Dockyards and harbors are recognized as being important locations where sediment-associated pollutants can accumulate, which constitutes an environmental risk to aquatic life due to potential uptake and accumulation of heavy metals in the biota. The aim of this paper is to assess the concentrations and the effects of some heavy metals in the benthic foraminifera assemblage in Niterói Harbor. Low concentrations in the benthic foraminifera as well as the dominance of indicative species such as Ammonia tepida, Buliminella elegantissima and Bolivina lowmani can be associated with an environment under stress. In addition, the occurrence of test abnormalities among foraminifera may represent a useful biomarker for evaluating long-term environmental impacts in a coastal region.

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Taphonomy focuses on the post-mortem processes of transport and preservation of biotic remains in the sedimentary record, and as such it has important applications for paleoenvironmental reconstructions. The aim of this work is to verify the degree of dissolution, abrasion, bioerosion and fragmentation in foraminiferal tests recovered from bottom sediments of the Parrachos de Maracajaú, Rio Grande do Norte, and to estimate the influence of these taphonomic processes in the distributon and preservation of the assemblages. Fifty-one species of benthic foraminifera have been found in the studied site. The taxonomic composition is typical of a coral reef environment. Amphistegina lessoni, Sorites marginalis, Quinqueloculina lamarckiana, Q. agglutinans, Peneroplis carinatus and Archaias angulatus are abundant in all the studied localities. The energy of the environment was interpreted as high. The species have been grouped into two groups, and the statistical data show that all four taphonomic processes (dissolution, abrasion, bioerosion and fragmentation) have influenced the distribution and preservation patterns of the foraminifera.

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