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Carvalho Rodrigo A. Teresa Fabrício B. Tejerina-Garro Francisco L. 《Hydrobiologia》2021,848(2):515-529
Hydrobiologia - We investigated how the riverine network influences taxonomic and functional beta diversity patterns of fish assemblages in the mainstem/headwater (lateral) and upstream/downstream... 相似文献
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Afonso Pereira Fialho Leandro Gonçalves Oliveira Francisco Leonardo Tejerina-Garro Bernard de Mérona 《Hydrobiologia》2008,598(1):315-324
This study analyzes the interaction of fish assemblages with 14 physicochemical and hydrogeomorphological variables at 31
sampling stations along the watershed of the Meia Ponte River, Upper Paraná Basin, Central Brazil, during low and high water
seasons in 2001. This river and its tributaries drain both urban and agricultural areas. Fish were caught with sieves along
a 100 m stretch demarcated in every sampling site, where environmental variables were also measured. A total of 3508 individuals
belonging to 31 species were collected. Fish abundance and environmental data matrices were submitted to a multivariate analysis
of co-inertia. Two axes were retained for interpretation (total variance explained = 63.65%) indicating that pH, water temperature,
conductivity, chemical dissolved oxygen, and turbidity, all have an influence on fish assemblage structure. The co-structure
found (fish assemblages and physicochemical variables) is correlated in both of the axes considered (r = 0.73 and r = 0.68, respectively), and is statistically significant (Monte Carlo test, P < 0.001). This co-structure is regulated by seasonality, but is influenced by fish habitat preferences, spawning and available
food, the extent and effects of anthropogenic activities (domestic sewage, agriculture, ranching, urban areas) and the position
of sampling stations along the watershed.
Handling editor: S. M. Thomaz 相似文献
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Bernard?de?MéronaEmail author Régis?Vigouroux Francisco?Leonardo?Tejerina-Garro 《Hydrobiologia》2005,551(1):33-47
Dams are expected to decrease fish diversity because they deeply alter downstream environment. However, such decline has not
been consistently observed although profound modifications in the structure and/or composition of fish communities were generally
recorded, and were linked to modifications of the downstream environment. In this work we analyze data from observations made
before and almost 10 years after the completion of a hydroelectric dam in the neotropics. We monitored fish diversity below
that dam and compared the taxonomic and functional structures of the samples between the pre- and post-dam periods. A significant
decrease in species richness was evidenced. Taxonomic and trophic structures were significantly different between the two
periods. Conversely, the functional structure of samples based on reproductive traits did not change significantly after the
damming. Concerning feeding habits, a large increase in relative abundance of detritivores and a parallel decrease of fish
species feeding on terrestrial food sources were observed in samples taken 6–9 years after closure of the dam as compared
with samples taken before the dam. 相似文献
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