Variações espaciais na assembléia de peixes no Rio Paraíba do Sul (Barra Mansa, Barra do Piraí), Rio de Janeiro, Brasil

Abstract

ABSTRACT. Spatial Variation in Fish Assemblage in the Paraíba do Sul River (Barra Mansa, Barra do Piraí), Rio de Janeiro, Brazil. The Paraíba do Sul is a major running water system in southeastern Brazi I (22°24 ' -22°26 ' S; 43°43' _44° 16' W), draining one of the most important industrial regions in the country. Because of its location, it has suftered a large amount 01' alteration due to discharges of urban and industrial eftluents with direct innuence in the ichthyotàuna. The aim ofthis study is to up-to-date information on fish assemblage structure and its variation in the vic inity 01' a major industrial effluent outfall at Volta Redonda industrial complex. A standardized fishing sampling program, using seines, casting nets, gill nets and net trays, was carried out from October 1997 to September 1999, at six sites in three zones of the river (upstream, nearby and downstream lhe industrial complex), aiming to compare variation in fish assemblage due to anthropogenic alteration. Fifty-two species in 13 families were identified in the total of 7286 fish specimens. Characidae was the most divel'se family contributing with 28,85% to total number of species, followed by Cichlidae (17,31 %). Overall 15,38% ofthe species were introduced from other watershed systems, four exotic cichl ids (genera Oreochromis Günther, 1862 and Tilapia A. Smith, 1840) and three aloctone (CieMa oeellaris Bloch & Schneider, 1801 , Hyphessobrieol1 eallis/us (Boulenger, 1900) e Me/yl1l1is maeula/us (Kner, 1860)). Lebistes retielllatlls (Peters, 1859) was the most abundant tish species contributing to 39,7% of the total number of fish, followed by Geophagus brasiliellsis (Quoy & Gaim ard, 1824) amounting to 27,4%. Fish abundance was higher in the industrial zone, but only a few very dominant species were captured, while the upstream zone showed the most even community. Species replacement tolerance along the altel'ations gradient in the three zone seems to be a strategy to use the limited resources in the area. KEY WORDS. Rivers, tish taxocenose, pollution, ichthyofauna, fish ecology o rio Paraíba do Sul é um ecossistema de grande importância, pois suas águas são utilizadas, tanto para consumo doméstico e industrial, como para a produção de energia, suprindo cerca de 90% da demanda do município do Rio de Janeiro e arredores (SILVEIRA el a!. 1979;BARROSO 1989). Apesar desta importância, poucas são as informações atualizadas sobre a biota, tais como as assembléias de peixes, organismos estes importantes como indi cadores da qualidade ambien tal do rio. O trecho mais utilizado, e portanto mais alterado do rio, situa-se entre Barra Mansa e Barra do Piraí, onde o rio atravessa o complexo industrial

Distribution of guppies Poecilia reticulata (Peters, 1860) and Phalloceros caudimaculatus (Hensel, 1868) along a polluted stretch of the Paraíba do Sul River, Brazil

“…mechanism to maintain and reestablish the structure of populations, and this seems to be a characteristic of the whole group. Similar distribution patterns for these two species were also found by Araújo et al (2001), with P. reticulata being the most abundant fish species at Z2, while P. caudimaculatus, ranked as the third most abundant species at Z3. The use of deteriorated areas by opportunistic fish species has been reported by several workers (Hughes and Gammon, 1987;Soto-Galera et al, 1998;Harris and Silveira, 1999;Pinto et al, 2006b;Pinto and Araújo, 2007).…”

“…In this scope, P. reticulata and P. caudimaculatus have been reported as indicators of poor water condition due to their ability to thrive in harsh environmental conditions (Araújo, 1983). Both species have been recorded along the Paraíba do Sul River mainly in more polluted stretches (Araújo et al, 2001;Teixeira et al, 2005;Pinto et al, 2006b;Pinto and Araújo, 2007). On the other hand, fish condition indicates health and can be influenced by environmental conditions (Vila-Gispert and Moreno-Amichi, 2001).…”

Diversidade das assembléias de peixes nas quatro unidades geográficas do rio Paraíba do Sul

“…Relações de espécies têm sido reportadas para o rio Paraíba do Sul como parte de compilações, porém sem precisar os locais e períodos de amostragens (BIZERRIL, 1999); outras são restritas a determinados trechos (ARAÚJO, 1996;ARAÚJO et al, 2001), não fornecendo um quadro abrangente do sistema. Por outro lado, as 92 espécies de água doce para este sistema, incluídas na compilação de FOWLER (1948de FOWLER ( , 1950de FOWLER ( , 1951de FOWLER ( , 1954, fornecem um quadro mais compreensivo da riqueza do rio.…”

“…A estimativa de uma riqueza de 130 espécies para grandes rios da bacia do Leste, como o Paraíba do Sul, foi feita por BIZERRIL (1999), incluindo o levantamento da ictiofauna de pequenos riachos, dos quais, vários componentes não chegam a ocorrer no canal principal. ARAÚJO (1996) registrou 57 espécies de água doce entre os trechos médio-inferior e inferior; ARAÚJO et al (2001) registraram 52 espécies para o canal principal do rio entre os municípios de Barra Mansa e Barra do Piraí, um trecho considerado de maior nível de poluição por PFEIFFER et al (1986). Comparações da riqueza de espécies entre trabalhos com diferentes níveis de esforço podem ser pouco confiáveis do ponto de vista quantitativo, embora tenham grande importância como informação qualitativa.…”

Space–Time Distribution of the Ichthyofauna from Saco da Fazenda Estuary, Itajaí, Santa Catarina, Brazil

“…In Brazil, most studies dealing with estuarine fish assemblages were made in Rio de Janeiro (Andreata et al, 1990(Andreata et al, , 2002Araú jo et al, 1998Araú jo et al, , 2001Brum et al, 1994;Costa, 1984;Pessanha et al, 2000), Paraná Bouchereau, 1999a, 1999b;Chaves and Corrêa, 1998;Neto et al, 2004;Santos et al, 2002;Spach, Santos, and Godefroid, 2003;Spach et al, 2004;Vendel et al, 2002), Rio Grande do Sul (Chao et al, 1982;Vieira, 1997, 2001;Godefroid et al, 2004;Pereira, 1994;Silva, 1982) and in some areas of the north states (Araú jo, Teixeira, and Oliveira, 2000;Camargo and Isaac, 2001;Castro, 2001;Lopes, Oliveira-Silva, and Ferreira-Melo, 1998;Vasconcelos-Filho and Oliveira, 1999). Although Santa Catarina's coast has a fair number of important estuaries, their fish assemblages have been seldom DOI: 10.2112/08-1050.1 received 30 July 2008accepted in revision 1 August 2008. studied (Hostim-Silva et al, 2002).…”