Conteúdo Calórico de Músculos de Prochilodus Lineatus (Characiformes, Prochilodontidae) no Reservatório de Manso, Brasil

Com o objetivo de conhecer as variações intraespecíficas no conteúdo calórico, presentes em músculos de Prochilodus lineatus, foram analisados 118 espécimes durante o período de outubro 2002 a setembro 2003 no reservatório de Manso, Mato Grosso, Brasil. De cada exemplar foram obtidas as medidas morfométricas, identificando o sexo e estádio de maturação gonadal e extraindo amostras da musculatura da base da nadadeira dorsal. Cinco amostras de diferentes regiões da musculatura foram amostradas de 18 fêmeas em repouso para se verificar a existência de diferenças calóricas num mesmo indivíduo, associadas à região muscular. Todas as amostras foram secas em estufa a 60ºC até alcançar peso constante, maceradas, homogeneizadas e submetidas à queima em bomba calorimétrica (PARR). Não foram identificadas variações significativas entre diferentes regiões da musculatura, bem como entre sexos. Entre os estádios reprodutivos, apenas para fêmeas verificaram-se diferenças significativas, sendo o estádio repouso significativamente diferente dos demais. Para machos, durante o estádio de maturação, as amostras musculares apresentaram maior concentração calórica que nos demais estádios. A análise de correlação entre o comprimento padrão e o conteúdo calórico dos músculos das fêmeas demonstrou que para indivíduos no estádio de repouso existe correlação. Entre os machos, a correlação embora baixa, foi significativa para indivíduos imaturos, em repouso e em maturação. O presente estudo confirma a importância de se considerar as variações calóricas por classe de comprimento e ressalta a importância de se compreender as alterações energéticas decorrentes da maturação gonadal.Fil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Pinheiro dos Santos, Erik Allan. Universidade Federeral de Sergipe; BrasilFil: Marques Domingues, Wladimir. Universidade Estadual de Maringá; BrasilFil: Benedito, Evanilde. Universidade Estadual de Maringá; Brasi

The influence of hydro‐climatic and anthropogenic effects on the long‐term variation of commercial fisheries in a large floodplain river

This study deals with the effects of climate fluctuations and anthropogenic impacts on fisheries of Paraná River over the last 100 years. It is the first attempt to appraise the influence of hydro-climatic and anthropogenic variables on the population changes of the most important inland fisheries of Argentina. Datasets covering more than eight decades (1935–2016) of a number of frequent and abundant commercial species inhabiting the main channel as well as the large floodplain of Paraná River were used. Our results suggest that fish catches and structure changed over time. Long and short-term changes and reductions were closely related to fluctuations of 18 hydro-climatic variables. Positive effects on the ichthyofauna were recorded during humid periods (1930–1940 and 1970–2000), when the frequency of large spring–summer floods increased. An increase in anthropic impacts (accounted for with nine variables) were recorded during the last two decades. We highlight the usefulness of the approach to support the management of the resources, ensuring sustainability of commercial fish assemblages and the long-term conservation of biodiversity in big rivers.Fil: Rabuffetti, Ana Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Abrial, Elie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Eurich, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

Detecting drug use in adolescents using a 3D simulation program

This work presents a new 3D simulation program, called Mii School, and its application to the detection of problem behaviours appearing in school settings. We begin by describing some of the main features of the Mii School program. Then, we present the results of a study in which adolescents responded to Mii School simulations involving the consumption of alcoholic drinks, cigarettes, cannabis, cocaine, and MDMA (ecstasy). We established a “risk profile” based on the observed response patterns. We also present results concerning user satisfaction with the program and the extent to which users felt that the simulated scenes were realistic. Lastly, we discuss the usefulness of Mii School as a tool for assessing drug use in school settings

Fishers’ knowledge on a large floodplain river in South America. Contributions for sustainable management of inland fisheries

This study presents a comparison between fishers’ knowledge and fiscal records about the structure of inland fisheries in the Paraná River (Argentina). First of all, we characterized the fishing population according to the main demographic and economic indicators, identifying two different fishing areas: the northern and southern sections in the lower La Plata basin. Secondly, we carried out a comparative analysis of fiscal fishery records (from two commercial sets: 1930–1984 and 2011–2019) and local fishers’ knowledge on inland commercial fisheries (frequency of occurrence and abundance). Finally, we contrasted current fishing regulations (allowed meshes and boats, fishing prohibitions, exports) to fishers’ effective practices. The study area included 52 sites located along the floodplain of the middle and lower sections of the Paraná River, in the province of Santa Fe. Socioeconomic analyses identified two different groups of fishers throughout the river corridor. Results showed that fishers have detailed knowledge on nomenclature, ecology, reproductive strategy, habitat distribution, and usefulness of commercial fish species. By contrasting fishers’ knowledge with fiscal records, we found similar and complementary information about the changes in abundance and frequency of occurrence in fisheries. These results highlight the need of including local knowledge as an outstanding source of information for well-planned management of fishing programs and sustainable policies.Fil: Rabuffetti, Ana Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Pablo. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Ferreira, Patricio. Universidad Nacional del Litoral; ArgentinaFil: Abrial, Elie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

Hydrodynamic and morphologic effects on the benthic invertebrate ecology along a meander bend of a large river (Paraguay River, Argentina-Paraguay)

A detailed hydro-ecological study to identify the effects of bed flow and morphodynamic processes on the distribution (and composition) of benthic invertebrates in a large river is presented herein. A crossing-pool sequence in a meander bend of the Paraguay River (Paraguay-Argentina) was examined. According to the results, there is a link between the benthic fauna, hydraulic and bed sediment size along the bend. The meander pool, with a deep scour hole and the largest bed shear stresses, would be a hostile area for benthic invertebrates, since lower densities were found there. A transversal analysis revealed two different invertebrate assemblages at each of the sampled cross sections: one across the mobile bottom with higher densities but lower diversity, richness and evenness than the other one found close to the banks. On the other hand, a comparison between both Paraguay and Paraná rivers revealed that the first one would seem to have optimal hydraulic conditions for the invertebrate's development, because the hydraulic energy of the Paraná River was too intense for the favorable settlement of benthic organisms at some specific habitats. The overall conclusion of this paper, that morpho-hydraulic features and biotopes are related, is an important step forward in river ecohydrology. With further development of this concept, river management techniques can improve and river rehabilitation projects can be designed with greater confidence.Fil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Ezcurra de Drago, Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Drago, Edmundo Carlos E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Paira, Aldo Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

Impact of climatic fluctuations on commercial fisheries in the Paraná River along the last century

We analysed the effects of decadal and annual hydrologic fluctuations on freshwater fisheries catches in the Middle Paraná River for a period of six decades from the 1930s to the 1980s. We first analysed changes in the flow regime of the Paraná River for the period between 1930s and 1980s, with focus on the variations of the flood pulse. To build and compare flow typology among years, we used cluster analysis. Principal component analysis (PCA) was used to assess overall similarity of flows among years. The fisheries catch analysed (1935-1983) were obtained along this river corridor. The obtained data consisted of landing reports on monthly/annual catches (total and by species) in ports along the Paraná River. Differences in total catches among decades were tested using a one-way permutational analysis (PERMANOVA). The canonical analysis of the principal coordinates (CAP) was used to assess temporal patterns of similarity in fish catches per decades. To analysed the effects of flow regime variables on the variation of fish commercial catches we used distance-based redundancy analyses (dbRDAs). The climatic fluctuations in this period strongly affected the hydrology of the Middle Paraná River and the characteristics of its flow regime. The magnitude of floods as well as maximum, minimum and mean water levels increased progressively from 1930s until the 1980s concomitantly with increasing frequency and intensity of ENSO events that resulted in differentiation of distinct hydrological periods. The flood pulses were significantly more frequent and of greater magnitudes during the 1970s and 1980s. These large floods resulted in increased commercial fish catches in the 1980s, possibly due to enhanced recruitment. Specifically, large floods increased the commercial fish catches two years later. This effect was stronger for species that use floodplain habitats as areas of reproduction and larval nurseries, such as Prochilodus lineatus. We conclude that the natural flow regime of the Paraná River and perhaps other large subtropical rivers must be preserved in order to sustain their productive fisheries.Trabajo publicado en Acta Bioquímica Clínica Latinoamericana; no. 52, supl. 2, parte II, diciembre de 2018.Universidad Nacional de La Plat

Discrimination of hydrologic variations for spatial distribution of fish assemblage in a large subtropical temperate river

This study examines the effects of the flow and flood pulses on spatialdispersion of fish assemblages in the floodplain of the Paraná River in Argentina. Wetested the hypothesis that high water levels and greater lateral connectivity promotefish dispersal and spatial homogenization of assemblage structure. We sampled foursites during different phases of the annual hydrologic cycle from 2010 to 2016. Watersurface in the area was estimated during each phase. We computed multivariatestatistics and estimates of ß-diversity to analyze assemblage variations in relation tohydrological phases. Three hydrological phases were defined: low flow pulses (waterlevels between 2.3 and 3.2, approximately 10% of the floodplain covered by water),high flow pulses(between 3.2 and 4.5, from 11 to 84%), and floods (> 4.5 m, morethan 84%). Although difference between high flow pulses and flood was notsignificant, ß-diversity values for these stages were higher than for low flow pulses.This suggests that floods and high flow pulses increase the spatial variability of fishassemblages, whereas homogenization processes occur later during low flowperiods. This work provides further knowledge about the flood homogenization effectin a large unregulated floodplain where lateral connectivity still plays a significant roleon ecological structuring processes.Fil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Abrial, Elie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Rabuffetti, Ana Pia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Simoes Da Silva, Nadson Ressyé. Universidade Federal Do Sul Da Bahia. Centro de Formação Em Ciências Ambientais.; BrasilFil: Amsler, Mario Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Blettler, Martin Cesar Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Eurich, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Paira, Aldo Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin

Linking hydro-morphology with invertebrate ecology in diverse morphological units of a large river-floodplain system

Interdisciplinary research in the fields of ecohydrology and ecogeomorphology is becoming increasingly important as a way to understand how biological and physical processes interact with each other in river systems. The objectives of the current study were 1) to determine changes in invertebrate community due to hydrological stages, 2) to link local physical features [flow configuration, sediment composition and morphological feature) with the ecological structure between and within dissimilar morphological units (meander and confluence), and 3) to determine the existence and the origin of bed hydro-geomorphic patches, determining their ecological structure. Results were discussed in the frame of prevailing ecological models and concepts. The study site extends over a floodplain area of the large Paraná River (Argentina), including minor and major secondary channels as well as the main channel. Overall results suggested that hydrodynamics was the driving force determining distribution patterns of benthic assemblages in the floodplain. However, while the invertebrates living in minor secondary channels seem to benefit from flooding, this hydrological phase had the opposite effect on organisms from the main and major secondary channels. We also found a clear linkage between physical features and invertebrate ecology, which caused a dissimilar fauna structure between and within the meander and the confluence. Furthermore, several sandy-patches were recorded in the confluence. These patches were colonized by the particular benthic assemblage recorded in the main channel, supported the view of rivers as patchy discontinua, under uncertain ecological equilibrium.Instituto de Limnología "Dr. Raúl A. Ringuelet

Basis to study the alterations of the hydrological regime and its ecological importance in Argentina

En este trabajo se plantean las bases metodológicas para evaluar los cambios antrópicos que afectan las condiciones ecohidrológicas a una escala regional en la Argentina. La diversidad climática, morfológica y geológica del territorio se manifiesta en diferentes ecorregiones y en una diversidad elevada de ambientes lóticos y lénticos ligados a los sistemas hídricos. Los caudales diarios, los niveles freáticos, las superficies anegadas o las alturas hidrométricas tienen distinta influencia según la ecorregión considerada en cada sistema hídrico. La información hidrológica histórica con continuidad y los registros con una extensión suficiente para analizar las alteraciones del régimen hidrológico son relativamente escasos y se restringen a 163 estaciones de medición. Se plantea aplicar un modelo conceptual para analizar las alteraciones hidrológicas, seguido del estudio de las variaciones temporales en las condiciones hidrológicas y morfológicas previas a la actividad antrópica (preimpacto), para luego considerar la nueva situación hidrológica-ecológica (post-impacto), a partir de las que se deberán adoptar las medidas apropiadas para mitigar los daños ecológicos cuando se produzcan. Aunque existen diversas metodologías para realizar dicho análisis, considerando la disponibilidad de datos actuales en la Argentina, se propone emplear el marco metodológico fundamentado en el concepto ELOHA (Ecological Limit of Hydrological Alteration) para analizar las alteraciones hidrológicas. Si bien el método holístico brinda mejores resultados y menor incertidumbre, considerando la heterogeneidad, la escasez y la falta de continuidad de registros hidrológicos a nivel general, la técnica propuesta podría resultar una buena aproximación a escala regional. Se concluye que será necesario adaptar las bases metodológicas y las técnicas de análisis a tal condición para crear una base de datos para planificar estratégicamente los recursos hídricos en la Argentina.In this work, we propose the bases for assessing the ecohydrological changes resulting from direct and indirect human activities at a regional scale in Argentina. The climatic, morphological and geological diversity of the territory is manifested in different ecoregions and in a high diversity of lotic and lentic environments which are closely linked to the water systems. Daily flows, groundwater levels, flooded surfaces or hydrometric heights have different influences depending on the ecoregion considered in each water system. The historical hydrological information with continuity and records with a sufficient extension for the analysis of the alterations of the hydrological regime are relatively scarce and restricted to 163 measuring stations. The application of a conceptual model for the analysis of hydrological alterations is proposed, followed by the study of temporal variations in the hydrological and morphological conditions prior to the anthropic activity (pre-impact), to then consider the new hydrological-ecological situation (post-impact), on the basis of which appropriate measures should be adopted to mitigate the ecological damage when they occur. Although there are various methodologies to conduct this analysis, considering the availability of current data in Argentina, we propose the use of the methodological framework based on the ELOHA (Ecological Limit of Hydrological Alteration) concept for the analysis of hydrological alterations. Although the holistic method provides the best results and the least uncertainty, considering the heterogeneity, scarcity and lack of continuity of hydrological records at a general level, the proposed technique could be a good approximation at a regional scale. It is concluded that it will be necessary to adapt the methodological bases and analysis techniques to this condition in order to create a database for the strategic planning of water resources in Argentina.Fil: Rodrigues Capitulo, Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Hidrología General; ArgentinaFil: Espínola, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Yoya, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Gaspari, Fernanda Julia. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Mazzucchelli, Maria Gabriela. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales; ArgentinaFil: Kruse, Eduardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Cátedra de Hidrología General; Argentin