Amphipoda (Crustacea: Peracarida) da Plataforma Continental e Bancos OceÃnicos da RegiÃo Nordeste do Brasil: Programa REVIZEE III e IV

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

In the world, taxonomy and ecology of Amphipoda from tropical regions are few studied if compared to other temperate regions and high latitudes. Thus, the present work had as objective to study the Amphipodaâs community from the Continental Shelf and Oceanic Banks of the Northeast Region, Brazil collected during the REVIZEE-NE Program. A total of 3.103 individuals collected by dredging at 30 stations during May and June, 1998 and November and December, 2000 on board the N/O âAntaresâ were analyzed. Temperature, depth, salinity and sediment data were measured at each station. Organisms were fixed with alcohol 70% and identified under Wild stereomicroscope and Zeiss microscope using the specialized references. Community was characterized by the following biological descriptors: total abundance, specific diversity, equitability, occurrence frequency and Margalefâs richness. The Mann-Whitney âUâ test was used with significance level of 95% (α = 0.05) to verify the differences among these descriptors. It was also used the Multivariate analyses: Cluster, Principal Components (ACP) and Multidimensional Scaling (MDS). As expected for Northeast Regionâs oceanographic characteristics; temperature and salinity were almost constant, with averages over 27ÂC and 36 UPS, respectively. Depth varied from 22 to 74 m. A total of 73 species were identified, with 61 new occurrences for the oceanic banks from Cadeia Norte and Fernando de Noronha, and 14 new occurrences for the Occidental South Atlantic. Leucothoe tridens, Gammaropsis (Gammaropsis) atlantica, Leucothoe urospinosa and Elasmopus sp. were the most frequent species. Fernando de Noronha presented highest diversity, abundance, average richness compared to the Continental Shelf and Cadeia Norte. All stations presented equitability values higher than 0.5, being the sandiest shape more equitable than the coarsely one (α = 0.028). Firstly, the ACP showed the biological interactions and secondarily, the type of sediment as main factors regulating the Amphipoda community in the Northeast Region from Brazil. Clustering analysis and the MDS showed the importance of sediment type, especially granulometry, on the characterization of subareas studied

ASSUNTO(S)

bancos oceÃnicos ânordeste, brasil revizee program amphipoda (crustacea: peracarida) amphipoda (crustacea: peracarida) plataforma continental â nordeste, brasil oceanografia continental shelf â northeast, brazil oceanic banks â northeast, brazil oceanografia programa revizee

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