Browsing by Autor "Carlo Vandecasteele"

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CONTAMINACION DEL AGUA Y SUBSUELO POR EL USO DEL FLUROXIPIR METILHEPTIL ESTER EN CULTIVOS DE SOYA EN LA LOCALIDAD DE CHANÉ EN EL DEPARTAMENTO DE SANTA CRUZ
(Universidad Autónoma del Estado de México, 2005) Paul E. Vargas; W. de Groot; Carlo Vandecasteele
"Starane® es un producto herbicida muy utilizado en el cultivo de soya, su componente activo es fluroxipir metilheptil éster (FMHE). Se colectaron muestras de suelo de Santa Cruz y Cochabamba. Los valores de Kd y Koc obtenidos para el FMHE fueron 8 ml g-1 y 401 ml g-1. Los ensayos de infiltración con 1,74 veces la dosis de FMHE aplicada en campo presentaron una recuperación de menos del 1% de FMHE. Solo suelos con abundancia de material grueso presentaron FMHE en sus respectivos infiltrados. Altos contenidos de materia orgánica y sales se asociaron con una mayor y menor sorción de FMHE en el suelo, respectivamente. FMHE fue detectado en cuatro ríos y un pozo poco profundo de Santa Cruz."
DGT-measured fluxes explain the chloride-enhanced cadmium uptake by plants at low but not at high Cd supply
(Springer Science+Business Media, 2008) Carla Oporto; Erik Smolders; Fien Degryse; Liesbeth Verheyen; Carlo Vandecasteele
Diversidad acuática en la zona de influencia de un campo de gas y petróleo en la provincia Carrasco (Cochabamba, Bolivia)
(2000) Franklin Horacio Lozada Maldonado; Paul Van Damme; R. Sanabria; Fabio Araya Carvajal; Carlo Vandecasteele; Joel Rojas Acuña
AQUATIC DIVERSITY IN A RIVER ADJACENT TO A GAS AND PETROLEUM EXPLOITATION SITE IN THE PROVINCE CARRASCO (COCHABAMBA, BOLIVIA) El rio Izozog (Carrasco, departamento de Cochabamba) recibe desechos liquidos difusos de la actividad petrolera desarrollada en la zona. La diversidad acuatica en este rio fue estudiada, y los impactos posibles de contaminacion por los derrames sobre la diversidad acuatica fueron investigados. El efecto sobre la calidad del agua es poco apreciable tanto en epoca de estiaje como en periodo de lluvias: unicamente en la zona de muestreo rio abajo de las descargas, se detecto un incremento en conductividad, D00 (Demanda Quimica de Oxigeno) e Hidrocarburos Totales. Macroinvertebrados bentonicos fueron muestreados con un surber sampler en rapidos y con una draga Van Veen en pozas. La comunidad de peces fue muestreada con un equipo portatil de pesca electrica (Smith-Rooth) en rapidos. Los macroinvertebrados bentonicos del rio Izozog pertenecen a 19 familias. Los 497 peces que fueron capturados pertenecen a 17 taxas. Characidae y Loricariidae fueron las familias mejor representadas tanto en terminos de numero de especies como en numero de individuos. B imii>8cto de la contaminacion se evidencio sobre las comunidades de bentos rio abajo del area de contaminacion difusa durante la epoca seca; sin embargo, en epoca de lluvias el efecto sobre el bentos no fue significativo. No hubo un impacto detectable de la contaminacion sobre los peces. Empero, fue dificil discriminar entre variaciones naturales y cambios inducidos por contaminacion. Una discusion sobre estrategias de muestreo para detectar impactos ambientales esta incluida. Palabras clave: Contaminacion, petroleo, bentos, peces, rio Izozog, Cochabamba, Bolivia. ABSTRACT The Izozog River receives contaminated water from a number of non-point sources, generated by oil exploration activities in the Carrasco Province of the State of Cochabamba. The aquatic diversity in this river was studied and possible impacts of oil contamination on aquatic diversity were assessed. In general, the effect on water quality was minor in both the rainy and dry season. Only in samples collected downriver from the pollution source, was an increase in conductivity, 00D (Chemical Oxygen Oemand), and Total Hydrocarbon Concentration observed. In rapids, the benthic macroinvertebrates were sampled with a surber sampler while in pools, a Van Veen sampler was used. In rapids, the fish community was sampled with a portable electrical fishing apparatus (Smith-Root). The benthic macroinvertebrates recorded in the Izozog River belonged to 19 different families. A total of 497 fish, belonging to 17 different taxa, were collected. In terms of species number and number of individuals, Characidae and Loricariidae were most numerous. The impact of the contamination on the benthic community in the sample point immediately downstream from the non-point contamination sources was observed during the dry season, whereas the impact on the fish community was never detectable. The overall impact during the rainy season was small. However; it was difficult to distinguish between natural variation and contamination-induced changes in community structure. A discussion on sample strategies to detect environmental impacts of petroleum contamination is also presented. Key words: Contamination, petroleum, benthos, bio-indication, river Izozog, Cochabamba, Bolivia.
Efficiencies of available organic mixtures for the biological treatment of highly acidic-sulphate rich drainage of the San Jose mine, Bolivia
(Taylor & Francis, 2019) Carla Oporto; Gabriela Baya; Carlo Vandecasteele
The environmental contamination due to mining activities in the Andean region of Bolivia is a serious concern, as it leads to highly acidic (pH 2.4) acid mine drainage (AMD), severely polluted by sulfate (>12,000 mg L-1). Passive bioreactors entailing biological sulfate reduction and removal of metals through sulfide precipitation have been recognized as a promising biotechnology. The reactivity of mixtures containing locally available substrates: sheep manure, compost and straw, was assessed through batch experiments conducted with a synthetic solution simulating the composition of AMD from San José mine (Oruro). The removal of sulfate and metals was successful in all reactors, at the end of the experiment (56 days) sulfate concentrations dropped to 1378-2081 mg L-1, corresponding to a removal efficiency between 84% and 89%, while average removal for Fe, Zn, Pb, and Cd were 99.8%, 98.5%, 94.7%, 98.6%, respectively. The sulfate and metal removal showed three phases. In the first phase, the removal was independent of the organic composition and attributable to pH-controlled mechanisms i.e. adsorption, precipitation of oxy(hydroxides) and co-precipitation. During the second phase, sulfate and metals concentrations remained rather constant; while in the third phase, the removal was affected by the organic matter composition. Sulfate removal rate attained the highest values (227-243 mg L-1 d-1) in the third phase, and it was attributable to biological reduction with not sulfate limitation. The depletion of nutrients rather than the sulfate availability may have limited the sulfate removal at the end of the experiment.
EL IMPACTO DE CONTAMINACIÓN POR HIDROCARBUROS SOBRE LA CALIDAD DE AGUAS Y SOBRE MACROINVERTEBRADOS BENTÓNICOS DEL RIO HONDO (CARRASCO, COCHABAMBA, BOLVIA)
(2000) Francisco Maldonado; PA Van Damme; Joel Rojas Acuña; R. Sanabria; Claude Creemers; Carlo Vandecasteele
THE IMPACT OF PETROLEUM CONTAMINATION ON THE WATER AUALITY AND THE BENTHIC MACROINVERTEBRATES OF RIVER HONDO (CARRASCO, COCHABAMBA, BOLIVIA) El impacto que ejercen las descargas de residuos liquidos y solidos petroleros sobre los ecosistemas acuaticos de agua dulce es muy poco conocido. Este estudio investiga el impacto ambiental causado por la actividad petrolera en la provincia Carrasco del Departamento de Cochabamba (Bolivia). El estudio de caso es un derrame continuo de desechos liquidos con hidrocarburos, que afecta a al calidad de aguas superficiales y a la comunidad de macroinvertebrados bentonicos en el rio Hondo, un rio pequeno de bajo caudal, en dos periodos, epoca seca y epoca de Iluvias. El agua en el punto de descarga presento valores elevados de hidrocarburos totales. En la torrentera que recibe los desechos y en los tramos mas contaminados del rio Hondo no se encontro ningun organismo. La concentracion de los contaminantes disminuyo notablemente a lo largo del rio Hondo, principalmente por efecto de dilucion. En los tramos rio abajo, con contaminacion intermedia, se observo poco impacto sobre la diversidad de macroinvertebrados acuaticos, pero si sobre la densidad y sobre la estructura tropica de las comunidades. Los efectos de contaminacion fueron mas severos en epoca de estiaje que en epoca de lluvias, probablemente debido a una mayor dilucion en la ultima epoca. Palabras clave: Contaminacion, petroleo, bentos, bio-indicaccion, rio Hondo, Cochabamba, Bolivia. ABSTRACT The environmental impact of solid and liquid petroleum contamination on aquatic freshwater systems is poorly understood. The impact of small, continuous petroleum spills was studied in the province Carrasco in the department of Cochabamba (Bolivia) in the Hondo rivet; a river with small discharge. The impact of hydrocarbon waste on river water quality and on the macroinvertebrate community structure was studied during two periods, the dry season and the rainy season. In the small brook, which received hydrocarbon containing liquid waste and in the upper parts of Hondo rivet; no organisms were recorded as a result of hydrocarbon contamination. There was a downstream decrease of contamination levels due to dilution effects. In downstream segments with intermediate contamination levels, the impact of petroleum contamination on macroinvertebrate diversity was small, whereas the impact on the density of macroinvertebrates and on the trophic structure of the benthic communities was significant in both seasons. The effects of contamination were always more severe in the dry season than in the rainy season, probably because of dilution effect during the rainy season. Key words: Contamination, petroleum, benthos, bio-indication, Hondo river, Cochabamba, Bolivia.
Experimental study and modelling of Cr (VI) removal from wastewater using Lemna minor
(Elsevier BV, 2006) Carla Oporto; Omar Arce; Eric Van den Broeck; Bart Van der Bruggen; Carlo Vandecasteele
Identifying the cause of soil cadmium contamination with Monte Carlo mass balance modelling: a case study from Potosi, Bolivia
(Taylor & Francis, 2011) Carla Oporto; Erik Smolders; Carlo Vandecasteele
The Chayanta river in Potosi, Bolivia is polluted by present and past mining activities in the districts of Siglo XX and Llallagua. The river water, which is enriched with cadmium (Cd), is used for irrigation in the Quila Quila and Asiruri valleys where the median soil Cd concentration is 20 mg kg(-1), well above the background value of < 0.5 mg kg(-1). The objective of this study was to predict current soil contamination using a retrospective mass balance. Monitoring data were collected on Cd concentrations in irrigation water, irrigation application rates, crop yield and composition, and soil properties including pore water composition. The mass balance was made assuming constant model parameters since the start of upstream mining operations about 85 years ago (1920). The parameter uncertainty was taken into account with a Monte Carlo analysis. The current annual Cd input by irrigation is 800 g ha(-1). The annual output of Cd through removal of the crop harvest and leaching is less than 10 g ha(-1). The predicted soil Cd concentrations after 85 years of contamination (geometric mean: 21.9 mg x kg(-1), 10th and 90th percentile 7.2-65.1 mg kg(-1) respectively) matched the distribution of observed values (geometric mean: 18.6 mg kg(-1); 10th and 90th percentile 4.7-65.9 mg kg(-1) respectively; n = 56). This study confirmed that irrigation water is the prime source of soil Cd enrichment in that area. The Monte Carlo analysis is a convenient way of including parameter uncertainty in mass balance modelling and of estimating spatial variability of the contamination.
Influence of Mining Activities in the North of Potosi, Bolivia on the Water Quality of the Chayanta River, and its Consequences
(Springer Science+Business Media, 2006) José Alejandro Romero Rojas; Carlo Vandecasteele
Metales (Cr, Pb y Zn) en sedimentos y quironómidos del río Rocha
(2000) Ana Romero; Carlo Vandecasteele; Herman Cooreman