Статті в журналах: "Haynesina germanica"

1

Jauffrais, Thierry, Bruno Jesus, Edouard Metzger, Jean-Luc Mouget, Frans Jorissen, and Emmanuelle Geslin. "Effect of light on photosynthetic efficiency of sequestered chloroplasts in intertidal benthic foraminifera (Haynesina germanica and Ammonia tepida)." Biogeosciences 13, no. 9 (May 10, 2016): 2715–26. http://dx.doi.org/10.5194/bg-13-2715-2016.

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Abstract. Some benthic foraminifera have the ability to incorporate functional chloroplasts from diatoms (kleptoplasty). Our objective was to investigate chloroplast functionality of two benthic foraminifera (Haynesina germanica and Ammonia tepida) exposed to different irradiance levels (0, 25, 70 µmol photon m−2 s−1) using spectral reflectance, epifluorescence observations, oxygen evolution and pulse amplitude modulated (PAM) fluorometry (maximum photosystem II quantum efficiency (Fv/Fm) and rapid light curves (RLC)). Our results clearly showed that H. germanica was capable of using its kleptoplasts for more than 1 week while A. tepida showed very limited kleptoplastic ability with maximum photosystem II quantum efficiency (Fv/Fm = 0.4), much lower than H. germanica and decreasing to zero in only 1 day. Only H. germanica showed net oxygen production with a compensation point at 24 µmol photon m−2 s−1 and a production up to 1000 pmol O2 cell−1 day−1 at 300 µmol photon m−2 s−1. Haynesina germanica Fv/Fm slowly decreased from 0.65 to 0.55 in 7 days when kept in darkness; however, it quickly decreased to 0.2 under high light. Kleptoplast functional time was thus estimated between 11 and 21 days in darkness and between 7 and 8 days at high light. These results emphasize that studies about foraminifera kleptoplasty must take into account light history. Additionally, this study showed that the kleptoplasts are unlikely to be completely functional, thus requiring continuous chloroplast resupply from foraminifera food source. The advantages of keeping functional chloroplasts are discussed but more information is needed to better understand foraminifera feeding strategies.

2

Goldstein, Susan T., and Elizabeth A. Richardson. "Fine structure of the foraminifer Haynesina germanica (Ehrenberg) and its sequestered chloroplasts." Marine Micropaleontology 138 (January 2018): 63–71. http://dx.doi.org/10.1016/j.marmicro.2017.10.010.

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3

Jauffrais, Thierry, Bruno Jesus, Vona Méléder, and Emmanuelle Geslin. "Functional xanthophyll cycle and pigment content of a kleptoplastic benthic foraminifer: Haynesina germanica." PLOS ONE 12, no. 2 (February 23, 2017): e0172678. http://dx.doi.org/10.1371/journal.pone.0172678.

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4

Wukovits, J., AJ Enge, P. Bukenberger, W. Wanek, M. Watzka, and P. Heinz. "Phytodetrital quality (C:N ratio) and temperature changes affect C and N cycling of the intertidal mixotrophic foraminifer Haynesina germanica." Aquatic Biology 30 (September 9, 2021): 119–32. http://dx.doi.org/10.3354/ab00746.

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The combination of lower diet quality and increased metabolic rates is assumed to cause cascading effects on organismic C cycling. Future changes in CO2 levels or terrestrial nutrient discharges in marine ecosystems can lead to increased phytoplankton C:N ratios relative to consumer C:N ratios, lowering the quality of the food source. In this study, we compared the single and interactive effects of diet quality and temperature on the feeding behavior and C and N intake and release of a common and abundant intertidal mixotrophic protist, the foraminifer Haynesina germanica. Two batches of artificially produced and dual isotope-labeled (13C/15N) chlorophyte detritus with different C:N ratios (5.6 and 7.1) were fed to the foraminifer at 3 different temperatures (15, 20, 25°C). We observed a strong interactive effect of temperature and diet. A very strong increase in feeding rates was observed at 20°C for the low-quality food source. Respiration rates of carbon derived from the low-quality diet (C:N ratio of 7.1) were lower than those of the high-quality diets and increased at 25°C. This indicates that a high C content of the diet might be of advantage in calcifying mixotrophs, since respired excess C could be advantageous for test calcification. Additionally, respired excess C could be a useful resource of CO2 for kleptoplast photosynthesis and functionality in the mixotrophic lifestyle of H. germanica. Further, the observed effects of diet and temperature could impact nutrient fluxes in the habitat of H. germanica, possibly leading to food-web shifts in the future.

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Langlet, Dewi, Vincent M. P. Bouchet, Camille Delaeter, and Laurent Seuront. "Motion behavior and metabolic response to microplastic leachates in the benthic foraminifera Haynesina germanica." Journal of Experimental Marine Biology and Ecology 529 (August 2020): 151395. http://dx.doi.org/10.1016/j.jembe.2020.151395.

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6

Castignetti, Paul. "A Time-Series Study of Foraminiferal Assemblages of the Plym Estuary, South-West England." Journal of the Marine Biological Association of the United Kingdom 76, no. 3 (August 1996): 569–78. http://dx.doi.org/10.1017/s0025315400031283.

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Monthly samples retrieved from the previously unstudied Plym Estuary, from January 1994 to November 1994, were analysed for living and dead Foraminifera. An assemblage composed of three hyaline species; Haynesina germanica, Elphidium williamsoni and Ammonia beccarii var. batavus, was identified. Further samples were taken to assess depth distribution, microdistribution and lateral distribution, to compliment the original sample suite. A comparison of the dead assemblage to the live assemblage revealed similar species proportions in both assemblages, reduced test abundance in the dead assemblage, and the presence of rare estuarine and marine species in the dead assemblage. This study has revealed a complex interplay of species resulting in several foraminiferal blooms throughout the year; the largest occurring in May.

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Lintner, Michael, Bianca Biedrawa, Julia Wukovits, Wolfgang Wanek, and Petra Heinz. "Salinity-dependent algae uptake and subsequent carbon and nitrogen metabolisms of two intertidal foraminifera (Ammonia tepida and Haynesina germanica)." Biogeosciences 17, no. 13 (July 16, 2020): 3723–32. http://dx.doi.org/10.5194/bg-17-3723-2020.

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Abstract. Benthic foraminifera are abundant marine protists which play an important role in the transfer of energy in the form of organic matter and nutrients to higher trophic levels. Due to their aquatic lifestyle, factors such as water temperature, salinity and pH are key drivers controlling biomass turnover through foraminifera. In this study the influence of salinity on the feeding activity of foraminifera was tested. Two species, Ammonia tepida and Haynesina germanica, were collected from a mudflat in northern Germany (Friedrichskoog) and cultured in the laboratory at 20 ∘C and a light–dark cycle of 16:08 h. A lyophilized algal powder from Dunaliella tertiolecta, which was isotopically enriched with 13C and 15N, was used as a food source. The feeding experiments were carried out at salinity levels of 11, 24 and 37 practical salinity units (PSU) and were terminated after 1, 5 and 14 d. The quantification of isotope incorporation was carried out by isotope ratio mass spectrometry. Ammonia tepida exhibited a 10-fold higher food uptake compared to H. germanica. Furthermore, in A. tepida the food uptake increased with increasing salinity but not in H. germanica. Over time (from 1–5 to 14 d) food C retention increased relative to food N in A. tepida while the opposite was observed for H. germanica. This shows that if the salinity in the German Wadden Sea increases, A. tepida is predicted to exhibit a higher C and N uptake and turnover than H. germanica, with accompanying changes in C and N cycling through the foraminiferal community. The results of this study show how complex and differently food C and N processing of foraminiferal species respond to time and to environmental conditions such as salinity.

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Wukovits, Julia, Annekatrin Julie Enge, Wolfgang Wanek, Margarete Watzka, and Petra Heinz. "Increased temperature causes different carbon and nitrogen processing patterns in two common intertidal foraminifera (Ammonia tepida and Haynesina germanica)." Biogeosciences 14, no. 11 (June 9, 2017): 2815–29. http://dx.doi.org/10.5194/bg-14-2815-2017.

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Abstract. Benthic foraminifera are highly abundant heterotrophic protists in marine sediments, but future environmental changes will challenge the tolerance limits of intertidal species. Metabolic rates and physiological processes in foraminifera are strongly dependent on environmental temperatures. Temperature-related stress could therefore impact foraminiferal food source processing efficiency and might result in altered nutrient fluxes through the intertidal food web. In this study, we performed a laboratory feeding experiment on Ammonia tepida and Haynesina germanica, two dominant foraminiferal species of the German Wadden Sea/Friedrichskoog, to test the effect of temperature on phytodetritus retention. The specimens were fed with 13C and 15N labelled freeze-dried Dunaliella tertiolecta (green algae) at the start of the experiment and were incubated at 20, 25 and 30 °C respectively. Dual labelling was applied to observe potential temperature effects on the relation of phytodetrital carbon and nitrogen retention. Samples were taken over a period of 2 weeks. Foraminiferal cytoplasm was isotopically analysed to investigate differences in carbon and nitrogen uptake derived from the food source. Both species showed a positive response to the provided food source, but carbon uptake rates of A. tepida were 10-fold higher compared to those of H. germanica. Increased temperatures had a far stronger impact on the carbon uptake of H. germanica than on A. tepida. A distinct increase in the levels of phytodetrital-derived nitrogen (compared to more steady carbon levels) could be observed over the course of the experiment in both species. The results suggest that higher temperatures have a significant negative effect on the carbon exploitation of H. germanica. For A. tepida, higher carbon uptake rates and the enhanced tolerance range for higher temperatures could outline an advantage in warmer periods if the main food source consists of chlorophyte phytodetritus. These conditions are likely to impact nutrient fluxes in A. tepida/H. germanica associations.

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Goldstein, Susan T., Joan M. Bernhard, and Elizabeth A. Richardson. "Chloroplast Sequestration in the Foraminifer Haynesina germanica: Application of High Pressure Freezing and Freeze Substitution." Microscopy and Microanalysis 10, S02 (August 2004): 1458–59. http://dx.doi.org/10.1017/s1431927604885891.

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10

Deldicq, N., L. Seuront, D. Langlet, and VMP Bouchet. "Assessing behavioural traits of benthic foraminifera: implications for sediment mixing." Marine Ecology Progress Series 643 (June 11, 2020): 21–31. http://dx.doi.org/10.3354/meps13334.

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The assessment of behavioural traits of marine organisms is increasingly recognized as a key issue to understanding their role in ecosystem processes such as bioturbation and nutrient cycling. The movement ability of intertidal foraminifera suggest that they may have a role, yet to be quantified, in benthic-pelagic coupling through their movement on the sediment surface, at the sediment-water interface and within the sediment. In this context, we investigated the behavioural traits of 5 benthic foraminiferal species typical of European temperate mudflats under standardized trophic light and temperature conditions. Behavioural traits related to motion of Ammonia tepida, Haynesina germanica, Cribroelphidium williamsoni, Miliammina fusca and Quinqueloculina seminula were assessed through their travelled distance, velocity, tortuosity of the path, position in the sediment and activity index. By analogy with macrofauna bioturbation functional groups, we describe the studied foraminifera as biodiffusor species with 3 sub-groups defined according to their vertical position in the sediment. C. williamsoni belongs to the epifaunal-biodiffusors, A. tepida and H. germanica belong to the surficial-biodiffusors, and Q. seminula and M. fusca are considered gallery-biodiffusors. Our results further suggest that features such as velocity, activity and tortuosity may mediate sediment-mixing intensity. Therefore, Q. seminula, H. germanica and C. williamsoni, which are the most active species, would have a larger effect on particle reworking rates than the less active A. tepida and M. fusca. Our results suggest that benthic foraminifera may play an underestimated role in bioturbation processes.

11

Calvo-Marcilese, Lydia, and Martin R. Langer. "Breaching biogeographic barriers: the invasion of Haynesina germanica (Foraminifera, Protista) in the Bahía Blanca estuary, Argentina." Biological Invasions 12, no. 9 (February 26, 2010): 3299–306. http://dx.doi.org/10.1007/s10530-010-9723-x.

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12

Wukovits, Julia, Max Oberrauch, Annekatrin J. Enge, and Petra Heinz. "The distinct roles of two intertidal foraminiferal species in phytodetrital carbon and nitrogen fluxes – results from laboratory feeding experiments." Biogeosciences 15, no. 20 (October 23, 2018): 6185–98. http://dx.doi.org/10.5194/bg-15-6185-2018.

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Abstract. Benthic foraminifera play a major role as primary consumers and detrivores redistributing organic carbon and nitrogen in intertidal environments. Here we compared the differences of phytodetrital carbon and nitrogen intake and turnover of two dominant intertidal foraminifera, Ammonia tepida and Haynesina germanica. Their lifestyles in relation to feeding behavior (feeding preferences, intake and turnover of phytodetrital carbon and nitrogen) and temperature adaptations were compared to obtain a closer definition of their specific roles in intertidal organic matter processing. For this comparison, we carried out a series of short-term laboratory incubations with stable-isotope-labeled (13C and 15N) detritus as the food source. We compared the response of the two species to diatom detritus at three different temperatures (15, 20, 25 ∘C). Ammonia tepida showed a very high, temperature-influenced intake and turnover rates with more excessive carbon turnover, compared to nitrogen. The fairly low metabolic nitrogen turnover in H. germanica was not affected by temperature and was higher than the carbon turnover. This might be related with the chloroplast husbandry in H. germanica and its lower demands for food-derived nitrogen sources. Ammonia tepida prefers a soft chlorophyte food source over diatom detritus, which is harder to break down. In conclusion, A. tepida shows a generalist behavior that links with high fluxes of organic matter (OM). Due to its high rates of OM processing and abundances, we conclude that A. tepida is an important key player in intertidal carbon and nitrogen turnover, specifically in the short-term processing of OM and the mediation of dissolved nutrients to associated microbes and primary producers. In contrast, H. germanica is a highly specialized species with low rates of carbon and nitrogen budgeting.

13

Jesus, Bruno, Thierry Jauffrais, Erik C. L. Trampe, Johannes W. Goessling, Charlotte Lekieffre, Anders Meibom, Michael Kühl, and Emmanuelle Geslin. "Kleptoplast distribution, photosynthetic efficiency and sequestration mechanisms in intertidal benthic foraminifera." ISME Journal 16, no. 3 (October 11, 2021): 822–32. http://dx.doi.org/10.1038/s41396-021-01128-0.

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AbstractForaminifera are ubiquitously distributed in marine habitats, playing a major role in marine sediment carbon sequestration and the nitrogen cycle. They exhibit a wide diversity of feeding and behavioural strategies (heterotrophy, autotrophy and mixotrophy), including species with the ability of sequestering intact functional chloroplasts from their microalgal food source (kleptoplastidy), resulting in a mixotrophic lifestyle. The mechanisms by which kleptoplasts are integrated and kept functional inside foraminiferal cytosol are poorly known. In our study, we investigated relationships between feeding strategies, kleptoplast spatial distribution and photosynthetic functionality in two shallow-water benthic foraminifera (Haynesina germanica and Elphidium williamsoni), both species feeding on benthic diatoms. We used a combination of observations of foraminiferal feeding behaviour, test morphology, cytological TEM-based observations and HPLC pigment analysis, with non-destructive, single-cell level imaging of kleptoplast spatial distribution and PSII quantum efficiency. The two species showed different feeding strategies, with H. germanica removing diatom content at the foraminifer’s apertural region and E. williamsoni on the dorsal site. All E. williamsoni parameters showed that this species has higher autotrophic capacity albeit both feeding on benthic diatoms. This might represent two different stages in the evolutionary process of establishing a permanent symbiotic relationship, or may reflect different trophic strategies.

14

Poirier, Clément, Juliette Baumann, and Eric Chaumillon. "Hypothetical Influence of Bacterial Communities on the Transfer of 14C-Depleted Carbon to Infaunal Foraminifera: Implications for Radiocarbon Dating in Coastal Environments." Radiocarbon 61, no. 03 (May 20, 2019): 845–65. http://dx.doi.org/10.1017/rdc.2019.7.

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ABSTRACTLittle is known about the potential complications that may arise from the use of coastal foraminifera for radiocarbon (14C) dating. The aim of this study is to report the fortuitous finding of 14C-dated Haynesina germanica individuals picked from two sediment cores (Pertuis Charentais, France), which appeared 2500–2000 years older than their expected age of deposition. Stratigraphical and micropaleontogical evidence have ruled out the possible effect of reworking of calcareous tests from previous strata. Similar anomalous 14C ages were obtained on abundant lignocellulose debris recovered from the cores, which are supplied by rivers flowing into the study area. Given that H. germanica is an infaunal species, we hypothesize that in-situ living individuals acquired the 14C-depleted isotopic signature of lignocellulose debris within the sediment prior to definitive burial, following an unexplored pathway of carbon transfer between the two compartments. Based on the literature, we propose a plausible explanation, which involves bacterial communities living in the study area. This putative role of bacteria may have considerable importance for past and future studies of Holocene environmental changes in coastal environments. Further work is now needed to explore this hypothesis with more robust, direct evidence based on comprehensive geochemical, geochronological and microbiological studies.

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BERGAMIN, I., E. ROMANO, M. GABELLINI, A. AUSILI, and M. G. CARBONI. "Chemical-physical and ecological characterisation in the environmental project of a polluted coastal area: the Bagnoli case study." Mediterranean Marine Science 4, no. 2 (December 1, 2003): 5. http://dx.doi.org/10.12681/mms.225.

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The Bagnoli Bay (southern Tyrrhenian Sea, Naples, Italy) has been impacted for about one century by heavy anthropogenic pollution due to an important steel plant. A multidisciplinary environmental research, aimed at the reclamation of the marine contaminated area, was planned in order to evaluate, through quantitative data, the chemical-physical and ecological characteristics of marine sediments; the latter ones are strictly related to the composition and structure of benthic foraminiferal assemblages. A comprehensive statistical approach, considering all data, was attempted in order to single out the influence of pollutants on the single species distribution. The results show strong heavy metal pollution (Fe, Mn, Pb and Zn) in the vicinity of the industrial plant. Many foraminiferal species (Haynesina germanica, Miliolinella subrotunda,Quinqueloculina parvula), have a good tolerance to some trace metals while, Bulimina sublimbata, Elphidiummacellum and Miliolinella dilatata show a good tolerance to PAHs pollution.

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Wilson, Brent, and Benjamin P. Horton. "Determining carrying capacity from foraminiferal time-series." Journal of Micropalaeontology 31, no. 2 (July 1, 2012): 111–19. http://dx.doi.org/10.1144/0262-821x11-009.

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Abstract. The carrying capacity K is the equilibrium population density of a species that an area can support while adequately meeting the needs of every individual. Although widely used in ecology, it has yet to be applied rigorously to living foraminifera. K is readily determined from time-series of population densities. Given that Nt+1 = Nt + RNt, in which Nt is the population densities at time t, Nt+1 is the density at a subsequent time t+1 and R is the per capita rate of change in population density, then linear regression gives Rt = Rm − sNt, in which Rt is the per capita rate of increase at time t, the constant Rm is the maximum possible individual rate of increase, and the negative slope s represents the strength of intraspecific interactions. Setting Rt = 0, so that Nt = K and Rm – sK = 0, gives K = Rm/s, which is applicable in aseasonal environments. There are two carrying capacities in seasonal environments, depending on whether the season is favourable (Kmax) or unfavourable (Kmin). Values of Kmax and Kmin are estimated for Nonion depressulus in the Exe estuary, UK (25 monthly samples), Quinqueloculina spp. in the Indian River Lagoon, USA (60 monthly samples) and Haynesina germanica in Cowpen Marsh, UK (25 fortnightly samples). The most precise estimate was for H. germanica, but it was unclear if this was due to the high rate of sampling or the large number of replicates used to erect this time-series.

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Austin, Heather Anne, William E. N. Austin, and David M. Paterson. "Extracellular cracking and content removal of the benthic diatom Pleurosigma angulatum (Quekett) by the benthic foraminifera Haynesina germanica (Ehrenberg)." Marine Micropaleontology 57, no. 3-4 (December 2005): 68–73. http://dx.doi.org/10.1016/j.marmicro.2005.07.002.

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Diz, P., F. J. Jorissen, G. J. Reichart, C. Poulain, F. Dehairs, E. Leorri, and Y. M. Paulet. "Interpretation of benthic foraminiferal stable isotopes in subtidal estuarine environments." Biogeosciences Discussions 6, no. 4 (July 24, 2009): 7453–80. http://dx.doi.org/10.5194/bgd-6-7453-2009.

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Abstract. Here we present a novel approach for the interpretation of stable isotope signatures recorded in benthic foraminifera from subtidal estuarine environments. The stable isotopic composition (δ18O and δ13C) of living Ammonia tepida and Haynesina germanica is examined in four stations in the Auray River estuary (Gulf of Morbihan, France) sampled in two contrasting seasons, spring 2006 and winter 2007. Comparing benthic foraminiferal δ18O measurements with theoretical oxygen isotopic equilibrium values, calculated on the basis of water temperature and salinity measurements in the upper and lower estuary, i.e., T−S−δ18Oeq. diagrams, strongly suggests that foraminiferal faunas sampled at the four stations calcified during different periods of the year. This interpretation can be refined by using the benthic foraminiferal δ13C which is mainly determined by the mixing of sea and river water. In the upper estuary foraminifera mainly calcified in early spring and winter, whereas in the lower estuary calcification took mainly place in spring, summer and autumn. This new method provides insight into the complexity of estuarine benthic foraminiferal stable isotope records. In addition, it can also be used to obtain new information on preferred calcification periods of benthic foraminiferal taxa in different parts of the estuary.

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Diz, P., F. J. Jorissen, G. J. Reichart, C. Poulain, F. Dehairs, E. Leorri, and Y. M. Paulet. "Interpretation of benthic foraminiferal stable isotopes in subtidal estuarine environments." Biogeosciences 6, no. 11 (November 13, 2009): 2549–60. http://dx.doi.org/10.5194/bg-6-2549-2009.

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Abstract. Here we present a novel approach for the interpretation of stable isotope signatures recorded in benthic foraminifera from subtidal estuarine environments. The stable isotopic composition (δ18O and δ13C) of living Ammonia tepida and Haynesina germanica is examined at four stations in the Auray River estuary (Gulf of Morbihan, France) sampled in two contrasting seasons, spring 2006 and winter 2007. Comparing benthic foraminiferal δ18O measurements with theoretical oxygen isotopic equilibrium values, calculated on the basis of water temperature and salinity measurements in the upper and lower estuary, i.e., T-S-δ18Oeq. diagrams, strongly suggests that foraminiferal faunas sampled at the four stations calcified during different periods of the year. This interpretation can be refined by using the benthic foraminiferal δ13C, which is mainly determined by the mixing of sea and river water. In the upper estuary foraminifera mainly calcified in early spring and winter, whereas in the lower estuary calcification mainly took place in spring, summer and autumn. This new method provides insight into the complexity of estuarine benthic foraminiferal stable isotope records. In addition, it can also be used to obtain new information on preferred calcification periods of benthic foraminiferal taxa in different parts of the estuary.

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Langer, Martin R. "Comparative molecular analysis of small-subunit ribosomal 18S DNA sequences from Haynesina germanica (Ehrenberg, 1840), a common intertidal foraminifer from the North Sea." Neues Jahrbuch für Geologie und Paläontologie - Monatshefte 2000, no. 11 (October 13, 2000): 641–50. http://dx.doi.org/10.1127/njgpm/2000/2000/641.

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Guilhermic, Corentin, Maria Pia Nardelli, Aurélia Mouret, Damien Le Moigne, and Hélène Howa. "Short-term response of benthic foraminifera to fine-sediment depositional events simulated in microcosm." Biogeosciences 20, no. 15 (August 11, 2023): 3329–51. http://dx.doi.org/10.5194/bg-20-3329-2023.

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Abstract. A microcosm experiment was designed to describe how benthic foraminifera react to fine-sediment deposits varying in frequency and intensity as they may occur regularly or occasionally in coastal benthic environments, caused by discharges from (e.g.) river flooding, tidewater glacier melting in polar regions, or diverse anthropic activities linked to harbour or watershed management. The influence of seabed burial resulting from these events on the ecology of benthic ecosystems is often overlooked, and the resilience of benthic communities is poorly known. During a 51 d long experiment, a typical northeastern Atlantic intertidal foraminiferal community, mainly represented by Ammonia confertitesta and Haynesina germanica species, was subjected to two kinds of sedimentary disturbance: (1) a one-time high-volume (OHV) deposit, i.e. sediment about 3 cm thick was added at one time at the beginning of the experiment; and (2) frequent low-volume (FLV) deposits, i.e. sediment about 0.5 cm thick was added each week for 4 weeks. The geochemical environment (e.g. dissolved oxygen penetration in the sediment, salinity, temperature, and nutrient content in the supernatant water) was monitored to follow the microcosm steady state before and during the experiment. In both disturbed microcosms, H. germanica showed a significant linear decrease in abundance during the experiment, while the total abundance of foraminifera was significantly affected only by the OHV treatment, suggesting a stronger effect of a single thick deposit on standing stocks and biodiversity compared to frequent low-volume sediment supplies. Concerning the vertical migration of foraminifera after sedimentary disturbances, the two dominant species moved upwards to the water–sediment interface with migration speeds estimated to be 0.41 and 0.47 mm h−1 respectively for A. confertitesta and H. germanica. In the FLV treatment, the resilient state was already reached within 1 d following a low-thickness burial, while in the OHV, it was achieved between 1 and 7 d after the 3 cm thick deposit. These results suggest that foraminifera can migrate rapidly after a sedimentary burial to recover their preferential life position under the new sediment–water interface, but in the case of an abrupt thick burial, several days are needed to reach a resilient state.

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Smith, Christopher W., and Susan T. Goldstein. "The Effects of Selected Heavy Metal Elements (arsenic, Cadmium, Nickel, Zinc) On Experimentally Grown Foraminiferal Assemblages from Sapelo Island, Georgia and Little Duck Key, Florida, U.S.A." Journal of Foraminiferal Research 49, no. 3 (July 1, 2019): 303–17. http://dx.doi.org/10.2113/gsjfr.49.3.303.

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Abstract Benthic foraminifera are valuable environmental indicators of heavy metal contaminants in marine environments. To broaden their effectiveness as bioindicators, this study compares individually the effects of selected heavy metal contaminants, including both metabolically essential and non-essential elements, on temperate rotalids and subtropical miliolids, as well as associated monothalamid foraminifera. To accomplish these aims, assemblages of foraminifera were grown experimentally from propagules (small juveniles) collected from two coastal sites: Sapelo Island, Georgia, and Little Duck Key, Florida, that provide an effective comparison between environments and types of foraminifera. Surface sediment was collected from both locations and sieved immediately after collection. Using the propagule method, assemblages of foraminifera were grown in the laboratory from propagules in the sediment samples. Two metabolically essential trace elements, nickel, and zinc, and two non-essential elements, arsenic and cadmium were used to represent both types of heavy metal. Experimental conditions were held constant while varying only the metal concentrations. In treatments from both origins, increasing concentrations of cadmium, nickel, and zinc led to decreases in abundance and diversity for the foraminifera. In addition, zinc, and to a lesser extent cadmium and nickel above certain concentrations, resulted in an increase of deformed tests among the foraminifera. Deformities occurred amongst the most common calcareous species from Sapelo island: Ammonia tepida and Haynesina germanica. Fewer deformities were observed in common calcareous species from Little Duck Key, the miliolids Quinqueloculina sabulosa and Quinqueloculina bosciana featured few deformities. Notably, monothalamid species such as Psammophaga sapela remained present at high metal concentrations. These results support previous research and reinforce the usefulness of rotalids such as A. tepida and H. germanica as bioindicators of heavy metal contamination as well as suggesting a possible use of monothalamids such as P. sapela in this manner.

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du Chatelet, Eric Armynot, Delphine Degre, Pierre-Guy Sauriau, and Jean-Pierre Debenay. "Distribution of living benthic foraminifera in relation with environmental variables within the Aiguillon cove (Atlantic coast, France): improving knowledge for paleoecological interpretation." Bulletin de la Société Géologique de France 180, no. 2 (March 1, 2009): 131–44. http://dx.doi.org/10.2113/gssgfbull.180.2.131.

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Abstract Search for bioindicators in marine environments has provided new tools for monitoring global and local natural changes. Among these tools, benthic foraminifera play a central role. More accurate paleogeographical and paleoecological reconstructions become possible on the basis of the ecology of recent foraminifera. Nevertheless, factors acting on foraminiferal assemblages are still partially understood. The aim of this study is to correlate the distribution patterns of living (stained) benthic foraminifera with environmental variables such as tidal elevation, interstitial pore water salinity, organic matter content of the sediment, pheopigments, chlorophyll a, carbonate contents and grain size distribution of the sediment from 86 samples collected in the Aiguillon cove (France). In this paralic environment, sediment grain size, salinity and tidal elevation are fundamental factors that drive the distribution of the most abundant species i.e. Brizalina variabilis, Cribroelphidium excavatum and Haynesina germanica. Organic matter also influences the distribution patterns of benthic foraminifera: the relative abundance of Ammonia tepida is typically favored by an increase of total organic matter food resources. Chlorophyll a and pheopigments, as indicators of organic matter quality however may not be limiting in the proportion present in the Aiguillon cove. Carbonate proportions do not limit benthic foraminifera of the Aiguillon cove essentially with carbonaceous shells.

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Rodríguez-Pérez, Ana, Ana María Blázquez, Jordi Guillem, and Juan Usera. "Maximum flood area during MIS 1 in the Almenara marshland (Western Mediterranean): Benthic foraminifera and sedimentary record." Holocene 28, no. 9 (May 31, 2018): 1452–66. http://dx.doi.org/10.1177/0959683618777069.

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The sedimentological and micropaleontological analysis of three mechanical cores in the marshland of Almenara (Valencian Community, Spain) has allowed the reconstruction of the Holocene evolution of this wetland. The cold and dry 8.2-ka event might be represented in Almenara by a massive carbonate precipitation bed, upon which mid- and late-Holocene sediments were subsequently deposited. The direct influence of sea-level changes has been recorded in the two cores (S-4 and S-5) located near the marsh barrier, at 400–450 m from the current coastline. The maximum flood area during MIS 1 (last 11,600 years) is represented in these cores by sediments indicative of different littoral subenvironments (shoreface, foreshore, backshore). These sediments contain typically littoral marine foraminiferal species such as Ammonia beccarii, Rosalina globularis, Asterigerinata mamilla, Adelosina longirostra, Cibicidoides lobatulus, Elphidium macellum, and Bolivina pseudoplicata. The base of these littoral sedimentary materials has been dated as 5480 and 5580 cal. yr BP. At this moment, the inner area (core S-7) was occupied by a restricted oligohaline marsh subject to water-table fluctuations and with scarce individuals of brackish water foraminifera, such as Ammonia tepida, Haynesina germanica, or Cribroelphidium excavatum, that in more recent times (since at least 1700 cal. yr BP) gradually evolved to a palustrine area.

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Swallow, Jane E. "Intra-annual variability and patchiness in living assemblages of salt-marsh foraminifera from Mill Rythe Creek, Chichester Harbour, England." Journal of Micropalaeontology 19, no. 1 (May 1, 2000): 9–22. http://dx.doi.org/10.1144/jm.19.1.9.

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Abstract. The areas of coastal marsh studied in Mill Rythe Creek, Chichester Harbour, southern England, support a fluctuating foraminiferal assemblage which, although similar to those recorded in other parts of the UK and the Atlantic seaboard of North America, has its own distinctive assemblage of species. This is due to the constantly high salinity of the water here. Unusually, these marshes do not receive freshwater input from a nearby river and thus are not subject to tidal fluctuations in salinity.The mid-marsh Site 1 has a fauna consisting of typical marsh species, e.g., Jadammina macrescens, Trochammina inflata and Miliammina fusca. In addition, normal marine salinity allows Quinqueloculina oblonga to flourish and even dominate the fauna in most samples. The lower marsh Site 2 contains a typical marsh fauna dominated by hyaline forms. The dominance of Ammonia beccarii [aberdoveyensis] is most characteristic of the lower marsh, together with Haynesina germanica. The normal marine salinity of the marsh can again be confirmed by the high abundance of Quinqueloculina oblonga.The results of a replicate sampling regime employed in this study clearly demonstrate the patchy nature of the living foraminiferal distribution in marsh environments over small lateral distances as well as the high seasonal variability of foraminiferal abundances.

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Ellis, Alisha M., Jaimie E. Shaw, Lisa E. Osterman, and Christopher G. ,. Smith. "The Foraminifera of Chincoteague Bay, Assateague Island, and the Surrounding Areas: a Regional Distribution Study." Journal of Foraminiferal Research 48, no. 3 (July 2, 2018): 223–40. http://dx.doi.org/10.2113/gsjfr.48.3.223.

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Abstract Foraminiferal census data from Chincoteague Bay, Newport Bay, the salt marshes of Assateague Island, adjacent mainland salt marshes, and the inner-shelf, were assessed to determine the current assemblages in Chincoteague Bay, and how the different environments surrounding the bay, and the gradients within the bay, influence the microfossil distribution. Determining the current background distribution and its drivers allows for future comparisons to determine paleoenvironmental conditions, impacts from natural and anthropogenic pollution, and the influence of climate change. Foraminiferal census data were compared to sedimentological characteristics and environmental parameters, exhibiting strong correlations with salinity, sediment organic content, and grain-size. Foraminiferal distributions exhibited a gradient from an assemblage dominated by Elphidium cf. E. excavatum near Chincoteague inlet to an assemblage dominated by Ammonia parkinsoniana and Ammobaculites cf. Ab. exiguus in the more restricted central and northern portions of the bay. The sites closest to the mouth of Trappe Creek in Newport Bay, along the western side of Chincoteague Bay and in the central bay, had a greater relative abundance of dead agglutinated taxa compared with the majority of sites in Chincoteague Bay. Despite the overwhelming dominance of calcareous taxa throughout the bay, dissolution may affect the preservation potential of Cribroelphidium poeyanum and Haynesina germanica in the northern and central portions of Chincoteague Bay, as indicated by seasonal pH data. Similarly, the sandy back-barrier lagoonal sites exhibited relatively low densities, potentially a result of dissolution or mechanical destruction.

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Fouet, Marie P. A., David Singer, Alexandra Coynel, Swann Héliot, Hélène Howa, Julie Lalande, Aurélia Mouret, Magali Schweizer, Guillaume Tcherkez, and Frans J. Jorissen. "Foraminiferal Distribution in Two Estuarine Intertidal Mudflats of the French Atlantic Coast: Testing the Marine Influence Index." Water 14, no. 4 (February 18, 2022): 645. http://dx.doi.org/10.3390/w14040645.

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This study focuses on the foraminiferal distribution on intertidal mudflats of two contrasted estuaries (Auray and Vie) along the French Atlantic coast. In both estuaries, the foraminiferal communities are dominated by Haynesina germanica and the Ammonia tepida group. Stations located near the outlets show a high diversity and abundance of species of the genus Elphidium. Stations in the inner estuary show a higher proportion of agglutinated species (Ammotium salsum, Ammobaculites agglutinans). Multivariate statistical analysis suggests that the distance to the sea and the percentage of fine sediment (<63 µm) are the two main parameters explaining the foraminiferal distribution. Chemical analyses of the sediment show that the two studied estuaries are not affected by major anthropogenic pollution, so that the faunas should mainly reflect the natural controlling parameters. Three indices of environmental quality commonly used in coastal areas show counter-intuitive differences between stations, suggesting that these indices may be less reliable for use in intertidal estuarine mudflats. The newly developed Marine Influence Index (MII) integrates three major ecological factors: the position of the sampling point on the salinity gradient, the emergence time at low tide and the relative importance of fresh water discharge. In our dataset, MII shows significant correlations with the controlling environmental parameters (distance to the sea, percentage grains < 63 µm), as well as with the foraminiferal patterns (PCA axis 1, species richness, percentage of Elphidium spp. and Quinqueloculina spp.). These results suggest that the MII explains a substantial part of the faunal variability on estuarine intertidal mudflats, and can be used to detect deviations from the natural distribution patterns in response to anthropogenic pollution.

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Daviray, Maxime, Emmanuelle Geslin, Nils Risgaard-Petersen, Vincent V. Scholz, Marie Fouet, and Edouard Metzger. "Potential impacts of cable bacteria activity on hard-shelled benthic foraminifera: implications for their interpretation as bioindicators or paleoproxies." Biogeosciences 21, no. 4 (February 20, 2024): 911–28. http://dx.doi.org/10.5194/bg-21-911-2024.

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Abstract. Hard-shelled foraminifera are protists able to build a calcareous or agglutinated shell (called a “test”). Here we study the impact of sediment acidification on calcareous test preservation. For this study, sediment cores were sampled in the macrotidal Auray estuary located on the French Atlantic coast. Living and dead foraminifera were quantified until 5 cm depth and discriminated using the Cell-Tracker™ Green vital marker. The pH and oxygen profiles combined with quantitative polymerase chain reaction (qPCR) suggested that cable bacteria were most likely to cause the acidifying process. Cable bacteria (CB) are filamentous bacteria coupling sulfide oxidation to oxygen reduction over centimetre distances, generating a strong pH gradient within the first few centimetres of the sediment that could affect the microhabitats occupied by benthic foraminifera. On two different intertidal mudflats, volumetric filament densities have been estimated. They were comparable to those observed in the literature for coastal environments, with 7.4 ± 0.4 and 74.4 ± 5.0 m cm−3 per bulk sediment, respectively. Highly contrasting sediment acidification (from low to very intense) was described from 1.0 to 2.4 ΔpH. This seems to lead to various dissolution stages of the foraminiferal calcareous test from intact to fully dissolved tests revealing the organic lining. The dissolution scale is based on observations of living Ammonia spp. and Haynesina germanica specimens under a scanning electronic microscope. Furthermore, dead foraminiferal assemblages showed a strong calcareous test loss and an organic lining accumulation throughout depth under low pH, hampering the test preservation in deep sediment. These changes in both living and dead foraminiferal assemblages suggest that cable bacteria must be considered in ecological monitoring and historical studies using foraminifera as bioindicators and paleoenvironmental proxies.

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Fatela, Francisco, João Moreno, and M. Cristina Cabral. "Salinity and water temperature assessment of the tidal marshes from the W Portuguese coast, as an ecological tool to palaeoenvironmental reconstructions based on Foraminifera and Ostracoda assemblages." Estudos do Quaternário / Quaternary Studies, no. 14 (June 22, 2016): 73–81. http://dx.doi.org/10.30893/eq.v0i14.124.

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A seasonal study of temperature and salinity of estuarine and sediment interstitial water of tidal marshes was undertaken along three estuaries of W Portuguese coast (Minho, Tejo and Mira).The climatic N-S transition from wet Atlantic to Mediterranean features appear clearly imprinted in the distribution of tidal marsh assemblages, like foraminifera and ostracoda, mainly reflecting the water salinity gradient control.The Minho low estuary tidal marsh tends to be flooded by estuarine water ranging from 0.5‰ to 32‰ in each tide cycle, even during dry seasons. However, the marsh hydrological balance sustains a more stable environment where the salinity of interstitial water measurements yielded 8‰ to 16‰. In contrast the Tejo and Mira salt marsh flooding waters record a narrow range between 33‰ and 36‰, in spring, and between 29‰ and 36‰ in autumn. The climatic control of evaporation/ precipitation balance produces an enhanced salinity of marsh interstitial water, that can reach hypersaline conditions, with maximum records of 53‰ in Tejo and 48‰ in Mira lower estuaries.These environmental differences along the W Portuguese coast are recorded by the tidal marsh assemblages, namely foraminifera and ostracoda. In the low salinity Caminha salt marsh, living foraminifera are essentially composed by the agglutinated species Haplophragmoides manilaensis, Miliammina fusca, Pseudothurammina limnetis Psammosphaera sp. and Trochamminita salsa. The modern ostracoda assemblage includes Leptochytere baltica, Leptochytere psammophila, Leptocythere sp. A and Tuberoloxoconcha sp.1. In the Tejo and Mira salt marsh Ammonia beccarii, Ammonia tepida, Haynesina germanica, Jadammina macrescens, Trochammina inflata, are the dominant foraminifera and Loxoconcha malcomsoni, Terrestricythere cf. elisabethae, Tuberoloxoconcha cf. atlantica and Xestoleberis labiata prevail as well as many other more marine ostracoda species, such as Basslerites teres and Leptocythere fabaeformis.This study highlights that the knowledge of driven ecological parameters of modern assemblages (usually preserved in fossil record), is fundamental to support reliable paleoclimatic and palaeoenvironmental reconstructions.

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Camacho, Sarita, Tomasz Boski, Delminda Moura, David Scott, Simon Connor, and Laura Pereira. "Paleoenvironmental evolution of the Guadiana Estuary, Portugal, during the Holocene: A modern foraminifera analog approach." Holocene 27, no. 2 (August 4, 2016): 197–235. http://dx.doi.org/10.1177/0959683616658526.

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In this paper, we reconstruct the Holocene paleoenvironmental evolution of the Guadiana Estuary, southwestern Iberian Peninsula. Two previously studied boreholes (CM3 and CM5) were revisited and analyzed in the light of a foraminifera modern analog approach. Cluster analyses define four assemblages with different biocenotic, taphonomic, elevation and distance-to-sea settings, which serve as a baseline for paleoassemblages interpretation. Faunal changes along the sedimentary sequences, together with previous sedimentological and chronological data, redefine the different phases of environmental evolution in the Guadiana Estuary since ca. 13 kyr cal. BP, with special emphasis on the Holocene marine highstand. Estuarine flooding began synchronously in both locations (ca. 9 kyr cal. BP) but manifested differently in each sedimentary sequence. The most seaward borehole records a more evident and longer highstand (ca. 8.8–3.8 kyr cal. BP), characterized by the occurrence of subtidal environments and by the presence of open marine species ( Pararotalia cf. spinigera, planktic forms and a significant number of exotic/allochthonous tests), indicating warmer and more marine conditions than today. In the most landward borehole, the highstand is shorter (ca. 8–7.6 kyr cal. BP) and less intense, characterized by the presence of a diverse, mainly autochthonous, open estuary assemblage, dominated by Ammonia aberdoveyensis and Haynesina germanica. At 4.4 kyr cal. BP, during a long deceleration phase of regional sea-level rise, a short but well-defined pulse of marine influence is recorded in CM5, when open estuarine assemblages reappear and replace marsh agglutinated assemblages, suggesting a new submergence phase. This short event is not identified in the previous works carried out in the same area, thus further data are needed to understand whether it is consequent from a global, warming period or whether it resulted only from local and ephemeral forcing effects.

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Poignant, A., R. Mathieu, A. Levy, and B. Cahuzac. "Haynesina germanica (Ehrenberg), Elphidium excavatum (terquem) L.S. et Porosononion granosum (d'orbigny), espèces margino-littorales de Foraminifères d'aquitaine centrale (So France) au miocène moyen (langhien). Le problème d'elphidium lidoense cushman." Revue de Micropaléontologie 43, no. 3 (September 2000): 393–405. http://dx.doi.org/10.1016/s0035-1598(00)90200-9.

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Deldicq, Noémie, Florian Mermillod-Blondin, and Vincent M. P. Bouchet. "Sediment reworking of intertidal sediments by the benthic foraminifera Haynesina germanica : the importance of motion behaviour and densities." Proceedings of the Royal Society B: Biological Sciences 290, no. 1994 (March 8, 2023). http://dx.doi.org/10.1098/rspb.2023.0193.

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This study aimed to describe for the first time the vertical motion behaviour of the intertidal foraminifera Haynesina germanica and its contribution to bioturbation. Its infaunal behaviour leads to the creation of a one-end tube within the first centimetre of sediment. In addition, a vertical trail following behaviour was described for the first time in foraminifera, which may be linked to the sustainability of the biogenic sedimentary structures. As a consequence, H. germanica produces a vertical transport of both mud and fine sediment fractions similarly to the sediment reworking mode reported for gallery-diffusor benthic species. This finding allows us to refine the bioturbating mode of H. germanica , previously classified as surficial biodiffusor. Furthermore, sediment reworking intensity appeared to be dependent on the foraminiferal density. H. germanica would adapt its motion behaviour to deal with the intra-specific competition for food and space that may occur when density increases. Consequently, this behavioural modification would affect both the species and the individual contribution to sediment reworking processes. In fine , sediment reworking in H. germanica may further contribute to the bioirrigation of intertidal sediments, which has implications for oxygen availability in sediments and on aerobic microbial processes involved in carbon and nutrient cycling at the sediment–water interface.

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Cisneros-Lazaro, Deyanira, Arthur Adams, Jinming Guo, Sylvain Bernard, Lukas P. Baumgartner, Damien Daval, Alain Baronnet, et al. "Fast and pervasive diagenetic isotope exchange in foraminifera tests is species-dependent." Nature Communications 13, no. 1 (January 10, 2022). http://dx.doi.org/10.1038/s41467-021-27782-8.

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AbstractOxygen isotope compositions of fossil foraminifera tests are commonly used proxies for ocean paleotemperatures, with reconstructions spanning the last 112 million years. However, the isotopic composition of these calcitic tests can be substantially altered during diagenesis without discernible textural changes. Here, we investigate fluid-mediated isotopic exchange in pristine tests of three modern benthic foraminifera species (Ammonia sp., Haynesina germanica, and Amphistegina lessonii) following immersion into an 18O-enriched artificial seawater at 90 °C for hours to days. Reacted tests remain texturally pristine but their bulk oxygen isotope compositions reveal rapid and species-dependent isotopic exchange with the water. NanoSIMS imaging reveals the 3-dimensional intra-test distributions of 18O-enrichment that correlates with test ultra-structure and associated organic matter. Image analysis is used to quantify species level differences in test ultrastructure, which explains the observed species-dependent rates of isotopic exchange. Consequently, even tests considered texturally pristine for paleo-climatic reconstruction purposes may have experienced substantial isotopic exchange; critical paleo-temperature record re-examination is warranted.

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Raposo, Débora, Fabrizio Frontalini, Iara Clemente, Erminda da Conceição Guerreiro Couto, Fábio Veríssimo, and Lazaro Laut. "Benthic Foraminiferal Response to Trace Elements in a Tropical Mesotidal Brazilian Estuary." Estuaries and Coasts, June 23, 2022. http://dx.doi.org/10.1007/s12237-022-01095-5.

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AbstractLiving benthic foraminifera have been widely used as ecological indicators in coastal ecosystems. There is, however, a lack of studies on their response to trace element pollution in tropical estuarine systems. Here we analyze the living assemblages of benthic foraminifera, collected in 2016, in the Cachoeira River Estuary (CRE) in northeastern Brazil, to understand their response to natural and anthropogenic stressors, including trace element pollution. Some species were good bioindicators of specific environmental conditions, such as the agglutinant Paratrochammina clossi which preferred mangrove areas and anoxic conditions. In addition, the calcareous Ammonia tepida and Cribroelphidium excavatum, dominant within the whole system disregarding organic or trace element pollution, seem to resist even in the areas most polluted by trace elements. Interestingly, C. excavatum showed a particular positive relationship with trace element pollution (specifically by Cu and Pb), outnumbering the opportunistic A. tepida in the areas with higher pollution of these metals. However, for other species, it is still difficult to constrain to which parameters they respond (i.e., Haynesina germanica and Elphidium gunteri, which in the present study seem to respond to natural conditions, whereas in the literature they are regarded as indicators of trace element and organic pollution, respectively). Therefore, our findings shed light on the response of benthic foraminiferal species in a highly polluted and highly mixed tropical estuarine system and highlight the need to understand the complexity of these environments when applying foraminiferal biological indexes to avoid imprecise conclusions.

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Schmidt, Sarina, and Joachim Schönfeld. "Living and dead foraminiferal assemblage from the supratidal sand Japsand, North Frisian Wadden Sea: distributional patterns and controlling factors." Helgoland Marine Research 75, no. 1 (September 28, 2021). http://dx.doi.org/10.1186/s10152-021-00551-2.

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AbstractSupratidal sands are vitally important for coastal defence in the German Wadden Sea. They are less affected by human activities than other areas as they are located far off the mainland shore, touristical and commercial activities are generally prohibited. Therefore, supratidal sands are of high ecological interest. Nevertheless, the faunal inventory and distribution pattern of microorganisms on these sands were studied very little. The composition of living and dead foraminiferal assemblages was therefore investigated along a transect from the supratidal sand Japsand up to Hallig Hooge. Both assemblages were dominated by calcareous foraminifera of which Ammonia batava was the most abundant species. Elphidium selseyense and Elphidium williamsoni were also common in the living assemblage, but Elphidium williamsoni was comparably rare in the dead assemblage. The high proportions of Ammonia batava and Elphidium selseyense in the living assemblage arose from the reproduction season that differed between species. While Ammonia batava and Elphidium selseyense just finished their reproductive cycles, Elphidium williamsoni was just about to start. This was also confirmed by the size distribution patterns of the different species. The dead assemblage revealed 20 species that were not found in the living assemblage of which some were reworked from older sediments (e.g., Bucella frigida) and some were transported via tidal currents from other areas in the North Sea (e.g., Jadammina macrescens). The living foraminiferal faunas depicted close linkages between the open North Sea and the mainland. Key species revealing exchange between distant populations were Haynesina germanica, Ammonia batava and different Elphidium species. All these species share an opportunistic behaviour and are able to inhabit a variety of different environments; hence, they well may cope with changing environmental conditions. The benthic foraminiferal association from Japsand revealed that transport mechanisms via tides and currents play a major ecological role and strongly influence the faunal composition at this site.

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