Davy Barbosa Bérgamo , Josefa Nilmara Lopes Lacerda , Rilda Verônica Cardoso de Araripe , Antônio Vicente Ferreira Júnior , David Holanda de Oliveira
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引用次数: 0
Abstract
Benthic foraminifera are valuable proxies for oceanographic and environmental research due to their high degree of species-specific habitat use. The present study describes the distribution of benthic foraminifera across the continental carbonate shelf of northeastern Brazil, and relates their distribution patterns to environmental parameters associated with the texture of the sediment and the depth of the water. Sediment samples were collected at depths between 0.5 and 57 m. In the laboratory, the samples were analyzed following the standard protocol established for Quaternary foraminifera research. Sediments dominated by carbonate sand, which were approximately symmetric in the first depth interval (0.5–20 m), and asymmetric in the second (20–40 m) and third (40–57 m) intervals. The foraminiferal assemblages composed of 96 species, although they were dominated by the five species – Archaias angulatus, Textularia agglutinans, Amphistegina lessonii, Quinqueloculina lamarckiana, and Peneroplis carinatus. Most tests were intact and the species composition varied across the continental shelf, with Pseudotriloculina laevigata and Globobulimina? sp. Only occurring from 0.5 to 20 m depth in shelf, while Pyrgo elongata, Quinqueloculina sp. A, Quinqueloculina sp. C, Fissurina sp. A, Fissurina sp. B, Elphidium morenoi, Glabratella brasilensis, and Siphogenerina sp. Were restricted from 20 to 40 m, and Sigmoilina sp., Fursenkoina sp., and Textularia sp. A was only recorded in depth >40 m. The diversity of the foraminiferal assemblages is favored by the attenuation of hydrodynamic conditions at deeper intervals (20–57 m). Therefore, it can be concluded that the benthic foraminiferal species respond to the depth and variation in sediment characteristics through changes in their population and assemblage structures.
期刊介绍:
Continental Shelf Research publishes articles dealing with the biological, chemical, geological and physical oceanography of the shallow marine environment, from coastal and estuarine waters out to the shelf break. The continental shelf is a critical environment within the land-ocean continuum, and many processes, functions and problems in the continental shelf are driven by terrestrial inputs transported through the rivers and estuaries to the coastal and continental shelf areas. Manuscripts that deal with these topics must make a clear link to the continental shelf. Examples of research areas include:
Physical sedimentology and geomorphology
Geochemistry of the coastal ocean (inorganic and organic)
Marine environment and anthropogenic effects
Interaction of physical dynamics with natural and manmade shoreline features
Benthic, phytoplankton and zooplankton ecology
Coastal water and sediment quality, and ecosystem health
Benthic-pelagic coupling (physical and biogeochemical)
Interactions between physical dynamics (waves, currents, mixing, etc.) and biogeochemical cycles
Estuarine, coastal and shelf sea modelling and process studies.