Influence of the environmental characteristics of mangrove forests on recent benthic foraminifera in the Gulf of Urabá, Colombian Caribbean

Abstract

Mangrove forests with different characteristics have developed in the Gulf of Urabá (Colombia). Eighty-two sediment samples were studied for species of foraminifera and their environmental dependence. Ten agglutinated species and one calcareous species dominated in these mangroves. Foraminifera were absent in mangrove areas exposed to high hydraulic energy (waves) or high human affectation. Two characteristic assemblages were found. The first one, represented by Milliammina fusca, the most dominant species, was related to finer substrates and lower salinities. The second one, represented by Ammonia beccarii, the most common calcareous species, was found in polluted low-oxygen environments. Haplophragmoides canariensis and Trochammina squamata, small species, showed a preference for places with abundant organic matter. A conceptual model is proposed that relates the benthic foraminifera to the hydrodynamics, grain size, organic matter content, and pollution.

Estudo de caracterização geoquímica e das associações de foraminíferos parálicos do sistema estuarino do rio Jequitinhonha, litoral sul da Bahia

“…No período seco, a não ocorrência de foraminíferos se deve aos baixos valores de salinidade, os quais impossibilitaram a sobrevivência até mesmo das espécies mais resistentes (Gómes;Bernal, 2011) (Tabelas 1 e 3) Na estação chuvosa, os valores de riqueza variaram de 0,5 a 1,1; os de equitividade foram todos acima de 0,5, sugerindo a inexistência de dominância, como observado em estudos estatísticos com comunidades marinhas, realizados por Clarke e Warwick (2001). Os valores de diversidade oscilaram de 0,3 a 1,3 (Tabela 3), sendo estes considerados baixos quando comparados com aqueles obtidos por Gomes (2010) no estuário do rio Jacuípe-BA (1,0 a 4,4); por Teodoro (2009Teodoro ( e 2010 no Canal de São Sebastião, SP (0,3 a 2,8) e Araçá (2,4 a 2,9), também próximo ao Canal de São Sebastião-SP.…”

“…O aumento do número de foraminíferos pode ser atribuído ao aumento significativo da salinidade, o mesmo foi verificado por Martins et al (2010). Além disso, o predomínio da espécie H. wilberti, em ambos os períodos amostrais, deve-se à presença de ambientes compostos de sedimentação fina e ricos em nutrientes, típico de regiões de manguezal (Gómes;Bernal, 2011;Machado et al, 2012). Já o gênero Quinqueloculina é típico de ambientes arenosos e lamosos, corroborando com o elevado número de testas durante a primeira campanha, a qual apresentou predomínio de areia muito fina e silte (Lemos Júnior, 2011).…”

Unmixing Progradational Sediments in a Southwestern Caribbean Gulf through Late Holocene: Backwash of Low-Level Atmospheric Jets

“…Similarly, the mean sedimentation rate of the Amazon River was 0.5-1.15 cm/y during the Pleistocene and also dropped to 0.3 cm/y during the Holocene (Nitrouer et al, 1986). Alvarez and Bernal (2007), Bernal et al (2005), and Gómez and Bernal (2013) have reduced the sedimentary hiatus atop the León mouth core. They report that topset strata in Colombia Bay are devoid of benthic foraminifera owing to coarsened facies from medium silt to sand.…”

“…Studies at the Panama Isthmus in the Gulf of Urabá, where a narrow (130-km) strip of land separates the Atlantic and Pacific oceans, have been restricted either to surface circulation in the Recent epoch or anthropic effects on sediment yield and dispersion, as well as on benthic fauna (Álvarez and Bernal, 2007;Andrade and Barton, 2000;Andrade, Barton, and Mooers, 2003;Blanco, 2009;Correa, Alcá ntara-Carrió, and Gonzá lez, 2005;Gómez and Bernal, 2013;Montoya, 2010;Restrepo and Kjerfve, 2004;Restrepo et al, 2006;Vann, 1959). Moreover, there is little research on differentiating the effects of anthropic activities from natural variability on sedimentation through the late Holocene (Ospina, Palacio, and Vásquez, 2014;Rúa, Liebezeit, and Palacio, 2014).…”

Intertidal zonation of live benthic foraminiferal assemblages from mangrove environments around south-west Penang Island, Peninsular Malaysia

“…Species of benthic foraminifera in marshes/mangroves environments have been identified by some authors worldwide (e.g. Scott et al ., 2004; Woodroffe et al ., 2005; Murray, 2006; Berkeley et al ., 2009 a , 2009 b ; Culver et al ., 2012, 2013; Debenay, 2012; Gómez & Bernal, 2013; Satyanarayana et al ., 2014; Camacho et al ., 2015; Langer et al ., 2016). Common benthic foraminifera species that were found in mangrove ecosystems mostly consist of agglutinated taxa such as Ammotium morenoi , Arenoparrella mexicana , Haplophragmoides wilberti , Miliammina fusca , Entzia macrescens and Trochammina inflata , with some calcareous hyaline taxa (e.g.…”