Fishes from the Parque Nacional do Pantanal Matogrossense, upper Paraguai River basin, Brazil.

The Pantanal Biosphere Reserve contains one of the highest concentration of animal species in the Neotropics, including about 300 fish species living in diverse environments associated with wetlands in the upper Paraguai River basin. This biome spans portions of Bolivia, Brazil and Paraguay and includes the Parque Nacional do Pantanal Matogrossense (PNPM), a region of the Pantanal which has been assigned as high conservation priority in Brazil. This study reports the results of an ichthyological survey within the PNPM, where samples were taken at 12 sites during the dry season in 2001, 2010 and 2011. We record 182 species representing three classes, 10 orders and 41 fish families. We report the first occurrence of the genus Anchoviella (order Clupeiformes), in the La Plata basin. This survey will provide information for future studies concerning conservation and management plans for the PNPM as well as for the Pantanal, which is one of the largest permanent wetland areas in the world and among the most unique and important South American biomes

Itaipu reservoir limnology: eutrophication degree and the horizontal distribution of its limnological variables

Os reservatórios são ambientes artificiais e intermediários entre rios e lagos, apresentando características morfométricas e hidrológicas distintas, com alta taxa de renovação da água e organizações vertical e horizontal características. A evolução desses ecossistemas depende de variáveis que atuam em diferentes escalas espaciais e temporais. A evolução da qualidade da água do Reservatório de Itaipu foi avaliada por meio da análise das variáveis físicas, químicas e biológicas e da aplicação de índices de Estado Trófico. Observou-se que as variáveis limnológicas químicas e físicas apresentaram um padrão de variação espacial (horizontal) e temporal fortemente dependente do regime hidrológico. Os efeitos da turbidez e os sólidos suspensos totais apresentaram o mesmo padrão de distribuição por zona do reservatório. A zona fluvial foi a que apresentou as maiores concentrações de nutrientes, sólidos suspensos e turbidez. Os resultados dos Índices de Estado Trófico indicaram um estado de mesotrofia para as zonas fluvial e de transição e oligotrofia para a zona lacustre.Reservoirs are manmade habitats, intermediate between rivers and lakes, presenting distinct hydrological and morphometric characteristics, with differential mean water residence time. They also present proper vertical and horizontal organisations, and their evolution depends on several variables acting on different special and temporal scales. The water quality evolution of the Itaipu Reservoir was evaluated through the analysis of the physical, chemical and biological variables, and by the application of Trophic State Indices. We concluded that the limnological variables present a horizontal pattern of variation highly dependent upon the hydrological regime. The turbidity and total suspended solids presented the same distribution pattern in the reservoir zones. The fluvial zone had the highest concentrations of nutrients, suspended solids and turbidity. The results of the Trophic State Indices indicate a mesotrophic level for the fluvial and transition zones, and an oligotrophic one for the lacustrine zone.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Itaipu reservoir limnology: eutrophication degree and the horizontal distribution of its limnological variables

Reservoirs are manmade habitats, intermediate between rivers and lakes, presenting distinct hydrological and morphometric characteristics, with differential mean water residence time. They also present proper vertical and horizontal organisations, and their evolution depends on several variables acting on different special and temporal scales. The water quality evolution of the Itaipu Reservoir was evaluated through the analysis of the physical, chemical and biological variables, and by the application of Trophic State Indices. We concluded that the limnological variables present a horizontal pattern of variation highly dependent upon the hydrological regime. The turbidity and total suspended solids presented the same distribution pattern in the reservoir zones. The fluvial zone had the highest concentrations of nutrients, suspended solids and turbidity. The results of the Trophic State Indices indicate a mesotrophic level for the fluvial and transition zones, and an oligotrophic one for the lacustrine zone