RECENT PUBLICATIONS ON FORAMINIFERA 2012 (4)
FORAMINIFERAL REPOPULATION OF THE LATE EOCENE CHESAPEAKE BAY IMPACT CRATER
The Chickahominy Formation is the initial postimpact deposit in the 85km-diameter Chesapeake Bay impact crater, which is centered under the town of Cape Charles, Virginia, USA. The formation comprises dominantly microfossil-rich, silty, marine clay, which accumulated during the final ~1.6myr of late Eocene time. At cored sites, the Chickahominy Formation is 16.8-93.7m thick, and fills a series of small troughs and subbasins, which subdivide the larger Chickahominy basin. Nine coreholes drilled through the Chickahominy Formation (five inside the crater, two near the crater margin, and two ~3km outside the crater) record the stratigraphic and paleoecologic succession of 301 indigenous species of benthic foraminifera, as well as associated planktonic foraminifera and bolboformids. Two hundred twenty of these benthic species are described herein, and illustrated with scanning electron photomicrographs. ...... Absence of key planktonic foraminiferal and Bolboforma species in early Chickahominy sediments indicates that detrimental effects of the impact also disturbed the upper oceanic water column for at least 80-100kyr postimpact. ...... After an average of ~73kyr of stressed, rapidly fluctuating paleoenvironments, which were destabilized by after-effects of the impact, most of the cored Chickahominy subbasins maintained stable, nutrient-rich, low-oxygen bottom waters and interstitial microhabitats for the remaining ~1.3myr of late Eocene time. (ABSTRACT)
Poag, C.W., 2012. Foraminiferal repopulation of the Late Eocene Chesapeake Bay Impact Crater. Micropaleontology 58 (1-2), 1-206.
CENOZOIC ENVIRONMENTAL SHIFS AND FORAMINIFERAL EVOLUTION
The dense record of Cenozoic foraminifera simultaneously supplies a mosaic of biostratigraphy, a rich field for evolutionary studies and the vehicles for geochemical environmental proxies. Four groups are discussed: the larger foraminifera on the warm-water shelves and platforms, the planktonics, the deep-sea faunas and the southern-extratropical benthics. The environmental trajectory from greenhouse in the later Cretaceous and earlier Paleogene to icehouse in the Neogene is not smooth but punctuated, and there are two particularly critical intervals, later Eocene and early-middle Miocene. The foraminiferal record is not smooth but chunky at 107 years’ scale. There are several good examples of two powerful synchroneities, one being between the faunas of the different realms and the other between the fossil record and the physical-environmental record. (ABSTRACT)
McGowran, B., 2012. Cenozoic Environmental Shifts and Foraminiferal Evolution. In: Talent, J.A. (Ed.), Earth and Life: International Year of Planet Earth, 5, pp. 937-965.
RELATIONSHIP BETWEEN COILING DIRECTION AND PROLOCULUS SIZE IN MODERN PLANKTIC FORAMINIFERA
A total of 25 surface sediment samples, collected along a North-South transect (from 9.69° N to 55.01° S and from 80° E and 40° E) in the south western Indian Ocean, were used to study the coiling direction patterns in foraminifera planktonic species Neogloboquadrina pachyderma, Globigerinita glutinata and Globigerina bulloides. Comparison between the coiling direction and mean proloculus size (MPS) revealed that all these profiles along N-S transect were not in tandem and thus indicated non-existence of any relationship between the coiling direction and reproductive modes expressed in terms of mean proloculus size. (ABSTRACT)
Khare, N., Mazumder, A., Govil, P., 2012. Do changes in coiling directions in planktonic foraminifera correspond to dimorphic reproduction?. Oceanography 52 (3), 364-371.
RECONSTRUCTION OF INFLOW OF ATLANTIC WATER TO ISFJORDEN, SVALBARD
The distribution patterns of benthic foraminifera faunas, stable isotopes and ice rafted debris (IRD) have been studied in piston core JM98-845-PC from Isfjorden, western Svalbard to reconstruct changes in the flow of Atlantic Water during the Holocene interglacial. ......
Highlights ► Benthic foraminifera and stable isotopes have been studied from Isfjorden, Svalbard ► The stable isotopes were measured in two benthic species with different seasonality ► Seasonal contrasts were high in the early Holocene and low in mid-late Holocene ► Bottom water temperatures were highest in the early Holocene ► A cold maximum occurred 4000–2000 years BP in Isfjorden (ABSTRACT)
Rasmussen, T.L., Forwick, M., Mackensen, A., in press. Reconstruction of inflow of Atlantic Water to Isfjorden, Svalbard during the Holocene: Correlation to climate and seasonality. Marine Micropaleontology, doi:110.1016/j.marmicro.2012.06.008
EFFECT OF MUNICIPAL WASTEWATERS ON BOTTOM SEDIMENT GEOCHEMISTRY AND BENTHIC FORAMINIFERA
Al-Arbaeen and Al-Shabab inlets are two Red Sea coastal inlets lying on the mid-coast of Jeddah City, Saudi Arabia. Forty-four surface sediment samples were collected from these inlets and surrounding areas during June 2010. Water depths and the overlying environmental parameters (temperature, salinity, pH and dissolved oxygen) of these samples were measured. Sediment samples were analyzed for variables, such as loss on ignition (LOI, organic matter), CaCO3, heavy metals (Fe, Mn, Cu, Zn, Cd, Ni, Cr and Pb) and benthic foraminifera to assess any changes in the environment of the inlets and surrounding areas. Variables distribution patterns indicated that mud sediments dominated the inlets and enriched by LOI, heavy metals and Ammonia tepida–Quinqueloculina seminula assemblage, whereas coarse (sand–gravel) sediments dominated the substrates of surrounding areas and enriched by CaCO3 and Coscinospira hemprichii–Peneroplis planatus–Varidentella neostriatula assemblage with low values of LOI and heavy metals. ......
Abu-Zied, R.H., Basaham, A.S., El Sayed, M.A., 2012. Effect of municipal wastewaters on bottom sediment geochemistry and benthic foraminifera of two Red Sea coastal inlets, Jeddah, Saudi Arabia. Environmental Earth Sciences, doi:10.1007/s12665-012-1751-7 .
Guembelitria FROM THE K-Pg SUCCESSION OF THE LANGPAR FORMATION, INDIA
Guembelitria is an essential biotic component in the Late Cretaceous-Early Paleogene (K/Pg) marine successions to provide crucial information about the K/Pg boundary; however, it is not well studied in Indian subcontinent. Biostratigraphically well constrained K/Pg successions of Therriaghat and Mahadeo in the East Khasi Hills District, Meghalaya, India provided a scope to present a comprehensive account of the genus in the perspective of differences of opinion about its species. A total of six species including Guembelitria langparensis n. sp., are recognized and their stratigraphic distribution is recorded. A review of the taxonomic validity of the known species, an evaluation of the diverse concepts of Guembelitria cretacea Cushman, and semiquantitative analysis of the recovered species permitted their clustering into two morphogroups that had different ecology. ......
Mukhopadhyay, S.K., 2012. Guembelitria (foraminifera) in the upper cretaceous-lower paleocene succession of the Langpar Formation, India and its paleoenvironmental implication. Journal of the Geological Society of India 79 (6), 627-651.
BENTHIC FORAMINIFERAL COMMUNITY IN A NATURALLY CO2-RICH COASTAL HABITAT
It is expected that the calcification of foraminifera will be negatively affected by the ongoing acidification of the oceans. Compared to the open oceans, these organisms are subjected to much more adverse carbonate system conditions in coastal and estuarine environments such as the southwestern Baltic Sea, where benthic foraminifera are abundant. This study documents the seasonal changes of carbonate chemistry and the ensuing response of the foraminiferal community with bi-monthly resolution in Flensburg Fjord. ...... Our results revealed that there is no dynamic response of foraminiferal population density and diversity to elevated sediment pore water pCO2. Surprisingly, the fluctuations of sediment pore water undersaturation (Ωcalc) co-vary with the population densities of living Ammonia aomoriensis. Further, we observed that most of the tests of living calcifying specimens were intact. Only Ammonia aomorienis showed dissolution and recalcification structures on the tests, especially at undersaturated conditions. Therefore, the benthic community is subjected to constantly high pCO2 and tolerates elevated levels as long as sediment pore water remains supersaturated. ......
Haynert, K., Schönfeld, J., Polovodova-Asteman, I., Thomsen, J., 2012. The benthic foraminiferal community in a naturally CO2-rich coastal habitat in the southwestern Baltic Sea. Biogeosciences Discuss 9, 7783-7830.
INFLUENCE OF DIAGENESIS ON THE STABLE ISOTOPIC COMPOSITION OF BIOGENIC CARBONATES
In order to evaluate the influence of diagenetic and post-sampling processes on the stable oxygen and carbon isotope compositions of biogenic carbonates, we conducted a multiproxy study of organic-rich sediments from the eastern Pacific oxygen minimum zone. Core MD02-2520, which was retrieved from the Gulf of Tehuantepec (Mexico), has seasonal laminations and covers the last 40 kyr. Together with the presence of gypsum crystals and inorganic calcite aggregates, the occurrence of large excursions in the stable oxygen and carbon isotope records of both planktonic and benthic foraminifera (as large as +3‰ in δ18O and −5‰ in δ13C) point to significant secondary transformations. .....
- Large excursions in the foraminiferal isotope record
- Widespread inorganic calcite and gypsum precipitation during early diagenesis
- Gypsum formation probably related to sufide oxidation and disproportionation
Blanchet, C.L., Kasten, S., Vidal, L., Poulton, S.W., Ganeshram, R., Thouveny, N., 2012. Influence of diagenesis on the stable isotopic composition of biogenic carbonates from the Gulf of Tehuantepec oxygen minimum zone. Geochemistry Geophysics Geosystems 13, Q04003, 20 pp.
70 kD STRESS PROTEIN IN LIVING SHALLOW-WATER BENTHIC FORAMINIFERA
Hsp70 is a phylogenetically highly conserved protein family present in all eukaryotic organisms tested so far. Its synthesis is induced by proteotoxic stress. The detection of Hsp70 in foraminifera is presented here for the first time. We introduce a standard immunoblotting protocol modified for the detection of Hsp70 in shallow-water benthic foraminifera. Additionally, we showed a temperature-dependent expression pattern of Hsp70 in Ammonia tepida. (ABSTRACT)
Heinz, P., Marten, R.A., Linshy, V.N., Haap, T., Geslin, E., Köhler, H.R., 2012. 70 kD stress protein (Hsp70) analysis in living shallow-water benthic foraminifera. Marine Biology Research 8 (7), 677-681.
THE INTEGRATED BIOSTRATIGRAPHY OF THE MIOCENE SAN BARTOLOMEO FLYSCH, SOUTHERN APENNINE CHAIN
The present paper deals with the stratigraphic and biostratigraphic study of the middle-late Miocene thrust-top basin deposits of the San Bartolomeo Flysch, exposed north of Matese mountains and analysed during the geological survey of the sheet N° 405 Campobasso of the new Geological Map of Italy, 1:50.000 scale. The integrated study of calcareous nannofossils and planktonic foraminifera, based on the semi-quantitative distribution range of index species, revealed the presence of age-diagnostic assemblages which are comparable with those of different middle-late Miocene deep-marine sedimentary settings of the Mediterranean Basin. ...... This study documents the applicability of the recent Mediterranean middle –late Miocene biozonations for the biostratigraphic study of siliciclastic synorogenic sediments, and challenges the most recent studies that dated the San Bartolomeo Flysch to the late Tortonian- early Messinian. (ABSTRACT)
Cascella, A., Lirer, F., Cesarano, M., Casciello, E., Pappone, G., 2012. Integrated stratigraphy of middle-late Miocene synorogenic deposits of the eastern southern Apennine Chain: The San Bartolomeo Flysch. Rivista Italiana di Paleontologia e Stratigrafia 118 (2).
SHOALING OF THE WESTERN EQUATORIAL PACIFIC THERMOCLINE DURING THE LGM
Glacial–interglacial scale climate variability in the tropical Pacific is often discussed with reference to modern El Niño-Southern Oscillation (ENSO). However, proxy records show diverse results and result in inconsistent interpretations. To investigate changes in the thermocline depth of the western Pacific warm pool (WPWP), which is strongly related to the strength of the Walker circulation, this study conducted δ18O and Mg/Ca analyses of multispecies planktonic foraminifera for the last 25,000 years. Habitat depths and calcification temperatures of seven foraminiferal species were estimated by comparing measured δ18O values with the predicted values by assuming isotopic equilibrium. Reconstructed Mg/Ca-based temperatures, calculated with a newly calibrated multispecies equation, showed ~ 1–2 °C larger cooling at the thermocline depth than that at the surface during the last glacial maximum (LGM), suggesting shoaling of the thermocline. Furthermore, fresher surface water in the WPWP, which is attributed to the suppressed evaporation by low sea surface temperature, suggests the weakened deep atmospheric convection. These results suggest that the Walker circulation during the LGM was weaker than that during the late Holocene.
Sagawa, T., Yokoyama, Y., Ikehara, M., Kuwae, M., in press. Shoaling of the western equatorial Pacific thermocline during the last glacial maximum inferred from multispecies temperature reconstruction of planktonic foraminifera. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.06.002
THE INFLUENCE OF PRODUCTIVITY ON ABYSSAL FORAMINIFERAL BIODIVERSITY
The quantity and quality of organic matter reaching the deep-sea floor is believed to exert a strong control on benthic foraminiferal assemblages, including the diversity and density of populations and the distribution patterns of species. In addition, some species seem to be associated with strong seasonality in primary productivity. We test relationships between diversity and mean annual productivity based on carefully selected datasets (>63-μm sieve fraction including soft-shelled taxa) from the NE Atlantic, Weddell Sea, and Equatorial and North Pacific. We used (1) ‘live’ (Rose Bengal stained) foraminiferal density, (2) mean annual surface productivity and (3) estimated organic carbon flux to the seafloor as proxies for food supply to the benthos. ...... We also considered published datasets from the Arctic (Wollenburg and Mackensen Mar Micropaleontol 34: 153–185, 1998) and North Atlantic (Corliss et al. Deep-Sea Res 56: 835–841, 2009) Oceans. ...... Additional analyses of ‘seasonal’ and ‘non-seasonal’ N Atlantic sites with a comparable range of estimated flux values (2–4 g C m−2 year−1) revealed that diversity increased with increasing flux and density in both cases, with significantly lower diversity at the seasonal compared to the non-seasonal sites. The contradictions between our data (−ve relationship between food availability and diversity) and those of Wollenburg and Corliss (+ve relationship) are difficult to explain and underline the need for further studies employing consistent methods to analyse ‘entire live’ assemblages across productivity gradients. (ABSTRACT)
Gooday, A.J., Bett, B.J., Jones, D.O.B., Kitazato, H., in press. The influence of productivity on abyssal foraminiferal biodiversity. Marine Biodiversity, doi:10.1007/s12526-012-0121-8
THE FOBIMO (FOraminiferal BIo-MOnitoring) PROTOCOL
The European Community Marine Strategy Framework Directive (MSFD) was established to provide guidelines for monitoring the quality of marine ecosystems. Monitoring the status of marine environments is traditionally based on macrofauna surveys, for which standardised methods have been established. Benthic foraminifera are also good indicators of environmental status because of their fast turnover rates, high degree of specialisation, and the preservation of dead assemblages in the fossil record. In spite of the growing interest in foraminiferal bio-monitoring during the last decades, no standardised methodology has been proposed until today. The aim of the FOraminiferal BIo-MOnitoring (FOBIMO) expert workshop, held in June 2011 at Fribourg, Switzerland, which assembled 37 scientists from 24 research groups and 13 countries, was to develop a suite of standard methods. This paper presents the main outcome of the workshop, a list of motivated recommendations with respect to sampling devices, sample storage, treatment, faunal analysis and documentation. ...... We are convinced that the application of this protocol by a large number of scientists is a necessary first step to a general acceptance of benthic foraminifera as a reliable tool in bio-monitoring studies. (ABSTRACT)
Schönfeld, J., Alve, E., Geslin, E., Jorissen, F., Korsun, S., Spezzaferri, S., Members of the FOBIMO group, in press. The FOBIMO (FOraminiferal BIo-MOnitoring) initiative - towards a standardised protocol for soft-bottom benthic foraminiferal monitoring studies. Marine Micropaleontology, doi:10.1016/j.marmicro.2012.06.001
HUMAN-MEDIATED NUTRIFICATION OVER THE SCALE OF DECADES
Community assemblages of live and dead benthic foraminifera from Kiritimati (Christmas) Island, Kiribati, were used to investigate changes in nutrification before and after human occupation. Benthic foraminiferal assemblages have previously been shown to have strong empirical relationships with water quality: mixotrophic, symbiont-bearing foraminifera dominate in clear, nutrient-poor waters, while heterotrophic and/or opportunistic foraminifera are more prevalent in polluted or nutrified waters. After human occupation, the proportion of mixotrophic taxa decreased significantly at all sites on Kiritimati with the largest decreases observed at sites with the highest fishing pressure. These changes in the benthic foraminiferal assemblage indicate that nutrification has occurred on Kiritimati over the scale of decades, possibly due to changes in trophic structure and nutrient cycling caused by fishing.
Carilli, J., Walsh, S., 2012. Benthic foraminiferal assemblages from Kiritimati (Christmas) Island indicate human-mediated nutrification has occurred over the scale of decades. Marine Ecology Progress Series 456, 87-99.
SIZE-FREQUENCY DISTRIBUTIONS ALONG A LATITUDINAL GRADIENT IN MID PERMIAN FUSULINOIDEANS
Geographic gradients in body size within and among living species are commonly used to identify controls on the long- term evolution of organism size. However, the persistence of these gradients over evolutionary time remains largely unknown because ancient biogeographic variation in organism size is poorly documented. Middle Permian fusulinoidean foraminifera are ideal for investigating the temporal persistence of geographic gradients in organism size because they were diverse and abundant along a broad range of paleo-latitudes during this interval (,275–260 million years ago). In this study, we determined the sizes of Middle Permian fusulinoidean fossils from three different paleo-latitudinal zones in order to examine the relationship between the size of foraminifers and regional environment. ...... Consequently, our findings highlight the fact that spatial gradients in organism size are not always controlled by the same factors that govern temporal trends within the same clade.
Zhang, Y., Payne, J.L., 2012. Size-Frequency Distributions along a Latitudinal Gradient in Middle Permian Fusulinoideans. PLoS ONE 7 (6): e38603. doi:10.1371/journal.pone.0038603
DEEP-SEA FORAMINIFERA FROM THE BAY OF BENGAL
The present study encompasses a detailed investigation of downcore Holocene foraminifera and their assemblages to comprehend the ecology of the Bay of Bengal and compare it with that of the South China and Sulu Seas, at the same depth for all the three water bodies. Based on temperature and dissolved oxygen profiles, benthic foraminiferal abundance, and species diversity values, it is inferred that the Bay of Bengal is much better ventilated than either the South China or the Sulu Sea. The planktic/benthic (P/B) ratios are extremely low when compared with those reported elsewhere in the world. The absolute dominance of benthic foraminiferal species over their planktic counterparts is attributed to the effect of fragmentation and dissolution of the latter, as they are relatively more susceptible to this process. The very low P/B values are also indicative of water depth below the lysocline in this part of the Bay of Bengal.
Rajeshwara Rao, N., Kamatchi, P., Ramesh, S., 2012. Deep-sea foraminifera in a short core from the Bay of Bengal: ecological comparisons with the South China and Sulu Seas. Arabian Journal of Geosciences, doi:10.1007/s12517-012-0601-y
MARINE CLIMATES AND LOCAL TECTONIC EVENTS IN SW JAPAN AT THE PLIO-PLEISTOCENE BOUNDARY
This study reconstructs the temporal changes in water temperature and depth on the Pacific coast of Southwest Japan from the latest Pliocene to the earliest Pleistocene (ca. 2.6 Ma) on the basis of the modern analogue technique (MAT) of fossil ostracodes and factor analysis of fossil planktonic foraminifera from the Takanabe Formation. Around the Plio-Pleistocene boundary, the MAT results reveal that the mean annual, warmest month, and coldest month temperatures of bottom water were estimated at ca. 6–17, 6–17, and 6–16 °C, respectively. The bottom water temperature before 2.6 Ma was similar to modern temperatures off the study site. Since then, the temperature dropped several degrees. Moreover, the result of the analysis of fossil planktonic foraminifera suggests that the study site clearly changed from a marine climate under the influence of the axial part of the Kuroshio Current to that of transitional water at around 2.6 Ma. ......
Highlights ► We quantitatively examined paleoenvironments of Plio–Pleistocene in SW Japan. ► Paleo-water temperature and depth were estimated at ca. 6–17 °C and ca. 100–350 m. ► At least 51 planktonic foraminiferal taxa were obtained. ► A distinct cooling occurred at Plio–Pleistocene boundary on Pacific of SW Japan. ► A tectonic movement related to rotation of southern Kyushu occurred at ca 2.6 Ma.
Iwatani, H., Irizuki, T., Hayashi, H., in press. Global cooling in marine climates and local tectonic events in Southwest Japan at the Plio–Pleistocene boundary. Palaeogeography, Palaeoclimatology, Palaeoecology, doi:10.1016/j.palaeo.2012.05.025
ACIDIFICATION OF EXTRACELLULAR MICROENVIRONMENTS DURING CALCIFICATION
Calcareous foraminifera are well known for their CaCO3 shells. Yet, CaCO3 precipitation acidifies the calcifying fluid. Calcification without pH regulation would therefore rapidly create a negative feedback for CaCO3 precipitation. In unicellular organisms, like foraminifera, an effective mechanism to counteract this acidification could be the externalization of H+ from the site of calcification. In this study we show that a benthic symbiont-free foraminifer Ammonia sp. actively decreases pH within its extracellular microenvironment only while precipitating calcite. ......
Highlights ► Microsensor measurements around a benthic foraminifer (Ammonia sp.). ► pH and Ca2+ microenvironmental dynamics at different life stages. ► pH decreases on the test surface while precipitating calcite. ► H+ expulsion during calcification as a mean to maintain pH homeostasis. (ABSTRACT)
Glas, M.S., Langer, G., Keul, N., 2012. Calcification acidifies the microenvironment of a benthic foraminifer (Ammonia sp.). Journal of Experimental Marine Biology and Ecology 424-425, 53-58.
QUANTIFICATION OF PROTEIN BIOMASS OF INDIVIDUAL FORAMINIFERA
The ecological role of foraminifers has been largely unknown partly owing to difficulties in determining their individual biomass, although foraminifers are abundant in surface marine sediments. The present study provides a reliable and inexpensive method for the quantification of the protein content of hard-shelled foraminifers as a measure of biomass while preserving the tests for later analyses (e.g., morphometry, stable isotopes) using nano-spectrophotometry. The protein biomass, size, and shell weight of Ammonia tepida are significantly correlated (n = 102, p < 0.001, R2 = 0.5739, and n = 181, p < 0.001, R2 = 0.8288, respectively). Variability in relation between test size and weight, and cell biomass may result from natural variability in horizontal and vertical microenvironments encompassing metabolic state, as well as variability in test morphometry and calcite mass (i.e., test weight). In turn, knowing the size- and species-specific biomass of foraminifers adds valuable information on the trophic and ecologic conditions of modern and ancient marine environments, in particular on the reconstruction of the regional paleoproductivity and flux of organic matter.
Movellan, A., Schiebel, R., Zubkov, M.V., Smyth, A., Howa, H., 2012. Quantification of protein biomass of individual foraminifers using nano-spectrophotometry. Biogeosciences Discuss 9, 6651-6681.
BIO- AND MAGNETOSTRATIGRAPHY OF BADENIAN SEQUENCES FROM WESTERN AND NORTHERN HUNGARY
Lithological, magnetostratigraphic and paleontological (nannoplankton, foraminifers, molluscs) studies were carried out on the Badenian successions of boreholes Sopron-89, Nagylózs-1 and Sata-75 in Hungary. The correlations with the ATNTS2004 scale show that the Badenian sedimentation began during Chron C5Br thus the earliest Badenian deposits are missing in the sections. The first occurrence of Orbulina suturalis Brönnimann has been observed in Subchron C5Bn.1r, at 14.9 Ma. Although it is older than the interpolated age of 14.74 Ma in Chron C5ADr in the ATNTS2004, it is consistent with the age of 15.1 Ma obtained from recent calibration of planktonic foraminiferal bioevents. The base of the Bulimina-Bolivina Zone has been determined at 13.7 Ma in Chron C5ABr, and the Badenian/Sarmatian boundary is recorded within Chron C5AAn, at 13.15 Ma. (ABSTRACT)
Selmeczi, I., Lantos, M., Bohn-Havas, M., Nagymarosy, A., Szego, E., 2012. Correlation of bio- and magnetostratigraphy of Badenian sequences from western and northern Hungary. Geologica Carpathica 63 (3), 219-232.
ECOLOGICAL PARTITIONING AND DIVERSITY IN TROPICAL PLANKTONIC FORAMINIFERA
We uncovered extensive genetic diversity within the Arabian Sea planktonic foraminifera, identifying 13 morphospecies, represented by 20 distinct SSU rRNA genetic types. Several morphospecies/genetic types displayed non-random biogeographical distributions, partitioning between the northern and southern water masses, giving a strong indication of independent ecological adaptations.
We propose sea-surface primary productivity as the main factor driving the geographical segregation of Arabian Sea planktonic foraminifera, during the SW monsoon, with variations in symbiotic associations possibly playing a role in the specific ecological adaptations observed. Our findings suggest that ecological partitioning could be contributing to the high levels of 'cryptic' genetic diversity observed within the planktonic foraminifera, and support the view that ecological processes may play a key role in the diversification of marine pelagic organisms. (ABSTRACT)
Seears, H.A., Darling, K.F., Wade, C.M., 2012. Ecological partitioning and diversity in tropical planktonic foraminifera. BMC Evolutionary Biology 12 (1), 54.
CALCIFICATION AND PHOTOBIOLOGY IN SYMBIONT-BEARING BENTHIC FORAMINIFERA IN A HIGH CO2 ENVIRONMENT
The present study investigates impacts of ocean acidification on calcification rates and light responses of large benthic foraminifera (LBF). Studies were conducted on diatom-bearing Amphistegina radiata and Heterostegina depressa and dinoflagellate-bearing Marginopora vertebralis in controls and manipulated seawater pCO2 conditions (467–1925 μatm pCO2).
Highlights ► The response to pCO2 increase was investigated on three benthic foraminifera. ► M. vertebralis shows increased calcification after 41 days in elevated CO2 dosing. ► Increased pCO2 showed no effect on photobiology of the foraminifera investigated. ► Previous field studies indicate long-term impacts of high CO2 conditions. ► The study highlights that laboratory experiments can differ from field observation. (ABSTRACT)
Vogel, N., Uthicke, S., 2012. Calcification and photobiology in symbiont-bearing benthic foraminifera and responses to a high CO2 environment. Journal of Experimental Marine Biology and Ecology 424-425, 15-24.
ANTARCTIC GLACIATION RECORDED IN EARLY MIOCENE NEW ZEALAND FORAMINIFERA
New Zealand sedimentary sequences are important repositories of southern temperate paleoenvironmental data, as may be interpreted from biogenic chemical signals preserved in marine microfossils. Calibration curves for Mg/Ca ratios versus water temperatures were established using modern benthic foraminifera, Notorotalia and Cibicides.
Highlights ► We measured δ18O and Mg/Ca from Early Miocene benthic foraminifera (17.7 Ma) ► Bottom water paleotemperature was approximately 14 °C at paleolatitude 43.3°S ► Paleo-seawater δ18O averaged -0.4 ± 0.4‰ (VSMOW) throughout the studied sequence ► δ18O and Mg/Ca in New Zealand strata reveal changes in Antarctic ice volume (ABSTRACT)
Fukuda, K., Thomas, D.B., Frew, R.D., Fordyce, R.E., in press. Antarctic glaciation recorded in Early Miocene New Zealand foraminifera. Marine Micropaleontology, doi:10.1016/j.marmicro.2012.05.002
TAPHONOMIC PROCESSES AND PALEOENVIRONMENTAL APPLICATIONS
Highlights ► Dead benthic foraminifera were studied at 18 stations in the Whittard Canyon area. ► Dead fauna were compared with live communities in canyon axes and in open slopes. ► In canyon axes, the use of dead fauna to reconstruct paleoenvironmental is precluded. ► Dead fauna in the canyon axes can give clues about the downslope sedimentary dynamics. ► On open slopes, dead assemblages appear to reflect local conditions fairly accurately. (ABSTRACT)
Duros, P., Fontanier, C., de Stigter, H.C., Cesbron, F., Metzger, E., Jorissen, F.J., in press. Live and dead benthic foraminiferal faunas from Whittard Canyon (NE Atlantic): Focus on taphonomic processes and paleo-environmental applications. Marine Micropaleontology, doi:10.1016/j.marmicro.2012.05.004
A TAXONOMIC GUIDE TO MODERN BENTHIC SHELF FORAMINIFERA OF THE W MEDITERRANEAN SEA
A total of 288 modern benthic carbonate shelf foraminifera in three areas of the Western Mediterranean Sea (Alboran Platform, Oran Bight and the southwest shelf of Mallorca) have been studied and are systematically listed. This systematic description provides a list of synonyms, short remarks about morphological features of the taxa and some annotations about taxa with problematic generic status. Most of the taxa are illustrated by SEM photographs.
Milker, Y., Schmiedl, G., 2012. A taxonomic guide to modern benthic shelf foraminifera of the western Mediterranean Sea. Palaeontologia Electronica 15 (2); 16A, 134p
EFFECTS OF OCEAN ACIDIFICATION ON PRODUCTIVITY AND CALCIFICATION IN Marginopora vertebralis
Changes in the seawater carbonate chemistry (ocean acidification) from increasing atmospheric carbon dioxide (CO2) concentrations negatively affect many marine calcifying organisms, but may benefit primary producers under dissolved inorganic carbon (DIC) limitation. To improve predictions of the ecological effects of ocean acidification, the net gains and losses between the processes of photosynthesis and calcification need to be studied jointly on physiological and population levels. We studied productivity, respiration, and abundances of the symbiont-bearing foraminifer species Marginopora vertebralis on natural CO2 seeps in Papua New Guinea and conducted additional studies on production and calcification on the Great Barrier Reef (GBR) using artificially enhanced pCO2. ...... The study showed that endosymbiotic algae in foraminifera benefit from increased DIC availability and may be naturally carbon limited. The observed reduction in calcification may have been caused either by increased energy demands for proton pumping (measured as elevated rates of respiration) or by stronger competition for DIC from the more productive symbionts. The net outcome of these two competing processes is that M. vertebralis cannot maintain populations under pCO2 exceeding 700 μatm, thus are likely to be extinct in the next century.
Uthicke, S., Fabricius, K.E., in press. Productivity gains do not compensate for reduced calcification under near-future ocean acidification in the photosynthetic benthic foraminifer species Marginopora vertebralis. Global Change Biology, doi: 10.1111/j.1365-2486.2012.02715.x
RECENT MACROIDS ON THE KIKAI-JIMA SHELF, CENTRAL RYUKYU ISLANDS, JAPAN
Sandy and gravelly carbonate sediments found off Kikai-jima, southern Japan, a coral reef-related island shelf, represent the northernmost sub-tropical, carbonate deposits in the Central Ryukyu Islands (Ryukyus). On the Kikai-jima shelf, at water depths of 61 to 105 m, these sediments are characterized by macroid pavements. Since the abundance of very small and of exceptionally large macroids may indicate specific hydrodynamic controls regarding constraints on growth and taphonomy, the detailed analysis of recent and fossil macroid pavements is meaningful ecologically and environmentally. Macroids, ranging in size from ca 25 to 130 mm in diameter, are spheroidal and sub-spheroidal in shape and consist mainly of the encrusting foraminifer Acervulina inhaerens and subordinate thin encrusting and lumpy coralline algae. ......
Bassi, D, Iryu, Y., Humblet, M., Matsuda, H., Machiyama, H., Sasaki, K., Matsuda, S., Arai, K., Inoue, T., in press. Recent macroids on the Kikai-jima shelf, Central Ryukyu Islands, Japan. Sedimentology, doi:10.1111/j.1365-3091.2012.01333.x
LATEST CAMPANIAN-MAASTRICHTIAN PALAEOENVIRONMENTAL CHANGES IN AN EPICONTINENTAL SEA
The Maastrichtian was a time of a high variability in the climate/ocean system. Most studies on Maastrichtian palaeoenvironment fluxes have been based on evidence from the open ocean realm or from outcrops in the Tethyan realm. We have investigated epicontinental carbonate-rich sediments of Maastrichtian age of the Lublin-Lviv Syncline (SE Poland and western Ukraine). Our study is focused on the population changes of planktonic foraminifers from 21 Maastrichtian outcrop successions and one borehole section. Quantitative and qualitative studies of planktonic foraminifers show long-term foraminiferal changes that make it possible to reconstruct climatic changes and a sea-level curve for the latest Campanian and Maastrichtian from the high-latitude epicontinental sea. A significant regression is inferred for the latest Campanian and earliest Maastrichtian. The highest sea level is noted in the earliest Late Maastrichtian. It coincides with a migration of the benthic and planktonic foraminiferal fauna that was probably triggered by a cooling episode. The cooler episodes correlated with a eustatic sea-level highstand during that time, suggesting that sea level was the most likely mechanism causing a change of global circulation; this temperature drop could be the cause of the mid-Maastrichtian event.
Dubicka, Z., Peryt, D., in press. Latest Campanian and Maastrichtian palaeoenvironmental changes: Implications from an epicontinental sea (SE Poland and western Ukraine). Cretceous Research, 10.1016/j.cretres.2012.04.009
BIOSTRATIGRAPHY, ISOTOPE STRATIGRAPHY, CYCLOSTRATIGRAPHY AND ASTRONOMICALLY CALIBRATED DURATION OF Radotruncana calcata ZONE
A section from the southern (Austro-Alpine Northern Calcareous Alps) margin of the Penninic Ocean in the NW Tethys realm of Late Campanian age is investigated stratigraphically. Plankton foraminifer and nannofossil biostratigraphy designate the presence of the Globotruncana ventricosa Zone and the Radotruncana (Globotruncanita) calcarata Zone, and standard nannofossil zones CC21–UC15cTP and CC22ab–UC15deTP. The combination of carbon isotope stratigraphy, strontium isotopes, and cyclostratigraphy allows a detailed chronostratigraphic correlation. Periodicity was obtained by power spectral analysis, sinusoidal regression, and Morlet wavelets. The duration of the calcarata Total Range Zone is calculated by orbital cyclicity expressed in thickness data of limestone–marl rhythmites and stable carbon isotope data. Precessional, obliquity, and short and long eccentricity cycles are identified and give an extent of c. 806 kyr for the zone. Mean sediment accumulation rates are as low as 1.99 cm/kyr and correspond well to sediment accumulation rates in similar settings. We further discuss chronostratigraphic implications of our data.
Wagreich, M., Hohenegger, J., Neuhuber, S., in press. Nannofossil biostratigraphy, strontium and carbon isotope stratigraphy, cyclostratigraphy and an astronomically calibrated duration of the Late Campanian Radotruncana calcarata Zone. Cretceous Research, doi:10.1016/j.cretres.2012.04.006
INCORPORATION OF Mg & Sr and ∂18O & ∂13C FRACTIONATION IN CULTURED Ammonia tepida
The shallow water benthic foraminiferal species Ammonia tepida was cultured in controlled temperature conditions (20 °C) at three different salinities (29.8, 32.2, and 35.5). The calcite shells of single individuals of different sizes that calcified entirely in controlled experimental conditions were analysed for their magnesium and strontium concentrations (LA-ICP-MS) as well as for their oxygen and carbon isotopic composition (pooled individuals). The approach used in this study allows us to investigate the effect of seawater salinity, inter-test variability and test size on the studied parameters. ......
Highlights ► Sr/Ca ratios decrease with Ammonia tepida size increase. ► Mg/Ca ratios show high inter-shell variability. ► There is no relation between Mg/Ca and Sr/Ca ratios to salinity (29.8–35.5 range). ► Oxygen isotopes are 0.3–0.45‰ heavier than predicted equilibrium values.
Diz, P., Barras, C., Geslin, E., Reichart, G.J., Metzger, E., Jorissen, F., Bijma, J., 2012. Incorporation of Mg and Sr and oxygen and carbon stable isotope fractionation in cultured Ammonia tepida. Marine Micropaleontology 92-93, 16-28.