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Culicidae (Diptera) del arco sur de la Laguna de Mar Chiquita (Córdoba, Argentina) y su importancia sanitaria Culicidae (Diptera) from the southern coast of Mar Chiquita Lake (Cordoba, Argentina) and their sanitary importance  [cached]
Francisco Ludue?a Almeida,Walter R. Almirón,Adriana Zapata,David Gorla
Revista de la Sociedad Entomol?3gica Argentina , 2004,
Abstract: Se amplía la lista de veintidos especies de Culicidae citadas para el arco sur de la Laguna de Mar Chiquita a veintiocho. Aedeomyia squamipennis (Lynch Arribalzaga) , Culex acharistus Root, Culex chidesteri Dyar, Haemagogus spegazzinii Brèthes, Mansonia titillans (Walker) y Psorophora holmbergi Lynch Arribalzaga se citan por primera vez para la región. Se sintetizan los antecedentes relacionados con la importancia sanitaria de los culícidos de la zona. The list of twenty-two species of Culicidae from the southern coast of Mar Chiquita Lake is extended to twenty-eight. Aedeomyia squamipennis (Lynch Arribalzaga) , Culex acharistus Root, Culex chidesteri Dyar, Haemagogus spegazzinii Brèthes , Mansonia titillans (Walker) and Psorophora holmbergi Lynch Arribalzaga are listed for the first time for the region. The available information on sanitary importance of the culicids of the area is summarized.
Análisis de la morfología ósea de peces de la laguna costera Mar Chiquita, Argentina
Deli Antoni,Mariana Y; González Castro,Mariano; Díaz de Astarloa,Juan M;
Revista de biología marina y oceanografía , 2008, DOI: 10.4067/S0718-19572008000200013
Abstract: the morphological analysis of the bones is a valuable tool for taxonomy, which has allowed the definition of the higher groups of vertebrates and descriptions and identifications of fish species. therefore, the compared osteology provides valuable diagnostic elements in biodiversity studies, ecology and dynamics of trophic habits of piscivore fish. the goal of the present study is to make a descriptive and comparative osteological analysis that allow the identification of the main fish species occurring in mar chiquita coastal lagoon: the brazilian menhaden (brevoortia aurea), the mullet (mugil platanus), the silver side (odontesthes argentinensis), the white croaker (micropogonias furnieri), the black drum (pogonias cromis), the flounder (paralichthys orbignyanus), the blue fish (pomatomus saltatrix), the stripped weakfish (cynoscion guatucupa) and the southern kingfish (menticirrhus americanus). six specimens of each species were analyzed and methods to disarticulate skeletons in fresh and frozen specimens were used. on the basis of the diagnostic characteristics of the bones and their degree of digestibility resistance, eleven bones were selected: parasphenoid, lachrymal, premaxilla, dentary, anguloarticular, palatine, hyomandibular, ceratohyal, urohyal, preopercle and posttemporal. each bone has been described, and according to the most important differences found among fish species, identification keys were elaborated. we conclude that bone morphology constitutes a valuable diagnostic tool for the identification of fish species occurring in mar chiquita coastal lagoon and coastal adjacent areas.
ALIMENTACION DE ODONTESTHES BONARIENSIS (CUVIER Y VALENCIENNES 1835) (ATHERINIFORMES, ATHERINIDAE) EN LA LAGUNA SALADA DE MAR CHIQUITA (CORDOBA, ARGENTINA) FEEDING OF ODONTESTHES BONARIENSIS (CUVIER Y VALENCIENNES 1835 1835) (ATHERINIFORMES, ATHERINIDAE) IN THE SALINE LAKE OF MAR CHIQUITA (CORDOBA, ARGENTINA  [cached]
Luis Sagretti,María de los Angeles Bistoni
Gayana (Concepción) , 2001,
Abstract: Se analizó el contenido estomacal de 258 individuos de pejerrey Odontesthes bonariensis, con el objeto de estudiar los hábitos alimentarios de esta especie en un ambiente de características particulares debido a su extensión y elevada salinidad. El material fue recolectado en la costa sur de la laguna Mar Chiquita, en muestreos con frecuencia estacional durante 1994-1995. Se determinó el espectro trófico, estableciéndose para cada ítem la frecuencia de ocurrencia, abundancia y volumen. Se calculó el Indice de Importancia Relativa (IRI). El pejerrey preda principalmente sobre organismos animales. Se encontraron variaciones en el componente principal de la dieta de acuerdo a la longitud alcanzada por el pejerrey, observándose una marcada ictiofagia en aquellos que superan los 200 mm de longitud estándar. La única presa íctica consumida fue Jenynsia multidentata, habiéndose registrado sólo dos casos de canibalismo. Las capturas de esta especie en la costa disminuyeron en oto o e invierno. Este factor podría ser la causa del cambio alimentario estacional. El alimento de mayor importancia registrado para verano y primavera fueron los peces, mientras que en oto o predominaron con un elevado valor de IRI los caracoles y en invierno los insectos. Dentro de estos últimos, los órdenes más importantes fueron Diptera y Hemiptera. Si nos basamos en la alimentación de O. bonariensis al estado adulto, se concluye que el pejerrey se comporta en la laguna Mar Chiquita como una especie ictiófaga The aim of this work was to study the feeding habits of silverside Odontesthes bonariensis in a habitat characterized by its extension and high salinity. Stomach contents of 258 individuals were analyzed. Seasonal frequency sampling was conducted in the southern coast of Mar Chiquita Lake during 1994-1995. The trophic spectrum was determined, establishing the frequency of occurrence, abundance and volume for each item. The Index of Relative Importance (IRI) was estimated. O. bonariensis behaves as a zoophagous species. The main component of the diet varied according to fish size, showing a marked ichthyophagy in those specimens with more than 200 mm in standard length. O. bonariensis fed almost exclusively on Jenynsia multidentata. Cannibalism occurred only twice. The capture of the latter species decreased in autumn and summer. This could explain the seasonal variation registered in the diet of the silverside (O. bonariensis). The main food item in spring and summer were fish, whereas snails Littoridina parchappe and insects were the most important preys in autumn and winter res
Culicidae (Diptera) del arco sur de la Laguna de Mar Chiquita (Córdoba, Argentina) y su importancia sanitaria
Ludue?a Almeida,Francisco; Almirón,Walter R.; Zapata,Adriana; Gorla,David;
Revista de la Sociedad Entomol?3gica Argentina , 2004,
Abstract: the list of twenty-two species of culicidae from the southern coast of mar chiquita lake is extended to twenty-eight. aedeomyia squamipennis (lynch arribalzaga) , culex acharistus root, culex chidesteri dyar, haemagogus spegazzinii brèthes , mansonia titillans (walker) and psorophora holmbergi lynch arribalzaga are listed for the first time for the region. the available information on sanitary importance of the culicids of the area is summarized.
ALIMENTACION DE ODONTESTHES BONARIENSIS (CUVIER Y VALENCIENNES 1835) (ATHERINIFORMES, ATHERINIDAE) EN LA LAGUNA SALADA DE MAR CHIQUITA (CORDOBA, ARGENTINA)
Sagretti,Luis; Bistoni,María de los Angeles;
Gayana (Concepción) , 2001, DOI: 10.4067/S0717-65382001000100006
Abstract: the aim of this work was to study the feeding habits of silverside odontesthes bonariensis in a habitat characterized by its extension and high salinity. stomach contents of 258 individuals were analyzed. seasonal frequency sampling was conducted in the southern coast of mar chiquita lake during 1994-1995. the trophic spectrum was determined, establishing the frequency of occurrence, abundance and volume for each item. the index of relative importance (iri) was estimated. o. bonariensis behaves as a zoophagous species. the main component of the diet varied according to fish size, showing a marked ichthyophagy in those specimens with more than 200 mm in standard length. o. bonariensis fed almost exclusively on jenynsia multidentata. cannibalism occurred only twice. the capture of the latter species decreased in autumn and summer. this could explain the seasonal variation registered in the diet of the silverside (o. bonariensis). the main food item in spring and summer were fish, whereas snails littoridina parchappe and insects were the most important preys in autumn and winter respectively. among the insects the most important orders were diptera and hemiptera. o. bonariensis in the adult stage can be considered an ichthyophagous species based on its feeding habits in the mar chiquita lake
Dinámica e implicancia del aluvión de la laguna 513, Cordillera Blanca, Ancash, Perú Dinamics and implications of the laguna 513 Aluvion, Cordillera Blanca, Ancash Perú  [cached]
Patricio Valderrama,Oscar Vilca
Revista de la Asociación Geológica Argentina , 2012,
Abstract: La Cordillera Blanca, al norte de Perú, es la zona con más actividad geodinámica externa en Perú. En ella ocurrieron grandes flujos de detritos de origen glaciar, varios de ellos fueron grandes desastres y cobraron miles de vidas. El 11 de abril del 2010, la laguna 513, ubicada en el centro de la Cordillera Blanca, sufrió un desembalse parcial por la caída de un gran bloque de hielo y rocas del nevado Hualcán (5500 m.s.n.m.). Este evento pese a ser de dimensiones considerables, no generó grandes pérdidas ni afectó alguna ciudad importante. Mediante simulaciones numéricas de flujo se estudió su dinámica, se determinó sus volúmenes y su turbulencia así como también explicamos e papel de la morfología de la zona en la desaceleración del flujo, su encausamiento en un valle fluvial y su posterior comportamiento como crecida de río. Las simulaciones realizadas mediante FLO2D se validan mediante comparaciones con imágenes de satélite post evento y datos de campo. The Cordillera Blanca in northern Peru is the most external geodynamics active areas in Perú. There have been occurred the biggest glacier source debris flow in the Peruvian history, most of them became on major disasters and claimed thousands of lives. On April 11th, 2010, the Laguna 513, located in the center of the Cordillera Blanca, suffered a partial GLOF due a massive rock and ice fall from Nevado Hualcán (5500 masl). This event, despite being of considerable size, did not generate large losses or affect any major city. Using numerical simulations we study the dynamics of the consequent GLOF and debris flow. We determined the volume and turbulence as well as also explained the role of the geomorphology of the area in the flow deceleration process and the river flood subsequent behavior. The FLO 2D simulations are validated with post event satellite image and field data.
Chiquita en Colombia
Simone Bunse,Forrest Colburn
Academia : Revista Latinoamericana de Administración , 2009,
Abstract: Este caso trata sobre Chiquita Brands International y su decisión de pagar a los paramilitares en Colombia por la seguridad de sus empleados. Estos pagos, comunes en Colombia y otros países de América Latina, son ilegales en Colombia y los Estados Unidos. Unos a os después de ocurridos los pagos Chiquita fue investigada por el Departamento de Justicia de los Estados Unidos y enfrentó multas por 25 millones de dólares. El caso se presta para analizar los incentivos a corto plazo frente a los de largo plazo y para explorar las percepciones sobre el comportamiento ético frente a uno inmoral en entornos operativos extremadamente difíciles.
Herpetofauna en relictos de Bosque Chaque o de la región de Mar Chiquita, Córdoba
Briguera, Verónica,Tamburini, Daniela,Kufner, Maura Beatriz,Gavier, Gregorio
Cuadernos de Herpetología , 2006,
Abstract: Remanentes significativos de Bosque Chaque o y de su biodiversidad se encuentran en la Reserva Ba ados del Río Dulce y Laguna de Mar Chiquita y su zona de influencia. En dos localidades dentro y fuera de la misma se estudió la herpetofauna en el hábitat chaque o. La estructura del hábitat se analizó a partir de la cobertura vegetal por estratos y la altura del dosel. La composición y diversidad específicas de la herpetofauna se estudió mediante captura muerta y búsqueda activa. La estructura de la vegetación no difirió estacionalmente; sí entre localidades, con mejor condición fuera del área protegida. La escasa estacionalidad actual de las lluvias se manifestaría en 60% de especies comunes y similar diversidad específica de la herpetofauna. En campos privados colindantes con la reserva, tuvieron mejor representación los ofidios, las especies endémicas (Stenocercus doellojuradoi y Philodryas baroni) y otras seis en estado poblacional comprometido. Estos remanentes de bosque constituyen reservorios de la biodiversidad chaque a ante la expansión de la frontera agropecuaria en Córdoba. Significant remnants of Chacoan forest and its biodiversity, exist in the Ba ados of Río Dulce and Laguna of Mar Chiquita reserve, and its influence area. In two localities, inside of and outside of the protected area, were studied the herpetological fauna, and the importance of conserving related forest fragments. Habitat structure was analyzed through vegetation covering by strata, and the height of canopy. The composition and specific diversity of the herpetological fauna were studied by means of dead capture and active search. The structure of vegetation didn't differ seasonally but among localities, and presented better condition outside the reserve. Amphibians and snakes showed more richness in the humid and dry periods, respectively. However, the influence of current less different between-season precipitations, was apparent in 60% of common species and a similar specific diversity of herpetological fauna. In private fields adjacent with the reserve, good condition of forest favored better representation of ophidians, endemic species (Stenocercus doellojuradoi and Philodryas baroni), and other six species in vulnerable population status. These forest fragments contribute as reservoirs of the Chacoan biodiversity, against the expansion of the agricultural frontier in Córdoba
Pollen deposition in tauber traps and surface soil samples in the Mar Chiquita coastal lagoon area, pampa grasslands (Argentina)  [cached]
Fabiana Latorre,Claudio F. Pérez,Silvina Stutz,Susana Pastorino
Boletín de la Sociedad Argentina de Botánica , 2010,
Abstract: Estimations of airborne pollen loadings deposited in Tauber traps were studied in a coastal lagoon from south-eastern Pampa grasslands, Argentina, in order to assess their relationship with surface samples and to interpret the representativeness of local, regional and extraregional vegetation. Three different environments were considered: a coastal dune barrier with a psammophytic community, a salt marsh with a halophytic community in Mar Chiquita lagoon, and a freshwater community at Hinojales freshwater lake. Based on a record of surface samples taken from a previous paper, a parametric model was built to classify Tauber samples gathered from the natural vegetation communities of the study area. Results revealed that just like their surface counterparts, Tauber trap records qualitatively reflect the predominant vegetation types, although ecological groups feature different quantitative representations depending on the record type. Pollen loadings showed that airborne pollen transport was predominantly of local range, in accordance with previous results from the same study area. Airborne - surface samples relationships enrich our knowledge of the present environment that could be useful to improve paleoecological interpretations of the area. Se estimó el depósito polínico atmosférico de trampas Tauber en una laguna costera del sudeste de la estepa pampeana argentina, con el objetivo de analizar su relación con muestras de polen superficial e interpretar la representatividad de la vegetación local, regional y extraregional. Se consideraron tres ambientes diferentes: una barrera costera de dunas con vegetación psamofítica, la marisma de la laguna costera Mar Chiquita, con vegetación halofítica, y la laguna continental Hinojales, con vegetación hidrofítica. En base a las muestras de superficie y análisis de un trabajo previo, se construyó un modelo paramétrico para clasificar las muestras Tauber tomadas en la vegetación natural del área de estudio. Los resultados revelan que como su contraparte en suelo superficial, los registros polínicos Tauber reflejan cualitativamente los tipos de vegetación predominante, aunque los tipos ecológicos difieren cuantitativamente su representación, según el tipo de registro observado. Los datos de polen muestran que el transporte atmosférico de polen es predominantemente local, de acuerdo con resultados previos en la misma área. Las relaciones entre muestras aéreas y de superficie enriquecen nuestro conocimiento del ambiente actual el cual puede ser útil para mejorar las interpretaciones paleoecológicas en el área.
Coastline evolution at Balneario Parque Mar Chiquita, Argentina
Merlotto, A;Bértola, GR;
Ciencias marinas , 2009,
Abstract: this study determined coastline evolution and retreat rates at balneario parque mar chiquita (argentina) between 1949 and 2007. the dune toe was considered the coastline indicator, and it was determined based on historical maps, aerial photographs, a satellite image, and field measurements. the analysis showed that the intensity of the erosion process has declined though it continues to be meaningful. the annual rate has decreased from 17.71 to 1.41 m yr-1, corresponding to a total retreat of 299.01 m in the last 58 years. the temporal variations of the phenomenon mainly result from changes in beach nourishment by the littoral drift, which has been affected by sand mining and coastal defenses built to the south of the study area. different spatial behaviours were also registered in the town, associated with geomorphological characteristics and dune conservation state. sudestada storms have played a significant role in the coastline retreat. the results contribute to the understanding of the magnitude and dynamics of the erosion process, and should be of use in the preparation of coastal management programs and risk evaluations.
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