Sustainable water resources management for irrigated agriculture in Latin America

[No abstract available]EU/FP

Humic Substances from sediments of Lobos Pond (Argentina). Isolation, Characterization and Limnological Implications

Humic substances (HS) were isolated from the sediments of Lobos Pond (Argentina) using mild conditions to preserve their native structure. The HS (humic and fulvic acids) were characterized by means of elemental analysis and FTIR spectroscopy. Also a by-product obtained during fulvic acids (FA) fractionation (an amorphous white solid residue) was analyzed. Results revealed possible interactions between FA and inorganic-organic substances that may have implications referring to bioavailability. Other limnological implications, such as autochtonous origin of HS linked with the hydrology, and change of pH during stormy weather that affects HS interactions, are discussed.Laboratorio de Investigación de Sistemas Ecológicos y Ambientale

Humic Substances from sediments of Lobos Pond (Argentina). Isolation, Characterization and Limnological Implications

Humic substances (HS) were isolated from the sediments of Lobos Pond (Argentina) using mild conditions to preserve their native structure. The HS (humic and fulvic acids) were characterized by means of elemental analysis and FTIR spectroscopy. Also a by-product obtained during fulvic acids (FA) fractionation (an amorphous white solid residue) was analyzed. Results revealed possible interactions between FA and inorganic-organic substances that may have implications referring to bioavailability. Other limnological implications, such as autochtonous origin of HS linked with the hydrology, and change of pH during stormy weather that affects HS interactions, are discussed.Laboratorio de Investigación de Sistemas Ecológicos y Ambientale

Humic Substances from sediments of Lobos Pond (Argentina). Isolation, Characterization and Limnological Implications

Humic substances (HS) were isolated from the sediments of Lobos Pond (Argentina) using mild conditions to preserve their native structure. The HS (humic and fulvic acids) were characterized by means of elemental analysis and FTIR spectroscopy. Also a by-product obtained during fulvic acids (FA) fractionation (an amorphous white solid residue) was analyzed. Results revealed possible interactions between FA and inorganic-organic substances that may have implications referring to bioavailability. Other limnological implications, such as autochtonous origin of HS linked with the hydrology, and change of pH during stormy weather that affects HS interactions, are discussed.Laboratorio de Investigación de Sistemas Ecológicos y Ambientale

A gravitational-wave standard siren measurement of the Hubble constant

The detection of GW170817 (ref. 1) heralds the age of gravitational-wave multi-messenger astronomy, with the observations of gravitational-wave and electromagnetic emission from the same transient source. On 17 August 2017 the network of Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)2 and Virgo3 detectors observed GW170817, a strong signal from the merger of a binary neutron-star system. Less than two seconds after the merger, a γ-ray burst event, GRB 170817A, was detected consistent with the LIGO–Virgo sky localization region4–6). The sky region was subsequently observed by optical astronomy facilities7, resulting in the identification of an optical transient signal within about 10 arcseconds of the galaxy NGC 4993 (refs 8–13). GW170817 can be used as a standard siren14–18, combining the distance inferred purely from the gravitational-wave signal with the recession velocity arising from the electromagnetic data to determine the Hubble constant. This quantity, representing the local expansion rate of the Universe, sets the overall scale of the Universe and is of fundamental importance to cosmology. Our measurements do not require any form of cosmic ‘distance ladder’19; the gravitational-wave analysis directly estimates the luminosity distance out to cosmological scales. Here we report H0 = kilometres per second per megaparsec, which is consistent with existing measurements20,21, while being completely independent of them

Multi-messenger Observations of a Binary Neutron Star Merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ȯ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p

Arsenic and fluoride levels in water for dairy cattle (Province of Córdoba, Argentina)

Southeastern Cordoba (Argentina) is one of the regions in the country more affected by high arsenic groundwaters. Poor water quality may influence the development of agricultural activities in spite of the favorable edaphic and climatic characteristics. Water quality for dairy cattle was evaluated in 32 dairy farms (Long. 62º 33´ W and 62º 57´ W; and Lat. 32º 12´S and 32º 50´ S) that use groundwater as the main source. Wells take water from different depth (3 - 15 m, 40% and 80 - 150 m, 44%). Mayor ion concentrations are within the recommended values in water for dairy cattle. Arsenic and fluoride contents are higher in shallow groundwater where a 52.6% and a 84.2% of the samples, respectively, show higher concentrations than those recommended for dairy cattle, while only 5.6% of samples from deeper perforations were above the suggested limits for both elements.Fil: Pérez Carrera, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaFil: Fernández Cirelli, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaEl sudeste de la provincia de Córdoba (Argentina) es una de las zonas más afectadas de nuestro país por los niveles de arsénico en agua subterránea. De acuerdo con sus características edafoclimáticas, esta región posee excelentes aptitudes agropecuarias, pero sufre limitaciones debido a la calidad del recurso hídrico disponible. En este trabajo, se evaluó la calidad del agua de bebida animal en 32 establecimientos lecheros de la zona (62º 33´ - 62º 57´ long. oeste y 32º 12´ - 32º 50´ lat. sur), cuya fuente principal es subterránea y proviene de perforaciones de la capa freática (3 - 15 m de profundidad, 40%) o de perforaciones semi surgentes (80 - 150 m de profundidad, 44%). Las concentraciones determinadas para iones mayoritarios se encuentran dentro de los límites recomendados. Los niveles de arsénico y flúor son mayores en la capa freática, donde un 52,6% y un 84,2% de las muestras, respectivamente, superan los límites máximos recomendados para agua de bebida de bovinos. En aguas provenientes de perforaciones semisurgentes, sólo un 5,6% de las muestras resultó no apta en relación con su contenido de arsénico y flúor.\

Arsenic in the southeast plains of Cordoba province, Argentine. Biotransference to bovine milk

Trace element transference from environmental matrices to the agricultural food chain is an actual phenomenon that is being analyzed in different regions of the world. Nevertheless, knowledge about trace element content in food, particularly in milk, is scarce. In Argentine, an element of great concern is arsenic due to its natural occurrence in groundwater in large areas of the country. The aim of the present work was determine arsenic content in livestock drinking water and milk from dairy farms located in the southeast of the Cordoba province. Arsenic concentrations in all collected phreatic samples suggested the possibility of transference to bovine milk. Arsenic levels in soils and forage were among the normal levels for regions of natural occurrence of this element. No toxicity for humans could be expected from the arsenic concentrations determined in milk. A biotransference factor (BTF) of arsenic to bovine milk from cattle arsenic intake was calculated for our production systems in the conditions of our country.Fil: Pérez Carrera, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaFil: Fernández Cirelli, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaLa transferencia de elementos traza desde matrices ambientales a la cadena agroalimentaria es un fenómeno que está siendo estudiado en distintas regiones del mundo. Sin embargo, la información acerca de los niveles en alimentos, particularmente la leche, es escasa. En nuestro país, un elemento de particular relevancia es el arsénico (As), por su ocurrencia natural en aguas subterráneas en una amplia zona de nuestro territorio. En este trabajo se determinaron las concentraciones de As en agua de bebida animal, suelo, forraje y leche en establecimientos lecheros del sudeste de la provincia de Córdoba. Los niveles de As determinados en agua de bebida, en particular en aquellos establecimientos que extraían el agua de la capa freática, sugerían la posibilidad de transferencia de As a la leche bovina. Los niveles en suelo y forraje estuvieron dentro de los rangos de valores normales para regiones de abundancia natural de As. Las concentraciones de As determinadas en muestras de leche no revestían toxicidad para consumo humano. Los resultados obtenidos permitieron estimar un factor de biotransferencia (FBT) de As a leche bovina a partir de la ingesta de este elemento por parte de los animales, en las condiciones productivas y edafoclimáticas de nuestro país

Importancia de las propiedades de los suelos en la determinación del riesgo de contaminación de acuíferos Importance of soil properties in the risk of groundwater contamination

La vulnerabilidad de acuíferos es usualmente estimada por metodologías que no tienen en cuenta los principales parámetros físico-químicos de los suelos. Se determinaron las características de suelos en una zona periurbana de Buenos Aires con actividades mixtas. Se propuso un índice de atenuación (IA) para estimar el riesgo de contaminación química de acuíferos, que tuvo en cuenta el Cox, pH, CIC y contenido de arcillas, profundidad de la capa freática y la posición del suelo en el paisaje. Los suelos de Escobar son Molisoles y Entisoles con gran variabilidad en su composición química. Los contenidos de P, Mn, Zn en las aguas subterráneas fueron utilizados para validar el IA, encontrando relación entre este índice y los mencionados elementos. El contenido de arcillas es una propiedad muy importante en la sorción de P, debido a que su incremento está directamente relacionado con el aumento en la retención del ion. Existió una relación significativa entre los parámetros edáficos Cox, CIC y P extractable y las propiedades químicas del agua con el IA.Aquifer vulnerability is frequently estimated through methodologies that do not consider the main physical and chemical soil parameters. Soil characteristics were determined at a semiurban region with mixed activities at the surroundings of Buenos Aires city. A soil attenuation index (AI) was proposed to estimate groundwater chemical pollution risk, that takes into account organic carbon content, pH, cation exchange capacity, clay content, phreatic depth and landscape position. Escobar soils were Mollisols and Entisols with a high variation in soil properties. Phosphorus, Mn and Zn concentrations in groundwater samples taken from selected places were used to validate the proposed index. Clay content was a very important property for adsorption, as clay increased, the soil P retention capacity increased simultaneously. A relationship was found between CEC, Cox and extractable P and chemical water properties with AI

Arsenic and fluoride removal from water used in livestock production

Edaphoclimatic conditions in Argentina enable the favorable development of agricultural activities. Most of them are concentrated in the chacopampean plain where livestock drinking water is mainly groundwater. These water sources usually contain significative concentrations of trace elements such as arsenic (As) and fluoride (F), originated in volcanic events during soil formation. The occurrence of As and F in drinking water could have deleterious effects on the human and livestock health. In the present paper, the commonly used techniques for As and F removal cited in the literature are listed and the efficiency of several methodologies previously studied in CETA with the target to remove trace elements from animal drinking water, are reviewed. In particular, an adsorbent material of geogenic origin, laterite, was used as both, adsorbent and forming part of a constructed wetland. Among the main results, it was found that laterite is a good option for the removal of pollutants such as As and F, even in high conductivity water samples, and the efficiency is increased, in the case of As, with the addition of cover plants that are capable of extracting the As from the water once the support is saturated. Thus, the construction of wetlands in rural areas is seen as a promising alternative for groundwater decontamination. Moreover, this technology has wide acceptance among the inhabitants due to its low cost, easy operation, and its integration with the environment.Fil: Cotorro, C. Agua y Saneamientos Argentinos S.A. (AySA S.A.). ArgentinaFil: Iriel, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaFil: Iriel, A. CONICET - Universidad de Buenos Aires. Instituto de Investigaciones en Producción Animal (INPA). Buenos Aires. ArgentinaFil: Fernández Cirelli, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaFil: Fernández Cirelli, A. CONICET - Universidad de Buenos Aires. Instituto de Investigaciones en Producción Animal (INPA). Buenos Aires. ArgentinaFil: Pérez Carrera, A. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Centro de Estudios Transdisciplinarios del Agua (CETA). Buenos Aires, ArgentinaFil: Pérez Carrera, A. CONICET - Universidad de Buenos Aires. Instituto de Investigaciones en Producción Animal (INPA). Buenos Aires. ArgentinaNuestro país cuenta con excelentes condiciones edafoclimáticas para el desarrollo de actividades agropecuarias que se concentran en la llanura chaco-pampeana donde el agua utilizada para bebida animal es fundamentalmente de procedencia subterránea. Dichas fuentes de agua poseen disueltas cantidades importantes de sales que en determinadas regiones contienen niveles significativos de elementos traza como arsénico (As) y flúor (F) -entre otros- procedentes de eventos de vulcanismo que tuvieron lugar durante la formación del suelo. La presencia de estos elementos podría tener efectos deletéreos en la salud de los animales y de los pobladores que la consumen. En este trabajo se enumeran las técnicas comúnmente empleadas para la remoción de As y F que se encuentran en bibliografía y se revisa la eficiencia de metodologías previamente estudiadas en el CETA con el objeto de remover microcontaminantes presentes en agua. En particular, se estudió el uso de materiales adsorbentes de origen geogénico, laterita, que se utilizó sola como adsorbente y también formando parte de un humedal construido con especies vegetales de cobertura. Entre los resultados principales se encontró que la laterita resulta eficiente para la remoción de contaminantes como As y F, aún en muestras de alta conductividad, y que esa eficiencia se ve aumentada, en el caso del As, con el agregado de las plantas de cobertura que son capaces de extraer el As del agua una vez que el soporte se encuentre saturado. Así, la construcción de humedales en zonas de población dispersa aparece como una alternativa promisoria para la decontaminación de agua subterránea. Por otro lado, esta tecnología posee amplia aceptación entre los pobladores debido a su bajo costo, fácil operación y su integración con el ambiente