Morphological abnormalities of foraminiferal tests in Brazilian environments: comparison between polluted and non-polluted areas

Benthic foraminifera or Ostracoda? Comparing the accuracy of palaeoenvironmental indicators from a Pleistocene lagoon of the Romagna coastal plain (Italy)

“…Therefore, the high FAI recorded in the samples studied can be considered indicative of palaeoenvironmental stress, likely resulting from rapid oscillations in physico-chemical parameters such as salinity and oxygen concentration at the bottom. This is in accordance with other studies performed on benthic foraminiferal assemblages that interpret the high occurrence of abnormal specimens within transitional palaeoenvironments as a consequence of reduced, fluctuating salinity (Bik, 1964;Wang et al, 1985), oxygen depletion (Alve, 1991), or both (Geslin et al, 2002). Nevertheless, the contribution of other adverse ecological parameters could not be excluded since communities with high numbers of deformed tests generally result from the interplay of multiple environmental factors (Scott and Medioli, 1980;Boltovskoy et al, 1991).…”

“…Under stressed conditions, these microorganisms modify the community structure and develop a series of peculiar morphological abnormalities of the test (Alve, 1991). Abundant studies have been focused on the response of benthic foraminifera to anthropogenic pollution (Yanko et al, 1994;Alve, 1995;Armynot du Châtelet and Debenay, 2010;Frontalini and Coccioni, 2011), but foraminiferal abnormalities can also occur from natural stresses, such as extreme values of salinity, nutrients, oxygen, or very rapid changes in ecological parameters (Scott and Medioli, 1980;Almogi-Labin et al, 1992;Geslin et al, 2002). High concentrations of aberrant benthic foraminifera also occur in fossil assemblages, even though only a few cases are reported in the literature and are attributed to low or oscillating salinity (Bik, 1964;Bugrova, 1975;Wang et al, 1985).…”

“…As suggested by Boltovskoy et al (1991), the presence of highly deformed assemblages in both modern and fossil environments is not related to a single factor, but it may be produced by a series of ecological parameters. Although assessing which is the main ecological factor that led to the creation of deformities is generally difficult, the relative abundance of aberrant benthic foraminifera is a good proxy for palaeoenvironmental stress (Geslin et al, 2002).…”

Morphological Abnormalities and Dwarfism in Maastrichtian Foraminifera from the Cárdenas Formation, Valles–San Luis Potosí Platform, Mexico: evidence of paleoenvironmental stress

“…Recent studies have extensively documented foraminiferal test deformities from areas contaminated by heavy metals or other chemicals due to domestic sewage, and/or hydrocarbon spills (Resig, 1960;Alve, 1991;Yanko et al, 1998;Geslin et al, 1998;Samir, 2000;Geslin et al, 2002, Vilela et al, 2004Buzas-Stephens and Buzas, 2005;Meriç et al, 2005;Cevison and Hallock, 2007;Luciani, 2007;Fontalini and Coccioni, 2008;Polodova and Schönfeld, 2008;Madkour and Ali, 2008;Debenay et al, 2009;Martínez-Colón et al, 2009). However, it is important to emphasize that anthropogenic pollution is not always the cause of abnormal test formation (Stouf et al, 1999a).…”

Foraminíferos e atividade bacteriana aplicados no diagnóstico ambiental do estuário do rio Itacorubí, Florianópolis, SC

“…Altos percentuais de testas mal formadas podem estar relacionados a uma série de variáveis ambientais, assim como também a poluentes (Alve & Murray, 1995;Stouff et al, 1999;Geslin et al, 2002;Yanko et al, 1992Yanko et al, e 1994. A proximidade da estação IT 05 com o antigo aterro sanitário agrega a este trecho a presença de vários tensores ambientais, tais como vazamento de chorume, carbono bacteriano mais alto, dominância de processos metabólicos sulfato redutores, que podem ter contribuído para o maior número de testas mal formadas de A. mexicana.…”