Seasonal and short-term variations in the copepod community of a shallow Amazon estuary (Taperaçu, Northern Brazil)
Magalhães, A.; Nobre, D.S.B.; Bessa, R.S.C.; Pereira, L.C.C.; da Costa, R.M. (2011). Seasonal and short-term variations in the copepod community of a shallow Amazon estuary (Taperaçu, Northern Brazil). J. Coast. Res. SI 64: 1520-1524
In: Journal of Coastal Research. Coastal Education and Research Foundation: Fort Lauderdale. ISSN 0749-0208; e-ISSN 1551-5036, more
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Keyword |
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Author keywords |
Zooplankton, Secondary production, Coastal ecosystem |
Authors | | Top |
- Magalhães, A.
- Nobre, D.S.B.
- Bessa, R.S.C.
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- Pereira, L.C.C.
- da Costa, R.M.
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Abstract |
As they are involved in the turnover of nutrients and the flow of carbon and energy to higher consumers in aquatic food webs, copepods play a crucial role in most coastal and estuarine environments. Despite their importance, no data are available on the productivity of these organisms or of any other zooplankton group in the estuarine and neritic waters of the Brazilian Amazon coast. Given this, the present study investigated the seasonal and short-term variation in the abundance, biomass and productivity of copepods in the Taperaçu estuary relative to temporal and seasonal fluctuations in hydrological variables. Zooplankton were collected at a fixed station during two 24 h periods in the rainy (July) and dry season (October) of 2004. Specimens were collected using a plankton net with a 300 μm mesh towed through the station at 3 hour intervals. Twenty two copepod taxa were identified, of which Acartia lilljeborgii was the numerically dominant species. The local copepod populations were characterized by a lack of significant short-term (circadian or tidal) variation, which may be related to the unique geomorphological and hydrodinamical features of the estuary. Nevertheless, accentuated seasonal fluctuations were recorded in the biological attributes of these populations. The high copepod productivity observed in the studied area can be related to the high salinity, temperatures and concentrations of organic detritus from the local mangroves. |
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