Inter-specific and inter-individual trait variability matter in surface sediment reworking rates of intertidal benthic foraminifera

Abstract

Although benthic foraminifera are an important component of meiofauna and contribute to carbonate production and carbon/nitrogen cycles, their role in bioturbation processes remains poorly known. Five dominant intertidal benthic foraminifera were recently classified into functional bioturbator groups according to their sediment reworking mode and intensity. Our study aimed at identifying potential drivers (i.e. size and/or travelled distance) of speciesspecific surface sediment reworking rate. The travelled distance and surface sediment reworking rate of Haynesina germanica, Cribroelphidium williamsoni, Ammonia tepida, Quinqueloculina seminulum and Miliammina fusca were assessed through image analysis. Our

Foraminifera and plastic pollution: Knowledge gaps and research opportunities

“…Specifically, motion behavior is an acknowledged keystone process behind the success of foraging, mate-finding and habitat selection (Bowler and Benton 2005). Motion behavior is still, however, the forgotten child of foraminiferal ecology, despite its increasingly recognized variability Bouchet 2015, Jauffrais et al 2016) and role in bioturbation (Bouchet and Seuront 2020, Deldicq et al 2020, Deldicq et al 2021a). In addition, benthic foraminiferal behavior is affected in the presence of a stressor (gravity, organic matter, temperature; Seuront and Bouchet 2015, Jauffrais et al 2016, Deldicq et al 2021b) that may have further consequences on their search for food and for the optimal microhabitat.…”

“…They occupy a major trophic position through bacterivory, herbivory or carnivory (Nomaki et al 2008, Chronopoulou et al 2019. They also actively participate in the benthic ecosystem functioning via sediment mixing and bioirrigation, hence enhancing the fluxes of particulate and dissolved elements at the sediment-water interface (Bouchet and Seuront 2020, Deldicq et al 2020, Deldicq et al 2021a). In addition, foraminifera can accumulate large quantities of nitrate in their cell and reduce it through denitrification under low-oxygen conditions (Risgaard-Petersen et al 2006, Piña-Ochoa et al 2010; their contribution to the nitrogen cycle being, for instance, up to 70% in the North Sea (Piña-Ochoa et al 2010) or ranging from 50% to 100% in Swedish fjords (Choquel et al 2021).…”

Sediment reworking of intertidal sediments by the benthic foraminifera Haynesina germanica : the importance of motion behaviour and densities

“…In soft-bottom habitats, motion behaviour of intertidal foraminifera can generate horizontal displacement of sediment particles [28][29][30]. Some species may be involved in the vertical transport of sediment as they actively burrow in the sediment [30][31][32] either to reach their preferential microhabitat [33][34][35] or to escape after being buried by a storm or by macro-invertebrate bioturbation [36][37][38]. Such vertical movements may (i) have major impacts on the stability and erodibility of the surficial sediment layer [39,40], (ii) produce a substantial downward transport of particles and (iii) enhance fluxes of dissolved oxygen and solutes at the sediment-water interface [23,41].…”

“…In soft-bottom habitats, motion behaviour of intertidal foraminifera can generate horizontal displacement of sediment particles [28][29][30]. Some species may be involved in the vertical transport of sediment as they actively burrow in the sediment [30][31][32] either to reach their preferential microhabitat [33][34][35] or to escape after being buried by a storm or by macro-invertebrate bioturbation [36][37][38].…”

Domestic Sewage Outfall Severely Altered Environmental Conditions, Foraminiferal Communities, and Ecological Quality Statuses in Front of the Nearshore Beach of Cigarras (SE Brazil)

“…For example, benthic foraminifera are among the most important benthic organisms that can be used as bioindicators to assess anthropogenic effects on the environment [19][20][21], particularly in the case of water sewage [22][23][24]. Benthic foraminifera are abundant [25] and an important component of modern benthic communities, representing up to 50% of the benthic eukaryotic biomass [26], being a key link between microalgae and bacteria to the higher trophic levels [27,28] and playing a key role in bioturbation processes in soft-bottom sediments [29,30]. These organisms are sensitive to either natural or anthropogenic impacts (see review [31]), which constrain the assemblages composition, altering the abundance and diversity of organisms [22,32,33], leading to the formation of test anomalies [19,34,35], and favoring the development of opportunistic species due to their tolerance to pollutants and adverse environmental conditions [20,36,37].…”