAA) do not exceed the maximum limit for...
Extensionismo, Innovación y Transferencia Tecnológica, 2018
Con la finalidad de conservar los ambientes fluviales en sus condiciones prístinas, diversas vari... more Con la finalidad de conservar los ambientes fluviales en sus condiciones prístinas, diversas variables deben ser analizadas. Los sedimentos son unas de las variables más importantes dado que influye potencialmente la morfología del paisaje, la química de las aguas y la dinámica biológica de los cursos de agua. El presente trabajo presenta una introducción de fácil interpretación sobre las características de mayor relevancia ambiental de los sedimentos, sus interacciones y su dinámica en áreas de llanura, de tal modo que los científicos que trabajen en ambientes fluviales de llanura puedan tener una primera aproximación para una correcta interpretación ambiental del rol de los sedimentos. Las características aquí mencionadas incluyen clasificación granulométrica, transporte y mineralogía. En las últimas décadas aumentaron las investigaciones sobre estudios orientados a la evaluación de ambientes fluviales con el objeto de mejorar el conocimiento de su estructura y dinámica, para así ...
The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, P... more The contents of arsenic (As), fluoride (F) and other trace elements (B, Cd, Cr, Cu, Fe, Mn, Ni, Pb, V, Zn, Ba, Si and Sr) have been determined in groundwater samples from the Langueyú creek basin, in the Argentina Pampean plain. This research aims to establish the baseline concentration and geographical distribution of trace elements in this basin. This aim has particular interest to public health in the Tandil city where groundwater is the principal source of water for human supply. The baseline concentrations of elements in the Langueyú creek basin are in good agreement with published data from other locations of the Pampean aquifer. The As limit of 10μg/L, established as provisional limit by the World Health Organization (WHO), was exceeded in 78% of the sampled wells, with As concentration increasing in the direction of groundwater flow. Concentrations of B, Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn regulated by the Argentinian Food Code (CAA) do not exceed the maximum limit for drinking water, although concentrations of Ni, Zn or Pb peaked up at some wells, probably due to pipeline corrosion. The strong correlation observed between As, F, V, Cr and B has been related to their anionic character at the groundwater natural alkaline pH that is likely associated with similar mobilization (adsorption/desorption) processes. Worst consequences for human health have arisen in areas with the highest As concentration in drinking water. The conclusions of this study contribute to understand the provenance and mobilization processes of some trace elements in groundwater. It enables the decision making regarding public health priorities and technological treatments of water resources in urban and rural areas.
Uploads
Papers by Marisol Vega