Review about modalities of study using microalgae in the evaluation and monitoring of some lotic systems from the province of Buenos Aires

Los ríos y arroyos pampeanos están expuestos a una fuerte actividad antropogénica (agrícola, ganadera e industrial) mostrando diferentes problemáticas ambientales, desde enriquecimiento con materia orgánica y nutrientes hasta contaminación con desechos industriales. Las características particulares de los ríos y arroyos pampeanos hacen necesario el desarrollo de metodologías e índices apropiados para monitorear la calidad del agua. El propósito de este trabajo es reseñar algunas posibilidades que ofrecen las algas del plancton y del bentos en el diagnóstico de la calidad del agua y su implementación en el biomonitoreo de ecosistemas lóticos bonaerenses y de la costa del Río de la Plata (franja costera sur). Se exponen dos tipos de estrategias, estudios extensivos e intensivos, que difieren en las escalas temporal y espacial. Los resultados de estas investigaciones constituyen una primera aproximación al diagnóstico del estado ecológico de las cuencas estudiadas.The Pampean plain´s running waters are exposed to strong antropogenic activities (agriculture, cattle-raising and industry), showing different environmental problems such as enrichment with organic matter and nutrients and contamination with industrial wastes. The particular features of the pampean streams and rivers require the development of suitable methodology and indices for water quality monitoring. The purpose of this paper is to outline some possibilities offered by the planktonic and benthic algae for the diagnosis of water quality and their implementation in biomonitoring. The investigations were carried out in lotic ecosystems of the province of Buenos Aires and in the coast of the Río de la Plata (southern coastal fringe). Two different types of strategies are exposed, extensive and intensive studies, which differ in the temporal and spatial scales employed. The results of these investigations have contributed with a first approach to the diagnosis of the ecological status of the studied basins.Instituto de Limnología "Dr. Raúl A. Ringuelet"Comisión de Investigaciones Científicas de la provincia de Buenos AiresConsejo Nacional de Investigaciones Científicas y Técnica

Review about modalities of study using microalgae in the evaluation and monitoring of some lotic systems from the province of Buenos Aires

Los ríos y arroyos pampeanos están expuestos a una fuerte actividad antropogénica (agrícola, ganadera e industrial) mostrando diferentes problemáticas ambientales, desde enriquecimiento con materia orgánica y nutrientes hasta contaminación con desechos industriales. Las características particulares de los ríos y arroyos pampeanos hacen necesario el desarrollo de metodologías e índices apropiados para monitorear la calidad del agua. El propósito de este trabajo es reseñar algunas posibilidades que ofrecen las algas del plancton y del bentos en el diagnóstico de la calidad del agua y su implementación en el biomonitoreo de ecosistemas lóticos bonaerenses y de la costa del Río de la Plata (franja costera sur). Se exponen dos tipos de estrategias, estudios extensivos e intensivos, que difieren en las escalas temporal y espacial. Los resultados de estas investigaciones constituyen una primera aproximación al diagnóstico del estado ecológico de las cuencas estudiadas.The Pampean plain´s running waters are exposed to strong antropogenic activities (agriculture, cattle-raising and industry), showing different environmental problems such as enrichment with organic matter and nutrients and contamination with industrial wastes. The particular features of the pampean streams and rivers require the development of suitable methodology and indices for water quality monitoring. The purpose of this paper is to outline some possibilities offered by the planktonic and benthic algae for the diagnosis of water quality and their implementation in biomonitoring. The investigations were carried out in lotic ecosystems of the province of Buenos Aires and in the coast of the Río de la Plata (southern coastal fringe). Two different types of strategies are exposed, extensive and intensive studies, which differ in the temporal and spatial scales employed. The results of these investigations have contributed with a first approach to the diagnosis of the ecological status of the studied basins.Instituto de Limnología "Dr. Raúl A. Ringuelet"Comisión de Investigaciones Científicas de la provincia de Buenos AiresConsejo Nacional de Investigaciones Científicas y Técnica

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Biofilms coating Schoenoplectus californicus as indicators of water quality in the Río de la Plata Estuary (Argentina)

Community composition, structure, biomass and tolerance to pollution of biofilms growing on Schoenoplectus californicus were assessed, together with physico-chemical parameters of the water, to evaluate their usefulness as water quality indicators along the Argentinian shore of the freshwater zone of the Río de la Plata Estuary. Monthly sampling was carried out at three sites, one of which, located in a nature reserve, was considered as the reference site while the others were affected by sewage outlets and port activity. The reference site had higher dissolved oxygen and turbidity values, the polluted sites greater conductivity, oxygen demands, phosphate, ammonium and nitrite values. Diatoms dominated the biofilms at the reference site; ciliates reached higher densities at the polluted sites. Significant differences were found in species numbers, species diversity index, biomass, tolerance to pollution of the taxa, and the Pampean Diatom Index, between the reference and the impacted sites. This study shows that the biofilms growing on Schoenoplectus californicus are good indicators of the changes in the water quality of their environment.Fil: Bauer, Delia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Gomez, Nora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Hualde, Paula R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

Spring phytoplankton of Río de la Plata: a temperate estuary of South America

Phytoplankton community composition, structure and biomass, spatial distribution patterns in relation to abiotic factors and life-form strategies were assessed in spring 2001 in the Río de la Plata estuary. 224 taxa were identified, with a mean total density of 110 cell ml-1. Although cell numbers were of the same order of magnitude in the upper freshwater tidal zone and in the mouth of the estuary, the maximum carbon contents of phytoplankton were observed in the latter, due to the presence of large dinoflagellate cells. Diversity values ranged between 0.3 and 3.2 bits.ind.-1 Chlorophytes and cyanophytes were dominant upstream; diatoms were the most important downstream (in the maximum turbidity front). In the outer, mixohaline zone, diatoms and pyrrophytes were dominant. The phytoplankton of 48% of the Río de la Plata estuary is dominated by riverine specimens. The dominant phytoplankton morphologies in the Río de la Plata were filaments (Planctonema lauterbornii, Ulothrix cf. subconstricta) or chains (Aulacoseira spp., Skeletonema costatum), which provide extensive light absorbing surfaces. Canonical correspondence analysis allowed identification of two species assemblages, one containing freshwater taxa and one with brackish-marine species. In the first group it was recognised that there was a secondary grouping due to the light gradient. Along the fluvial-mixohaline axis it was recognised that the dominant R-strategy species were replaced by S-strategists in the outer sector of the estuary.Fil: Gomez, Nora. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Hualde, Paula R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Licursi, Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Bauer, Delia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin