|
|
|
Registros recuperados: 11 | |
|
| |
|
|
Zuanon,Jansen; Bockmann,Flávio A.; Sazima,Ivan. |
We studied a specialised assemblage of sand-dwelling fish species from a streamlet in central Amazonia. The five sanddwelling species comprised 15.2 % of the total number in the streamlet (33 species). Two of the sand-dwellers are daytime foragers, Characidium cf. pteroides (Crenuchidae) and Stauroglanis gouldingi (Trichomycteridae), whereas three ones are night-time foragers, Gymnorhamphichthys rondoni (Rhamphichthyidae), "Imparfinis" pristos and Mastiglanis asopos (Heptapteridae). With the exception of C. cf. pteroides, the remainder species bury in the sand during their resting period. All five species bear a cryptic, sand-colour pattern, and some are translucent, traits which we regard as advantageous both for evasion from predators and for approaching... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Forest streams; Fish diversity; Phylogeny; Feeding behaviour; Drift-trap net. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000100012 |
| |
|
|
Chevillot, Xavier; Pierre, Maud; Rigaud, Arthur; Drouineau, Hilaire; Chaalali, Aurelie; Sautour, Benoit; Lobry, Jeremy. |
For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We... |
Tipo: Text |
Palavras-chave: Ecosystem state; Fish diversity; Estuary; Generalised linear mixed models; GLMM; Time series; Shift; Inter-shift periods. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00334/44567/44282.pdf |
| |
|
| |
|
|
Virgilio, Lucena Rocha; Ramalho, Werther Pereira; Silva, João Carlos Barbosa da Silva; Suçuarana, Monik da Silveira; Brito, Cleyton Holanda de; Vieira, Lisandro Juno Soares. |
The degradation of riparian vegetation in low-order streams can cause irreversible environmental damage, biodiversity loss and alter the structure of communities. In this context, the present study evaluated how the level of degradation of riparian vegetation influences the fish assemblage in three low-order streams in the Brazilian Amazon. In each stream, three different stretches were delimited, distributed in the environments of forest, edge and pasture, and the samplings were conducted in three hydrological regimes using dip nets. Influences of the stretches and streams on richness and abundance were tested with GLMM, on the composition with PERMANOVA and on indicator species with IndVal. Species richness was higher in forest environments and lower in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Low-order streams; Environmental alteration; Diversity loss; Fish diversity; Indicator species; Pasture.. |
Ano: 2018 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/42562 |
| |
|
|
Silva,André R. M.; Santos,Gilmar B.; Ratton,Thiago. |
Many rivers in Brazil as the São Francisco (SFR) have been impounded for reservoirs construction purposes. However, there is a lack of knowledge on their fish fauna in many areas, including headwaters. The present study aimed to describe the fish community structure from Juramento reservoir, located on Juramento River, a branch of SFR basin. Six bimonthly samplings were made in four different sites. Gill and cast nets, beach seines and sieves were used to collect fish. Ecological indexes as well as the relationship between fish abundance and some limnological variables were determined. 3288 fish belonging to 33 species (16.5% of the total described for SFR basin) were captured, being 75.7% Characiformes, 18.1% Siluriformes, 3% Cyprinodontiformes and 3%... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish diversity. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752006000300031 |
| |
|
|
Súarez,Yzel Rondon; Valério,Sabrina Bigatão; Tondado,Karina Keyla; Florentino,Alexandro Cezar; Felipe,Thiago Rota Alves; Ximenes,Lidiani Queli Lubas; Lourenço,Luzia da Silva. |
The influence of spatial, temporal and environmental factors on fish species diversity in headwater streams in Paraguay and Paraná basins, Brazil was examined. A total of 4,605 individuals were sampled, distributed in 60 species. The sampled streams in Paraná basin presented a larger total species richness (42) than Paraguay streams (40). However the estimated richness was larger in Paraguay basin (53) than Paraná streams (50). The streams of Paraná basin had a greater mean species richness and evenness, while more individuals per sample were found in the Paraguay basin. Difference between the sub-basins were found in the Paraguay basin, while for the basin of Paraná, richness and evenness vary significantly between the sub-basins, but the number of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Community ecology; Fish diversity; Streams; Paraguay Basin; Paraná Basin. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000700014 |
| |
|
|
Santos,Alex Braz Iacone; Terra,Bianca de Freitas; Araújo,Francisco Gerson. |
Changes in fish assemblage structure along a longitudinal gradient of the Paraíba do Sul River and Funil reservoir were studied to detect distribution patterns and the seasonal influence of the inflowing river. Fish were caught by gill nets in three zones (riverine, transition and lentic) during two seasons (dry and wet). A total of 3,721 individuals were captured, comprising five orders, 14 families, 27 genera and 33 species. Five species were non-native and amounted to 17.7% of the total number of individuals. The 10 most abundant species were used to assess spatial-temporal patterns. Plagioscion squamosissimus (Heckel, 1840), Oligosarcus hepsetus (Curvier, 1829) and Metynnis maculatus (Kner, 1858) were widely distributed in both seasons. Astyanax... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Dam; Fish diversity; Paraíba do Sul River; Seasonality. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702010000500010 |
| |
|
|
Morales-Cazan,Alfy; Albert,James S.. |
The systematics and taxonomy of poeciliid fishes (guppies and allies) remain poorly understood despite the relative importance of these species as model systems in the biological sciences. This study focuses on testing the monophyly of the nominal poeciliine tribe Heterandriini and the genus Heterandria, through examination of the morphological characters on which the current classification is based. These characters include aspects of body shape (morphometrics), scale and fin-ray counts (meristics), pigmentation, the cephalic laterosensory system, and osteological features of the neurocranium, oral jaws and suspensorium, branchial basket, pectoral girdle, and the gonopodium and its supports. A Maximum Parsimony analysis was conducted of 150 characters... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish diversity; Heterandria; Ichthyology; Osteology; Pseudoxiphophorus; Systematics. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100003 |
| |
|
|
Anjos,Maeda Batista dos; Zuanon,Jansen. |
Small streams are important components of the landscape in terra firme forests in central Amazonia and harbor a large number of fish species. Nevertheless, the lack of a common sampling protocol in studies of this ichthyofauna hinders comparisons among available results. This study evaluates how the length of stream reach sampled affects estimates of local fish species density in 1st, 2nd, and 3rd order streams, and proposes a mean minimum sampling length that best approximates the absolute number of species in a given stream segment. We sampled three streams in the Biological Dynamics of Forest Fragments Project's study sites, between May and August 2004. At each stream, one 1st order, one 2nd order, and one 3rd order segment was sampled. We sampled five... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish diversity; Fish abundance; Stream size; Species composition; Species accumulation curves. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000100006 |
| |
|
| |
Registros recuperados: 11 | |
|
|
|