Procesos Geoquímicos Superficiales en Iberoamérica

[EN] This volume of the Ibero-American Society of Environmental Physics and Chemistry brings together 31 scientific papers that were presented on the occasion of the II RAGSU, which, for convenience, have been grouped into five sections: Geochemistry of soils and sediments, Geochemistry of aquatic ecosystems, Biogeochemical processes, paleo-geochemical processes and analytical geochemistry. The works produced by different Latin American groups show the excellent scientific level intended to be maintained in these meetings, following state-of-the-art and in total harmony with the significance of the problems to be addressed or the knowledge to be disseminated in the region.[ES] Este volumen de la Sociedad Ibero-Americana de Fisica y Quimica Ambiental, reúne 31 trabajos científicos que fueron presentados en ocasión de la II RAGSU los cuales, por conveniencia, han sido agrupados en cinco secciones: Geoquímica de suelos y sedimentos, Geoquímica de ecosistemas acuáticos, Procesos biogeoquímicos, Procesos paleo-geoquímicos y Geoquímica analítica. Los trabajos, producidos por distintos grupos latinoamericanos, evidencian el excelente nivel científico que se pretende mantener en estas reuniones, acordes con el estado del arte y en total consonancia con la significación de los problemas a atender o los conocimientos a difundir en la región.Peer reviewe

Metales pesados en el riñón del delfín franciscana, Pontoporia blainvillei (Cetácea: Pontoporiidae) y su relación con parámetros biológicos Heavy metals in kidney tissues of Franciscana dolphin, Pontoporia blainvillei (Cetacea: Pontoporiidae), and their relationship with biological parameters

En este estudio se determinó los niveles de metales pesados (Cd, Pb, Zn, Cu, Cr y Ni) en el tejido renal del delfín franciscana, Pontoporia blainvillei, y se estableció la influencia de los parámetros ecológicos y biológicos sobre la bioacumulación de estos elementos. Se analizaron muestras de 38 ejemplares colectados entre 2004 y 2010 en el sur de Buenos Aires, Argentina. La edad de los animales y el estado de madurez sexual se determinaron por métodos histológicos, y los niveles de metales pesados por Espectrofotometría de Absorción Atómica. No se determinaron diferencias significativas para las concentraciones de Zn, Cu y Cd entre ambos sexos. Los niveles de Cd presentaron diferencias según el estado de madurez sexual y se relacionaron positivamente con la longitud, peso corporal y edad. Los niveles de Cd, Cu y Zn resultaron menores a los informados en estudios previos realizados en el norte de Buenos Aires y Uruguay.Heavy metal (Cd, Pb, Zn, Cu, Cr,Ni) concentrations were determined in the kidney tissue of the Franciscana dolphin, Pontoporia blainvillei, and the influence of ecological and biological parameters on the bioaccumulation of these elements was established. Samples from 38 specimens, collected between 2004 and 2010 off southern Buenos Aires, Argentina, were analyzed. Histological methods were used to determine both the age and sexual maturity of the animals. Heavy metal concentrations were measured by atomic absorption spectrophotometry. No significant differences were found by sex for Zn, Cu, and Cd. However, Cd levels differed between maturity stages and were positively related to length, body weight, and age. The Cd, Cu, and Zn levels reported here in were lower than those included in previous studies done off northern Buenos Aires and Uruguay

First records of polycyclic aromatic hydrocarbons and metals in sediments from a shallow lake in the Pampean-Patagonian region (Argentina)

This study evaluated, for the first time, organic and metal contaminants in sediments from Argentinean saline lakes, specifically La Salada shallow lake, a small polymictic lake on the south border of the Pampean region. The concentration of 16 priority polycyclic aromatic hydrocarbons (PAHs) and 8 metals (Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn) was assessed and the ecotoxicological effects of these pollutants were examined. The total concentration of the 16 PAHs ranged from 12.55 to 10 679.48 ng g-1 dry weight, with a predominance of four-ringed PAHs. Molecular ratio analysis showed pyrolytic sources as the main source of PAHs. Among the metals, Mn, Fe and Zn had the highest concentrations in sediments. General metal levels revealed a multiplicity of point sources and rock weathering as their main source. Regarding the potential ecotoxicological effects, adverse effects may be expected from PAHs because several compounds exceeded the sediment quality guidelines threshold effect level and likely effect level. Conversely, metal levels were below levels specified in safety guidelines. These results are interpreted in an international context, providing information that addresses a gap in the pollution record of Argentinean lakes, and should have strong implications for future planning management.Fil: Oliva, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: la Colla, Noelia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Arias, Andres Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Botté, Sandra Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Perillo, Gerardo Miguel E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Piccolo, Maria Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentin

Water quality analysis based on phytoplankton and metal indices: a case study in the Sauce Grande River Basin (Argentina)

The increasing landscape alterations due to anthropogenic activities is of global concern since it affects aquatic ecosystems, often resulting in compromise of the ecological integrity and the water quality. In this sense, the evaluation, monitoring, and prediction of the aquatic ecosystem quality becomes an important research subject. This study presents the first integrated water quality assessment of the Sauce Grande River Basin, in Argentina, based on the spatial distribution of the phytoplankton community, the physicochemical parameters, and the metal concentrations (Cd, Cu, Cr, Fe, Mn, Ni, Pb, and Zn) found in the particulate fraction. According to the trophic indices and the phytoplankton abundance, composition, and diversity, the water quality showed significant deterioration in the lower basin after the Sauce Grande lake. The trophic state index indicated that water was oligotrophic in over 75% of the sampling sites, increasing downstream, where two sites were characterized as mesotrophic, and one described as hypertrophic. The phytoplankton community was dominated by diatoms in zones with low anthropogenic impact and conductivity, whereas high densities of Euglenophyta, Chlorophyta, and Cyanobacteria were found in the middle-lower basin, associated with higher organic matter and eutrophication. The conductivity, turbidity, and most metal concentrations also increased towards the downstream area, even exceeding recommended levels for the metals Cu, Cr, Mn, and Pb in the middle and lower reaches of the basin (Cu: 3.5 µg L−1; Cr: 2.4 µg L−1; Pb: 1.2 µg L−1; Mn 170 µg L−1). This study generates a database for the water quality of the Sauce Grande River Basin and sets an example of how the water quality varies along a basin that crosses different topographic environments, land covers, and anthropogenic influences.Fil: Zunino, Josefina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: la Colla, Noelia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Brendel, Andrea Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Alfonso, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Botté, Sandra Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Perillo, Gerardo Miguel E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geología; ArgentinaFil: Piccolo, Maria Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentin

ON VISCOSITY AND GEOMETRICAL SOLUTIONS OF HAMILTON JACOBI EQUATIONS

In this paper the author relates a geometric solution for the Cauchy problem to a convex Hamilton-Jacobi equation with its unique viscosity solution. The viscosity solution is shown to correspond to the inf sup of the Morse family generating the geometric solution given previously by the author [Nuovo Cimento B (11) 104 (1989), no. 5, 525--544]. Reviewed by George Kossiori

Estimated acyl chain composition as a function of lipid class based on combined LC-MS and lipid class fractionated GC-MS data [37] for nitrogen replete and deplete <i>Nannochloropsis</i> sp.

<p>Estimated acyl chain composition as a function of lipid class based on combined LC-MS and lipid class fractionated GC-MS data <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0103389#pone.0103389-Olmstead2" target="_blank">[37]</a> for nitrogen replete and deplete <i>Nannochloropsis</i> sp.</p

Heat mapped profile of combined acyl content (3 acyl chains) of TAG in nitrogen replete and nitrogen deplete <i>Chlorella</i> sp. and <i>Nannochloropsis</i> sp.

<p>The assigned values represent the relative proportion of each species normalised to the most prevalent species in each (e.g. 52∶4 for nitrogen replete <i>Chlorella</i> sp.). Values less than 0.01 are not presented.</p

Heat mapped profiles of combined acyl content (2 acyl chains) of glyco- and phosphoglycerolipids in nitrogen replete and nitrogen deplete <i>Chlorella</i> sp. and <i>Nannochloropsis</i> sp.

<p>The assigned values represent the relative proportion of each species normalised to the most prevalent species in each. Values less than 0.01 are not presented.</p