Artículos y presentaciones en Congresos
URI permanente para esta colección
Examinar
Examinando Artículos y presentaciones en Congresos por Autor "García, Mirta L."
Mostrando 1 - 3 de 3
Resultados por página
Opciones de ordenación
- Artículo
Acceso Abierto Fish assemblages in a small temperate estuary on the Argentinian coast: spatial variation, environmental influence and relevance as nursery area(Universidade de São Paulo, Instituto Oceanográfico, 2015) Solari, Agustín; Jaureguizar, Andrés Javier; Milessi, Andres Conrado; García, Mirta L.The effects of different environmental variables on the fish community structure were evaluated in a small temperate estuary. The biological and environmental data were collected bimonthly between 2007 and 2009 along the main estuarine axis. Multivariate analyses were applied (CLUSTER, SIMPER, CCA) to determine the spatial structure of fish community and to estimate the environmental influence on it. A total of 48 species of teleost fishes were observed, with the families Characidae and Sciaenidae presenting the largest number of species, 90% of the catches being juveniles. The fish community was overwhelmingly dominated by one species (Micropogonias furnieri, 88.9%), and only four species contributed more than 1% of total catch (Odontesthes argentinensis 5.4%, Brevoortia aurea 1.1%, Paralonchurus brasiliensis 1.1%, and Mugil platanus 1.0%). Estuarine and freshwater stragglers dominated in number of species, followed by freshwater migrants and marine migrants. Three areas with different fish assemblages, with distinctive species and functional guilds, were defined along the main axis. The occurrence and spatial spread of these areas were linked to spatial variation in salinity, which was consistently influenced by discharge from the Río de la Plata and local precipitation. The results highlight the importance of shallow environments as nursery areas and permit emphasis on their susceptibility to environmental changes. - Artículo
Acceso Abierto Fish fauna from the Ajó river in Campos del Tuyú National Park, province of Buenos Aires, Argentina(2009) Solari, Agustín; García, Mirta L.; Jaureguizar, Andrés JavierWe provide the first list of the ichthyofauna from the Ajó river, a water course situated at the southward border of the Samborombón bay (36°20'12 ’ S, 56°54'17 W), a RAMSAR site in Argentina. These results were obtained bi-monthly along two years. Forty-five species belonging to 26 families and 11 orders were identified. This fish fauna is composed by freshwater, euryhaline and marine species. Richest groups were Perciformes and Characiformes, with 10 species each. A single species, Micropogonias furnieri (whitemouth croaker), represented more than 70 % of the captured specimens, being juvenile individuals only. Remaining species were also represented by juvenile specimens, confirming the importance of this environment as nursery area, particularly for the whitemouth croaker. - Artículo
Acceso Abierto From fresh water to the slope: fish community ecology in the Río de la Plata and the sea beyond(Universidad Católica de Valparaíso, 2010) García, Mirta L.; Jaureguizar, Andrés Javier; Protogino, Lucila C.The spatial pattern of fish assemblages and its relationship with factors along an environment gradient, from fresh to marine water environment along the Río de la Plata estuary (36ºS, 56ºW) the shelf and part of the slope, was examined using data from 22 sampling stations. Fish were sampled from all station with an Engel type trawl (200 mm stretched mesh in the wings, 120 mm stretched mesh in the cod ends, 4 m vertical opening and 15 m horizontal aperture) towed at 4 knots for 20 to 30 min per set. Cluster analysis and ordination analysis MDS were used to define spatial distribution of fish assemblages based on fish composition (abundance and biomass). BIO-ENV process was used to estimate assemblage association with depth, temperature and salinity of surface and bottom waters. The results of these analyses showed that the fish community along the riverine-marine gradient was structured in four assemblages: riverine, estuarine, shelf and slope. These assemblages were found to differ significantly in their species composition. Each assemblage was characterized by several common and discriminator species and characterized by differing environmental conditions. Bottom salinity and bottom temperature were the environmental variables most strongly associated with differences in assemblage structure across the various areas. The changes in assemblage structure between areas were gradual, with no sharp boundaries.