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Este trabalho apresenta uma experiencia pedagogica e, tambem, uma pesquisa realizada com estudantes em uma saida de campo utilizando-se aspectos da bacia hidrografica como tema gerador e continuada, em termos reflexivos, na sala de aula. A dimensao epistemologica adotada na atividade pratica foi pautada na concepcao freireana, por meio do dialogo e da problematizacao critico-reflexiva dos problemas socioambientais vivenciados pelos estudantes. Por meio da analise quali e quantitativa da dinâmica de grupo focal, questionario e registros em campo, identificou-se, em um primeiro momento, uma visao predominantemente individualista e antropocentrica da natureza. Constatou-se que ao longo das atividades didatico-pedagogicas, no campo e em sala de aula, a discussao se ampliou de maneira critico-reflexiva e os relatos foram ao encontro da construcao do conhecimento. O corpo discente tambem destacou a importância dos espacos nao formais nesse processo. Practical environmental education activity in the non-formal space: aspects of the hydrographic basinas a generator theme This work presents a pedagogical experience and, also, a research done with students on a field trip using aspects of the hydrographic basin as a generator theme and continued, in reflective terms, in the classroom. The epistemological dimension adopted in the practical activity was ruled on the Freirean conception, through dialogue and critical-reflective problematization of the socio-environmental problems experienced by the students. Through the qualitative and quantitative analysis of the focus group dynamics, field questionnaire and records, identified himself at first, a predominantly individualistic and anthropocentric view of nature. It was found that throughout the didactic-pedagogical activities, in the field and in the classroom, the discussion expanded in a critical-reflective way and the reports met the construction of knowledge. The student body also highlighted the importance of non-formal spaces in this process. Keywords: Environmental education. Teaching. Interdisciplinarity. Critical-reflective.

Fragmentation and interconnection of water bodies cause severe changes in the natural flow regime of continental water systems. However, assessments of these impacts on the freshwater fish distribution are still scarce. We investigated whether an artificial flow regime generated by discharges from an aqueduct would promote a longitudinal environmental gradient in an off-river reservoir. We tested the hypothesis that the incoming water from aqueduct discharges promotes environmental gradient between lotic and lentic conditions. We expect that environmental changes and the artificial flow regime promote the structuring of fish assemblage and that the lotic-lentic transition areas present the highest fish species richness. A longitudinal gradient in environmental characteristics with differing fish assemblage structure was found. Temporal changes in the fish assemblages occurred only in areas near the discharge of the aqueduct. The highest fish richness and diversity were recorded in the transition zone during the wet season, associated with the greater environmental heterogeneity of this ecotone, whereas the lowest was found in the lotic zone, probably associated with the altered flow regime. The greatest abundance was recorded in the upper lentic zone in the wet season, whereas the lowest was found in the lower lentic zone in both seasons. Our results corroborate the hypothesis that the artificial flow regime, modulated by the seasonality of discharges and the influence of environmental variables, promotes longitudinal gradients in reservoirs when rivers are not present. The findings are relevant in a scenario where ever more interconnections of aquatic bodies have been diffused around the world.

The relationship between taxonomic and functional diversity indices has been used to better describe and understand the structure of biological communities. Functional diversity is expected to have an asymptotic relationship with species richness because at some point, the addition of new species will increase some of the already established functional groups (functional redundancy). However, the asymptotic relationship may not be reached in intermediately disturbed systems once many intolerant species that would have played a redundant role or even represented some functional groups have been lost. This study aimed to address such a relationship (taxonomic and functional indices) and to evaluate the functional redundancy in intermediately disturbed streams in the Atlantic Rainforest domain. We expected a positive linear relationship between taxonomic and functional diversity; however, we did not expect to find an asymptotic relationship between richness and functional diversity because of the loss of many intolerant species caused by anthropogenic uses. The taxonomic diversity indices were Species Richness (SR) and Simpson’s Diversity (SD), while the functional diversity indices were the Functional Richness (FRic) and Functional Dispersion (FDisp). The two taxonomic and two functional diversity indices showed a significant positive relationship that never reached an asymptote, suggesting low functional redundancy in the fish communities. Our results indicate that care is needed in the management of the studied streams because assemblies with low functional redundancy are more susceptible to loss of functions in the case of species loss.

The first records of 2 species of Parodontidae (Apareiodon piracicabae and A. itapicuruensis) are reported in theParaíba do Sul river basin. In total, 101 individuals of A. piracicabae and 3 individuals of A. itapicuruensis werecollected in the Paraíba do Sul middle reaches. A description and diagnosis of both species based on morpho-meristiccharacters were provided. These fishes have been used as forage for larger fish species as well as bait for sport fishing,which may have facilitated their introduction in the Paraíba do Sul River from fish culture farms in the region.

Pseudocorynopoma heterandria Eigenmann, 1914 is a characid related to streams and lakes of clear waters in areas of low and medium altitude (Menezes et al., 2007). The original distribution of this species is in the coastal rivers of S~ao Paulo and Paran a, Brazil (Reis et al., 2003), and has never been recorded below 23°S latitude. In this study we report the first record of P. heterandria in the Para iba do Sul River (20°260–23°380S; 41°000–46°300W), which is located outside of its original area of occurrence. We compared morphometric characteristics of P. heterandria from the Para iba do Sul River basin with the original description of Eigenmann (1914), since local environmental constraints may influence morphological divergence in this species. Additionally, we report for the first time the length–weight relationship (LWR) for this species.